geiger wip

Makefile

@@ -10,7 +10,20 @@ PROG_TYPE = arduino
 # Build the final AVRDUDE arguments
 PROG_ARGS = -c $(PROG_TYPE) -p $(MCU) -b $(PROG_BAUD) -P $(PROG_DEV)
 
-INCFLAGS += -Isrc -Ilib/libssd1306/src
+INCFLAGS += -Isrc -Ilib/libssd1306/src -Ilib/porklib
+
+LIB_SOURCES =
+#LIB_SOURCES += lib/porklib/uart.c
+#LIB_SOURCES += lib/porklib/uart.c
+LIB_SOURCES += lib/porklib/iopins.c
+#LIB_SOURCES += lib/porklib/stream.c
+LIB_SOURCES += lib/porklib/adc.c
+#LIB_SOURCES += lib/porklib/dht11.c
+#LIB_SOURCES += lib/porklib/sonar.c
+#LIB_SOURCES += lib/porklib/onewire.c
+#LIB_SOURCES += lib/porklib/spi.c
+#LIB_SOURCES += lib/porklib/sd.c
+#LIB_SOURCES += lib/porklib/fat16.c
 
 CFLAGS = -std=gnu99 -mmcu=$(MCU) -DF_CPU=$(F_CPU)UL
 CFLAGS += -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
@@ -40,7 +53,7 @@ OBJDUMP = avr-objdump
 AVRSIZE = avr-size
 AVRDUDE = avrdude
 
-SOURCES=$(wildcard $(SRC_DIR)/*.c)
+SOURCES=$(wildcard $(SRC_DIR)/*.c) $(LIB_SOURCES)
 OBJECTS=$(SOURCES:$(SRC_DIR)/%.c=$(BUILD_DIR)/%.o)
 DEPENDS=$(BUILD_DIR)/.depends
 
@@ -62,7 +75,11 @@ eeprom: $(TARGET).eeprom
 size: $(TARGET).elf
 	$(AVRSIZE) -C --mcu=$(MCU) $<
 
-$(TARGET).elf: $(OBJECTS) | $(BUILD_DIR)
+# Build the display library
+lib/libssd1306/bld/libssd1306.a:
+	$(MAKE) -C lib/libssd1306/ -f Makefile.avr MCU=atmega328p
+
+$(TARGET).elf: $(OBJECTS) lib/libssd1306/bld/libssd1306.a | $(BUILD_DIR)
 	$(LD) $(CFLAGS) $(LFLAGS) -o $@ $^ lib/libssd1306/bld/libssd1306.a
 
 %.hex: %.elf

lib/porklib/adc.c

@@ -0,0 +1,67 @@
+#include <avr/io.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "calc.h"
+#include "adc.h"
+
+/** Initialize the ADC */
+void adc_init()
+{
+	ADCSRA |= _BV(ADPS2) | _BV(ADPS1) | _BV(ADPS0);  // 128 prescaler -> 125 kHz
+//	ADCSRA |= _BV(ADPS2) | _BV(ADPS0);  // 32 prescaler -> 500 kHz, good for 8-bit measurement
+
+	ADMUX  |= _BV(REFS0) | _BV(REFS1);  // Voltage reference = internal 1.1V
+
+	sbi(ADCSRA, ADEN);  // Enable ADC
+}
+
+
+/** Disable AD */
+void adc_disable()
+{
+	cbi(ADCSRA, ADEN);
+}
+
+
+/** Sample analog pin with 8-bit precision */
+uint8_t adc_read_byte(uint8_t channel)
+{
+	set_low_nibble(ADMUX, channel);  // Select channel to sample
+	sbi(ADMUX, ADLAR);  // Align result to left
+	sbi(ADCSRA, ADSC);  // Start conversion
+
+	while (bit_is_high(ADCSRA, ADSC)); // Wait for it...
+
+	return ADCH;  // The upper 8 bits of ADC result
+}
+
+
+/** Sample analog pin with 10-bit precision */
+uint16_t adc_read_word(uint8_t channel)
+{
+	set_low_nibble(ADMUX, channel);  // Select channel to sample
+	cbi(ADMUX, ADLAR);  // Align result to right
+	sbi(ADCSRA, ADSC);  // Start conversion
+
+	while (get_bit(ADCSRA, ADSC)); // Wait for it...
+
+	return ADCW;  // The whole ADC word (10 bits)
+}
+
+/** Sample analog pin with 10-bit precision */
+void adc_async_start_measure_word(uint8_t channel)
+{
+	set_low_nibble(ADMUX, channel);  // Select channel to sample
+	cbi(ADMUX, ADLAR);  // Align result to right
+	sbi(ADCSRA, ADSC);  // Start conversion
+}
+
+bool adc_async_ready()
+{
+    return 0 == get_bit(ADCSRA, ADSC);
+}
+
+uint16_t adc_async_get_result_word() {
+    return ADCW;  // The whole ADC word (10 bits)
+}

lib/porklib/adc.h

@@ -0,0 +1,26 @@
+#pragma once
+
+//
+// Utilities for build-in A/D converter
+//
+
+#include <avr/io.h>
+#include <stdint.h>
+
+/** Initialize the ADC */
+void adc_init();
+
+/** Disable AD (for power saving?) */
+void adc_disable();
+
+/** Sample analog pin with 8-bit precision */
+uint8_t adc_read_byte(uint8_t channel);
+
+/** Sample analog pin with 10-bit precision */
+uint16_t adc_read_word(uint8_t channel);
+
+void adc_async_start_measure_word(uint8_t channel);
+
+bool adc_async_ready();
+
+uint16_t adc_async_get_result_word();

lib/porklib/blockdev.h

@@ -0,0 +1,66 @@
+#pragma once
+
+//
+// Block device interface, somewhat akin to stream.h
+// Used for filesystem implementations.
+//
+
+#include <stdint.h>
+
+/** Abstract block device interface
+ *
+ * Populate an instance of this with pointers to your I/O functions.
+ */
+typedef struct
+{
+	/** Sequential read at cursor
+	 * @param dest destination memory structure
+	 * @param len  number of bytes to load and store in {dest}
+	 */
+	void (*load)(void* dest, const uint16_t len);
+
+
+	/** Sequential write at cursor
+	 * @param src source memory structure
+	 * @param len number of bytes to write
+	 */
+	void (*store)(const void* src, const uint16_t len);
+
+
+	/** Write one byte at cursor
+	 * @param b byte to write
+	 */
+	void (*write)(const uint8_t b);
+
+
+	/** Read one byte at cursor
+	 * @return the read byte
+	 */
+	uint8_t (*read)(void);
+
+
+	/** Absolute seek - set cursor
+	 * @param addr new cursor address
+	 */
+	void (*seek)(const uint32_t addr);
+
+
+	/** Relative seek - move cursor
+	 * @param offset cursor address change
+	 */
+	void (*rseek)(const int16_t offset);
+
+
+
+	/** Flush the data buffer if it's dirty.
+	 *
+	 * Should be called after each sequence of writes,
+	 * to avoid data loss.
+	 *
+	 * Tmplementations that do not need this should provide
+	 * a no-op function.
+	 */
+	void (*flush)(void);
+
+} BLOCKDEV;
+

lib/porklib/calc.h

@@ -0,0 +1,89 @@
+#pragma once
+
+//
+// Bit and byte manipulation utilities
+//
+
+#include <stdint.h>
+
+
+// --- Increment in range ---
+// when overflown, wraps within range. Lower bound < upper bound.
+// ..., upper bound excluded
+#define inc_wrap(var, min, max)  { if ((var) >= (max - 1)) { (var) = (min); } else { (var)++; } }
+// ..., upper bound included
+#define inc_wrapi(var, min, max) inc_wrap((var), (min), (max) + 1)
+
+
+// --- Decrement in range ---
+// when underflown, wraps within range. Lower bound < upper bound.
+// ..., upper bound excluded
+#define dec_wrap(var, min, max)  { if ((var) <= (min)) { (var) = (max) - 1; } else { (var)--; } }
+// ..., upper bound included
+#define dec_wrapi(var, min, max) dec_wrap((var), (min), (max) + 1)
+
+
+// --- Bit manipulation --
+
+// Set bit
+#define sbi(reg, bit) { (reg) |=  (1 << (uint8_t)(bit)); }
+
+// Clear bit
+#define cbi(reg, bit) { (reg) &= ~(1 << (uint8_t)(bit)); }
+
+// Get n-th bit
+#define get_bit(reg, bit) (((reg) >> (uint8_t)(bit)) & 0x1)
+
+// Test n-th bit (Can't use bit_is_set, as it's redefined in sfr_def.h)
+#define bit_is_high(reg, bit) get_bit(reg, bit)
+#define bit_is_low(reg, bit)  (!get_bit(reg, bit))
+
+// Write value to n-th bit
+#define set_bit(reg, bit, value) { (reg) = ((reg) & ~(1 << (uint8_t)(bit))) | (((uint8_t)(value) & 0x1) << (uint8_t)(bit)); }
+
+// Invert n-th bit
+#define toggle_bit(reg, bit) { (reg) ^= (1 << (uint8_t)(bit)); }
+
+
+// --- Bit manipulation with pointer to variable ---
+
+// Set n-th bit in pointee
+#define sbi_p(reg_p, bit) { (*(reg_p)) |=  (1 << (uint8_t)(bit)); }
+// Clear n-th bit in pointee
+#define cbi_p(reg_p, bit) { (*(reg_p)) &= ~(1 << (uint8_t)(bit)); }
+
+// Get n-th bit in pointee
+#define get_bit_p(reg_p, bit) ((*(reg_p) >> (uint8_t)(bit)) & 0x1)
+
+// Test n-th bit in pointee (Can't use bit_is_set, as it's redefined in sfr_def.h)
+#define bit_is_high_p(reg_p, bit) get_bit_p(reg_p, bit)
+#define bit_is_low_p(reg_p, bit)  (!get_bit_p(reg_p, bit))
+
+// Write value to a bit in pointee
+#define set_bit_p(reg_p, bit, value) { *(reg_p) = (*(reg_p) & ~(1 << ((uint8_t)(bit) & 0x1))) | (((uint8_t)(value) & 0x1) << (uint8_t)(bit)); }
+#define toggle_bit_p(reg_p, bit)     { *(reg_p) ^= (1 << (uint8_t)(bit)); }
+
+
+// --- Nibble manipulation ---
+
+// Replace nibble in a byte
+#define set_low_nibble(reg, value)  { (reg) = ((reg) & 0xF0) | ((uint8_t)(value) & 0xF); }
+#define set_high_nibble(reg, value) { (reg) = ((reg) & 0x0F) | (((uint8_t)(value) & 0xF) << 4); }
+
+#define set_low_nibble_p(reg_p, value)  { *(reg_p) = (*(reg_p) & 0xF0) | ((uint8_t)(value) & 0xF); }
+#define set_high_nibble_p(reg_p, value) { *(reg_p) = (*(reg_p) & 0x0F) | (((uint8_t)(value) & 0xF) << 4); }
+
+#define low_nibble(x) ((uint8_t)(x) & 0xF)
+#define high_nibble(x) (((uint8_t)(x) & 0xF0) >> 4)
+
+// --- Range tests ---
+
+// Test if X is within low..high, regardless of bounds order
+#define in_range(x, low, high)  ((((low)  < (high)) && ((x) >= (low) && (x)  < (high))) || (((low) > (high)) && ((x) >= (high) && (x)  < (low))))
+// ..., include greater bound
+#define in_rangei(x, low, high) ((((low) <= (high)) && ((x) >= (low) && (x) <= (high))) || (((low) > (high)) && ((x) >= (high) && (x) <= (low))))
+
+// Test if X in low..high, wrap around ends if needed.
+#define in_range_wrap(x, low, high)  ((((low)  < (high)) && ((x) >= (low) && (x) < (high)))  || (((low) > (high)) && ((x) >= (low) || (x)  < (high))))
+// ..., include upper bound
+#define in_range_wrapi(x, low, high) ((((low) <= (high)) && ((x) >= (low) && (x) <= (high))) || (((low) > (high)) && ((x) >= (low) || (x) <= (high))))

lib/porklib/color.c

@@ -0,0 +1,103 @@
+#include <avr/io.h>
+#include <util/delay.h>
+#include <stdint.h>
+
+#include "iopins.h"
+#include "nsdelay.h"
+#include "color.h"
+
+
+// --- HSL ---
+
+#ifdef HSL_LINEAR
+const uint8_t FADE_128[] =
+{
+	0,  1,  1,  1,  1,  1,  2,  2,  2,  2,  2,  3,  3,  3,  4,  4,  4,  4,
+	5,  5,  6,  6,  6,  7,  7,  8,  8,  8,  9,  10, 10, 10, 11, 12, 13, 14,
+	14, 15, 16, 17, 18, 20, 21, 22, 24, 26, 27, 28, 30, 31, 32, 34, 35, 36,
+	38, 39, 40, 41, 42, 44, 45, 46, 48, 49, 50, 52, 54, 56, 58, 59, 61, 63,
+	65, 67, 68, 69, 71, 72, 74, 76, 78, 80, 82, 85, 88, 90, 92, 95, 98, 100,
+	103, 106, 109, 112, 116, 119, 122, 125, 129, 134, 138, 142, 147, 151,
+	153, 156, 160, 163, 165, 170, 175, 180, 185, 190, 195, 200, 207, 214, 218,
+	221, 225, 228, 232, 234, 241, 248, 254, 255
+};
+#endif
+
+// based on: https://github.com/lewisd32/avr-hsl2rgb
+xrgb_t hsl_xrgb(const hsl_t cc)
+{
+	// 0 .. 256*3
+	const uint16_t hh = (uint16_t) cc.h * 3;
+	const uint8_t hue_mod = hh % 256;
+
+	uint8_t r_temp, g_temp, b_temp;
+	if (hh < 256)
+	{
+		r_temp = hue_mod ^ 255;
+		g_temp = hue_mod;
+		b_temp = 0;
+	}
+	else if (hh < 512)
+	{
+		r_temp = 0;
+		g_temp = hue_mod ^ 255;
+		b_temp = hue_mod;
+	}
+	else if (hh < 768)
+	{
+		r_temp = hue_mod;
+		g_temp = 0;
+		b_temp = hue_mod ^ 255;
+	}
+	else
+	{
+		r_temp = 0;
+		g_temp = 0;
+		b_temp = 0;
+	}
+
+	const uint8_t inverse_sat = (cc.s ^ 255);
+
+	xrgb_t rgb;
+
+	uint8_t t8;
+	uint16_t t16;
+
+#ifdef HSL_LINEAR
+	const uint8_t bri = FADE_128[cc.l >> 1];
+#else
+	const uint8_t bri = cc.l;
+#endif
+
+	t8 = r_temp;
+	t16 = t8 * cc.s + t8;
+	t16 = t16 + t8;
+	t8 = t16 >> 8;
+	t8 = t8 + inverse_sat;
+	t16 = t8 * bri;
+	t16 = t16 + t8;
+	t8 = t16 >> 8;
+	rgb.r = t8;
+
+	t8 = g_temp;
+	t16 = t8 * cc.s;
+	t16 = t16 + t8;
+	t8 = t16 >> 8;
+	t8 = t8 + inverse_sat;
+	t16 = t8 * bri;
+	t16 = t16 + t8;
+	t8 = t16 >> 8;
+	rgb.g = t8;
+
+	t8 = b_temp;
+	t16 = t8 * cc.s;
+	t16 = t16 + t8;
+	t8 = t16 >> 8;
+	t8 = t8 + inverse_sat;
+	t16 = t8 * bri;
+	t16 = t16 + t8;
+	t8 = t16 >> 8;
+	rgb.b = t8;
+
+	return rgb;
+}

lib/porklib/color.h

@@ -0,0 +1,57 @@
+#pragma once
+
+// --- color types ---
+//
+// The XXXc macros don't use cast, so they can be used in array initializers.
+//
+//  xrgb ... 3-byte true-color RGB (8 bits per component)
+//  rgb24 ... 24-bit color value, with equal nr of bits per component
+//
+//  XX_r (_g, _b) ... extract component from the color, and convert it to 0..255
+
+// Define HSL_LINEAR to get more linear brightness in hsl->rgb conversion
+
+
+typedef struct
+{
+	uint8_t r;
+	uint8_t g;
+	uint8_t b;
+} xrgb_t;
+
+
+typedef uint32_t rgb24_t;
+
+#define xrgb(rr, gg, bb) ((xrgb_t)xrgbc(rr, gg, bb))
+// xrgb for constant array declarations
+#define xrgbc(rr, gg, bb) { .r = ((uint8_t)(rr)), .g = ((uint8_t)(gg)), .b = ((uint8_t)(bb)) }
+#define xrgb_r(c) ((uint8_t)(c.r))
+#define xrgb_g(c) ((uint8_t)(c.g))
+#define xrgb_b(c) ((uint8_t)(c.b))
+#define xrgb_rgb24(c) ((((rgb24_t)c.r) << 16) | (((rgb24_t)c.g) << 8) | (((rgb24_t)c.b)))
+#define xrgb_rgb15(c) (((((rgb15_t)c.r) & 0xF8) << 7) | ((((rgb15_t)c.g) & 0xF8) << 2) | ((((rgb15_t)c.b) & 0xF8) >> 3))
+#define xrgb_rgb12(c) (((((rgb12_t)c.r) & 0xF0) << 4) | ((((rgb12_t)c.g) & 0xF0)) | ((((rgb12_t)c.b) & 0xF0) >> 4))
+#define xrgb_rgb6(c)  (((((rgb6_t)c.r) & 0xC0) >> 2)  | ((((rgb6_t)c.g) & 0xC0) >> 4) | ((((rgb6_t)c.b) & 0xC0) >> 6))
+
+#define rgb24c(r,g,b) (((((rgb24_t)r) & 0xFF) << 16) | ((((rgb24_t)g) & 0xFF) << 8) | (((rgb24_t)b) & 0xFF))
+#define rgb24(r,g,b) ((rgb24_t) rgb24(r,g,b))
+
+#define rgb24_r(c) ((((rgb24_t) (c)) >> 16) & 0xFF)
+#define rgb24_g(c) ((((rgb24_t) (c)) >> 8) & 0xFF)
+#define rgb24_b(c) ((((rgb24_t) (c)) >> 0) & 0xFF)
+#define rgb24_xrgb(c) xrgb(rgb24_r(c), rgb24_g(c), rgb24_b(c))
+#define rgb24_xrgbc(c) xrgbc(rgb24_r(c), rgb24_g(c), rgb24_b(c))
+
+#define add_xrgb(x, y) ((xrgb_t) { (((y).r > (255 - (x).r)) ? 255 : ((x).r + (y).r)), (((y).g > (255 - (x).g)) ? 255 : ((x).g + (y).g)), (((y).b > 255 - (x).b) ? 255 : ((x).b + (y).b)) })
+
+
+// HSL data structure
+typedef struct
+{
+	uint8_t h;
+	uint8_t s;
+	uint8_t l;
+} hsl_t;
+
+/* Convert HSL to XRGB */
+xrgb_t hsl_xrgb(const hsl_t color);

lib/porklib/debounce.c

@@ -0,0 +1,52 @@
+#include <avr/io.h>
+#include <stdbool.h>
+
+#include "debounce.h"
+#include "calc.h"
+#include "iopins.h"
+#include "debo_config.h"
+
+/** Debounce data array */
+uint8_t debo_next_slot = 0;
+
+uint8_t debo_register(PORT_P reg, uint8_t bit, bool invert)
+{
+	debo_slots[debo_next_slot] = (debo_slot_t)({
+		.reg = reg,
+		.bit = bit | ((invert & 1) << 7) | (get_bit_p(reg, bit) << 6), // bit 7 = invert, bit 6 = state
+		.count = 0,
+	});
+
+	return debo_next_slot++;
+}
+
+
+/** Check debounced pins, should be called periodically. */
+void debo_tick()
+{
+	for (uint8_t i = 0; i < debo_next_slot; i++)
+	{
+		// current pin value (right 3 bits, xored with inverse bit)
+		bool value = get_bit_p(debo_slots[i].reg, debo_slots[i].bit & 0x7);
+
+		if (value != get_bit(debo_slots[i].bit, 6))
+		{
+
+			// different pin state than last recorded state
+			if (debo_slots[i].count < DEBO_TICKS)
+			{
+				debo_slots[i].count++;
+			}
+			else
+			{
+				// overflown -> latch value
+				set_bit(debo_slots[i].bit, 6, value); // set state bit
+				debo_slots[i].count = 0;
+			}
+		}
+		else
+		{
+			debo_slots[i].count = 0; // reset the counter
+		}
+	}
+}

lib/porklib/debounce.h

@@ -0,0 +1,66 @@
+#pragma once
+
+//
+//  An implementation of button debouncer.
+//
+//  ----
+//
+//  You must provide a config file debo_config.h (next to your main.c)
+//
+//  A pin is registered like this:
+//
+//    #define BTN1 12 // pin D12
+//    #define BTN2 13
+//
+//    debo_add(BTN0);  // The function returns number assigned to the pin (0, 1, ...)
+//    debo_add_rev(BTN1);  // active low
+//    debo_register(&PINB, PB2, 0);  // direct access - register, pin & invert
+//
+//  Then periodically call the tick function (perhaps in a timer interrupt):
+//
+//    debo_tick();
+//
+//  To check if input is active, use
+//
+//    debo_get_pin(0); // state of input #0 (registered first)
+//    debo_get_pin(1); // state of input #1 (registered second)
+//
+
+
+#include <avr/io.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "calc.h"
+#include "iopins.h"
+
+// Your config file
+#include "debo_config.h"
+/*
+	#define DEBO_CHANNELS 2
+	#define DDEBO_TICKS 5
+*/
+
+
+/* Internal deboucer entry */
+typedef struct
+{
+	PORT_P reg;    // pointer to IO register
+	uint8_t bit;   // bits 6 and 7 of this hold "state" & "invert" flag
+	uint8_t count; // number of ticks this was in the new state
+} debo_slot_t;
+
+debo_slot_t debo_slots[DEBO_CHANNELS];
+
+/** Add a pin for debouncing (must be used with constant args) */
+#define debo_add_rev(pin) debo_register(&_pin(pin), _pn(pin), 1)
+#define debo_add(pin)  debo_register(&_pin(pin), _pn(pin), 0)
+
+/** Add a pin for debouncing (low level function) */
+uint8_t debo_register(PORT_P pin_reg_pointer, uint8_t bit, bool invert);
+
+/** Check debounced pins, should be called periodically. */
+void debo_tick();
+
+/** Get a value of debounced pin */
+#define debo_get_pin(i) (get_bit(debo_slots[i].bit, 6) ^ get_bit(debo_slots[i].bit, 7))

lib/porklib/dht11.c

@@ -0,0 +1,88 @@
+#include <avr/io.h>
+#include <util/delay.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "iopins.h"
+#include "dht11.h"
+
+/** Read one bit */
+bool _dht11_rxbit(const uint8_t pin)
+{
+	// Wait until start of pulse
+	while (is_low_n(pin));
+
+	uint8_t cnt = 0;
+	while (is_high_n(pin))
+	{
+		cnt++;
+		_delay_us(5);
+	}
+
+	return (cnt > 8);
+}
+
+
+/** Read one byte */
+uint8_t _dht11_rxbyte(const uint8_t pin)
+{
+	uint8_t byte = 0;
+
+	for (uint8_t i = 0; i < 8; i++)
+	{
+		if (_dht11_rxbit(pin))
+			byte |= (1 << (7 - i));
+	}
+
+	return byte;
+}
+
+
+/** Read tehmperature and humidity from the DHT11, returns false on failure */
+bool dht11_read(const uint8_t pin, dht11_result_t* result)
+{
+	// bus down for > 18 ms
+	as_output_n(pin);
+	pin_low_n(pin);
+	_delay_ms(20);
+
+	// bus up for 20-40us
+	pin_high_n(pin);
+	_delay_us(20);
+
+	// release
+	as_input_pu_n(pin);
+
+	// DHT should send 80us LOW & 80us HIGH
+
+	_delay_us(40);
+	if (!is_low_n(pin))
+		return false; // init error
+
+	_delay_us(80);
+	if (!is_high_n(pin))
+		return false; // init error
+
+	// skip to start of first bit
+	_delay_us(50);
+
+	// Receive 5 data bytes (Rh int, Rh dec, Temp int, Temp dec, Checksum)
+	// Decimal bytes are zero for DHT11 -> we can ignore them.
+	uint8_t bytes[5];
+	uint8_t sum = 0;
+
+	for (uint8_t i = 0; i < 5; i++)
+	{
+		uint8_t b = _dht11_rxbyte(pin);
+		bytes[i] = b;
+		if (i < 4) sum += b;
+	}
+
+	// Verify checksum
+	if (sum != bytes[4]) return false;
+
+	result->rh = bytes[0];
+	result->temp = bytes[2];
+
+	return true;
+}

lib/porklib/dht11.h

@@ -0,0 +1,17 @@
+#pragma once
+
+//
+// Reading temperature and relative humidity from DHT11
+//
+
+#include <stdint.h>
+#include <stdbool.h>
+
+typedef struct
+{
+	int8_t temp;
+	int8_t rh;
+} dht11_result_t;
+
+/** Read tehmperature and humidity from the DHT11, returns false on failure */
+bool dht11_read(const uint8_t pin, dht11_result_t* result);

lib/porklib/fat16.h

@@ -0,0 +1,276 @@
+#pragma once
+
+//
+// Simple FAT16 library.
+//
+// To use it, implement BLOCKDEV functions
+// and attach them to it's instance.
+//
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "blockdev.h"
+
+
+// -------------------------------
+
+/**
+ * File types (values can be used for debug printing).
+ * Accessible using file->type
+ */
+typedef enum
+{
+	FT_NONE = '-',
+	FT_DELETED = 'x',
+	FT_SUBDIR = 'D',
+	FT_PARENT = 'P',
+	FT_LABEL = 'L',
+	FT_LFN = '~',
+	FT_INVALID = '?', // not recognized weird file
+	FT_SELF = '.',
+	FT_FILE = 'F'
+} FAT16_FT;
+
+
+/** "File address" for saving and restoring file */
+typedef struct
+{
+	uint16_t clu;
+	uint16_t num;
+	uint32_t cur_rel;
+} FSAVEPOS;
+
+
+// Include definitions of fully internal structs
+#include "fat16_internal.h"
+
+
+/**
+ * File handle struct.
+ *
+ * File handle contains cursor, file name, type, size etc.
+ * Everything (files, dirs) is accessed using this.
+ */
+typedef struct __attribute__((packed))
+{
+	/**
+	 * Raw file name. Starting 0x05 was converted to 0xE5.
+	 * To get PRINTABLE file name, use fat16_dispname()
+	 */
+	uint8_t name[11];
+
+	/**
+	 * File attributes - bit field composed of FA_* flags
+	 * (internal)
+	 */
+	uint8_t attribs;
+
+	// 14 bytes skipped (10 reserved, date, time)
+
+	/** First cluster of the file. (internal) */
+	uint16_t clu_start;
+
+	/**
+	 * File size in bytes.
+	 * This is the current allocated and readable file size.
+	 */
+	uint32_t size;
+
+
+	// --- the following fields are added when reading ---
+
+	/** File type. */
+	FAT16_FT type;
+
+
+	// --- INTERNAL FIELDS ---
+
+	// Cursor variables. (internal)
+	uint32_t cur_abs; // absolute position in device
+	uint32_t cur_rel; // relative position in file
+	uint16_t cur_clu; // cluster where the cursor is
+	uint16_t cur_ofs; // offset within the active cluster
+
+	// File position in the directory. (internal)
+	uint16_t clu; // first cluster of directory
+	uint16_t num; // file entry number
+
+	// Pointer to the FAT16 handle. (internal)
+	const FAT16* fat;
+}
+FFILE;
+
+
+/**
+ * Store modified file metadata and flush it to disk.
+ */
+void ff_flush_file(FFILE* file);
+
+
+/**
+ * Save a file "position" into a struct, for later restoration.
+ * Cursor is also saved.
+ */
+FSAVEPOS ff_savepos(const FFILE* file);
+
+/**
+ * Restore a file from a saved position.
+ */
+void ff_reopen(FFILE* file, const FSAVEPOS* pos);
+
+
+/**
+ * Initialize the file system - store into "fat"
+ */
+bool ff_init(const BLOCKDEV* dev, FAT16* fat);
+
+
+/**
+ * Open the first file of the root directory.
+ * The file may be invalid (eg. a volume label, deleted etc),
+ * or blank (type FT_NONE) if the filesystem is empty.
+ */
+void ff_root(const FAT16* fat, FFILE* file);
+
+
+/**
+ * Resolve the disk label.
+ * That can be in the Boot Sector, or in the first root directory entry.
+ *
+ * @param fat       the FAT handle
+ * @param label_out string to store the label in. Should have at least 12 bytes.
+ */
+char* ff_disk_label(const FAT16* fat, char* label_out);
+
+
+// ----------- FILE I/O -------------
+
+
+/**
+ * Move file cursor to a position relative to file start
+ * Returns false on I/O error (bad file, out of range...)
+ */
+bool ff_seek(FFILE* file, uint32_t addr);
+
+
+/**
+ * Read bytes from file into memory
+ * Returns number of bytes read, 0 on error.
+ */
+uint16_t ff_read(FFILE* file, void* target, uint16_t len);
+
+
+/**
+ * Write into file at a "seek" position.
+ */
+bool ff_write(FFILE* file, const void* source, uint32_t len);
+
+
+/**
+ * Store a 0-terminated string at cursor.
+ */
+bool ff_write_str(FFILE* file, const char* source);
+
+
+/**
+ * Create a new file in given folder
+ *
+ * file ... open directory; new file is opened into this handle.
+ * name ... name of the new file, including extension
+ */
+bool ff_newfile(FFILE* file, const char* name);
+
+
+/**
+ * Create a sub-directory of given name.
+ * Directory is allocated and populated with entries "." and ".."
+ */
+bool ff_mkdir(FFILE* file, const char* name);
+
+
+/**
+ * Set new file size.
+ * Allocates / frees needed clusters, does NOT erase them.
+ *
+ * Useful mainly for shrinking.
+ */
+void set_file_size(FFILE* file, uint32_t size);
+
+
+/**
+ * Delete a *FILE* and free it's clusters.
+ */
+bool ff_rmfile(FFILE* file);
+
+
+/**
+ * Delete an empty *DIRECTORY* and free it's clusters.
+ */
+bool ff_rmdir(FFILE* file);
+
+
+/**
+ * Delete a file or directory, even FT_LFN and FT_INVALID.
+ * Directories are deleted recursively (!)
+ */
+bool ff_delete(FFILE* file);
+
+
+
+// --------- NAVIGATION ------------
+
+
+/** Go to previous file in the directory (false = no prev file) */
+bool ff_prev(FFILE* file);
+
+
+/** Go to next file in directory (false = no next file) */
+bool ff_next(FFILE* file);
+
+
+/**
+ * Open a subdirectory denoted by the file.
+ * Provided handle changes to the first entry of the directory.
+ */
+bool ff_opendir(FFILE* dir);
+
+
+/**
+ * Open a parent directory. Fails in root.
+ * Provided handle changes to the first entry of the parent directory.
+ */
+bool ff_parent(FFILE* file);
+
+
+/** Jump to first file in this directory */
+void ff_first(FFILE* file);
+
+
+/**
+ * Find a file with given "display name" in this directory, and open it.
+ * If file is found, "file" will contain it's handle.
+ * Otherwise, the handle is unchanged.
+ */
+bool ff_find(FFILE* file, const char* name);
+
+
+// -------- FILE INSPECTION -----------
+
+/** Check if file is a valid entry, or long-name/label/deleted */
+bool ff_is_regular(const FFILE* file);
+
+
+/**
+ * Resolve a file name, trim spaces and add null terminator.
+ * Returns the passed char*, or NULL on error.
+ */
+char* ff_dispname(const FFILE* file, char* disp_out);
+
+
+/**
+ * Convert filename to zero-padded fixed length one
+ * Returns the passed char*.
+ */
+char* ff_rawname(const char* disp_in, char* raw_out);
+

lib/porklib/fat16_internal.h

@@ -0,0 +1,64 @@
+#pragma once
+
+#include <stdint.h>
+#include <stdbool.h>
+
+// Internal types and stuff that is needed in the header for declarations,
+// but is not a part of the public API.
+
+/** Boot Sector structure */
+typedef struct __attribute__((packed))
+{
+	// Fields loaded directly from disk:
+
+	// 13 bytes skipped
+	uint8_t sectors_per_cluster;
+	uint16_t reserved_sectors;
+	uint8_t num_fats;
+	uint16_t root_entries;
+	// 3 bytes skipped
+	uint16_t fat_size_sectors;
+	// 8 bytes skipped
+	uint32_t total_sectors; // if "short size sectors" is used, it's copied here too
+	// 7 bytes skipped
+	char volume_label[11]; // space padded, no terminator
+
+	// Added fields:
+
+	uint32_t bytes_per_cluster;
+
+}
+Fat16BootSector;
+
+
+/** FAT filesystem handle */
+typedef struct __attribute__((packed))
+{
+	// Backing block device
+	const BLOCKDEV* dev;
+
+	// Root directory sector start
+	uint32_t rd_addr;
+
+	// Start of first cluster (number "2")
+	uint32_t data_addr;
+
+	// Start of fat table
+	uint32_t fat_addr;
+
+	// Boot sector data struct
+	Fat16BootSector bs;
+}
+FAT16;
+
+
+/**
+ * File Attributes (bit flags)
+ * Accessible using file->attribs
+ */
+#define FA_READONLY 0x01 // read only file
+#define FA_HIDDEN   0x02 // hidden file
+#define FA_SYSTEM   0x04 // system file
+#define FA_LABEL    0x08 // volume label entry, found only in root directory.
+#define FA_DIR      0x10 // subdirectory
+#define FA_ARCHIVE  0x20 // archive flag

lib/porklib/iopins.c

@@ -0,0 +1,276 @@
+#include <avr/io.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "calc.h"
+#include "iopins.h"
+
+
+void set_dir_n(const uint8_t pin, const uint8_t d)
+{
+	switch(pin) {
+		case 0: set_dir(0, d); return;
+		case 1: set_dir(1, d); return;
+		case 2: set_dir(2, d); return;
+		case 3: set_dir(3, d); return;
+		case 4: set_dir(4, d); return;
+		case 5: set_dir(5, d); return;
+		case 6: set_dir(6, d); return;
+		case 7: set_dir(7, d); return;
+		case 8: set_dir(8, d); return;
+		case 9: set_dir(9, d); return;
+		case 10: set_dir(10, d); return;
+		case 11: set_dir(11, d); return;
+		case 12: set_dir(12, d); return;
+		case 13: set_dir(13, d); return;
+		case 14: set_dir(14, d); return;
+		case 15: set_dir(15, d); return;
+		case 16: set_dir(16, d); return;
+		case 17: set_dir(17, d); return;
+		case 18: set_dir(18, d); return;
+		case 19: set_dir(19, d); return;
+		case 20: set_dir(20, d); return;
+		case 21: set_dir(21, d); return;
+	}
+}
+
+void as_input_n(const uint8_t pin)
+{
+	switch(pin) {
+		case 0: as_input(0); return;
+		case 1: as_input(1); return;
+		case 2: as_input(2); return;
+		case 3: as_input(3); return;
+		case 4: as_input(4); return;
+		case 5: as_input(5); return;
+		case 6: as_input(6); return;
+		case 7: as_input(7); return;
+		case 8: as_input(8); return;
+		case 9: as_input(9); return;
+		case 10: as_input(10); return;
+		case 11: as_input(11); return;
+		case 12: as_input(12); return;
+		case 13: as_input(13); return;
+		case 14: as_input(14); return;
+		case 15: as_input(15); return;
+		case 16: as_input(16); return;
+		case 17: as_input(17); return;
+		case 18: as_input(18); return;
+		case 19: as_input(19); return;
+		case 20: as_input(20); return;
+		case 21: as_input(21); return;
+	}
+}
+
+
+void as_input_pu_n(const uint8_t pin)
+{
+	switch(pin) {
+		case 0: as_input_pu(0); return;
+		case 1: as_input_pu(1); return;
+		case 2: as_input_pu(2); return;
+		case 3: as_input_pu(3); return;
+		case 4: as_input_pu(4); return;
+		case 5: as_input_pu(5); return;
+		case 6: as_input_pu(6); return;
+		case 7: as_input_pu(7); return;
+		case 8: as_input_pu(8); return;
+		case 9: as_input_pu(9); return;
+		case 10: as_input_pu(10); return;
+		case 11: as_input_pu(11); return;
+		case 12: as_input_pu(12); return;
+		case 13: as_input_pu(13); return;
+		case 14: as_input_pu(14); return;
+		case 15: as_input_pu(15); return;
+		case 16: as_input_pu(16); return;
+		case 17: as_input_pu(17); return;
+		case 18: as_input_pu(18); return;
+		case 19: as_input_pu(19); return;
+		case 20: as_input_pu(20); return;
+		case 21: as_input_pu(21); return;
+	}
+}
+
+
+void as_output_n(const uint8_t pin)
+{
+	switch(pin) {
+		case 0: as_output(0); return;
+		case 1: as_output(1); return;
+		case 2: as_output(2); return;
+		case 3: as_output(3); return;
+		case 4: as_output(4); return;
+		case 5: as_output(5); return;
+		case 6: as_output(6); return;
+		case 7: as_output(7); return;
+		case 8: as_output(8); return;
+		case 9: as_output(9); return;
+		case 10: as_output(10); return;
+		case 11: as_output(11); return;
+		case 12: as_output(12); return;
+		case 13: as_output(13); return;
+		case 14: as_output(14); return;
+		case 15: as_output(15); return;
+		case 16: as_output(16); return;
+		case 17: as_output(17); return;
+		case 18: as_output(18); return;
+		case 19: as_output(19); return;
+		case 20: as_output(20); return;
+		case 21: as_output(21); return;
+	}
+}
+
+void set_pin_n(const uint8_t pin, const uint8_t v)
+{
+	switch(pin) {
+		case 0: set_pin(0, v); return;
+		case 1: set_pin(1, v); return;
+		case 2: set_pin(2, v); return;
+		case 3: set_pin(3, v); return;
+		case 4: set_pin(4, v); return;
+		case 5: set_pin(5, v); return;
+		case 6: set_pin(6, v); return;
+		case 7: set_pin(7, v); return;
+		case 8: set_pin(8, v); return;
+		case 9: set_pin(9, v); return;
+		case 10: set_pin(10, v); return;
+		case 11: set_pin(11, v); return;
+		case 12: set_pin(12, v); return;
+		case 13: set_pin(13, v); return;
+		case 14: set_pin(14, v); return;
+		case 15: set_pin(15, v); return;
+		case 16: set_pin(16, v); return;
+		case 17: set_pin(17, v); return;
+		case 18: set_pin(18, v); return;
+		case 19: set_pin(19, v); return;
+		case 20: set_pin(20, v); return;
+		case 21: set_pin(21, v); return;
+	}
+}
+
+void pin_low_n(const uint8_t pin)
+{
+	switch(pin) {
+		case 0: pin_low(0); return;
+		case 1: pin_low(1); return;
+		case 2: pin_low(2); return;
+		case 3: pin_low(3); return;
+		case 4: pin_low(4); return;
+		case 5: pin_low(5); return;
+		case 6: pin_low(6); return;
+		case 7: pin_low(7); return;
+		case 8: pin_low(8); return;
+		case 9: pin_low(9); return;
+		case 10: pin_low(10); return;
+		case 11: pin_low(11); return;
+		case 12: pin_low(12); return;
+		case 13: pin_low(13); return;
+		case 14: pin_low(14); return;
+		case 15: pin_low(15); return;
+		case 16: pin_low(16); return;
+		case 17: pin_low(17); return;
+		case 18: pin_low(18); return;
+		case 19: pin_low(19); return;
+		case 20: pin_low(20); return;
+		case 21: pin_low(21); return;
+	}
+}
+
+void pin_high_n(const uint8_t pin)
+{
+	switch(pin) {
+		case 0: pin_high(0); return;
+		case 1: pin_high(1); return;
+		case 2: pin_high(2); return;
+		case 3: pin_high(3); return;
+		case 4: pin_high(4); return;
+		case 5: pin_high(5); return;
+		case 6: pin_high(6); return;
+		case 7: pin_high(7); return;
+		case 8: pin_high(8); return;
+		case 9: pin_high(9); return;
+		case 10: pin_high(10); return;
+		case 11: pin_high(11); return;
+		case 12: pin_high(12); return;
+		case 13: pin_high(13); return;
+		case 14: pin_high(14); return;
+		case 15: pin_high(15); return;
+		case 16: pin_high(16); return;
+		case 17: pin_high(17); return;
+		case 18: pin_high(18); return;
+		case 19: pin_high(19); return;
+		case 20: pin_high(20); return;
+		case 21: pin_high(21); return;
+	}
+}
+
+
+void toggle_pin_n(const uint8_t pin)
+{
+	switch(pin) {
+		case 0: toggle_pin(0); return;
+		case 1: toggle_pin(1); return;
+		case 2: toggle_pin(2); return;
+		case 3: toggle_pin(3); return;
+		case 4: toggle_pin(4); return;
+		case 5: toggle_pin(5); return;
+		case 6: toggle_pin(6); return;
+		case 7: toggle_pin(7); return;
+		case 8: toggle_pin(8); return;
+		case 9: toggle_pin(9); return;
+		case 10: toggle_pin(10); return;
+		case 11: toggle_pin(11); return;
+		case 12: toggle_pin(12); return;
+		case 13: toggle_pin(13); return;
+		case 14: toggle_pin(14); return;
+		case 15: toggle_pin(15); return;
+		case 16: toggle_pin(16); return;
+		case 17: toggle_pin(17); return;
+		case 18: toggle_pin(18); return;
+		case 19: toggle_pin(19); return;
+		case 20: toggle_pin(20); return;
+		case 21: toggle_pin(21); return;
+	}
+}
+
+
+bool get_pin_n(const uint8_t pin)
+{
+	switch(pin) {
+		case 0: return get_pin(0);
+		case 1: return get_pin(1);
+		case 2: return get_pin(2);
+		case 3: return get_pin(3);
+		case 4: return get_pin(4);
+		case 5: return get_pin(5);
+		case 6: return get_pin(6);
+		case 7: return get_pin(7);
+		case 8: return get_pin(8);
+		case 9: return get_pin(9);
+		case 10: return get_pin(10);
+		case 11: return get_pin(11);
+		case 12: return get_pin(12);
+		case 13: return get_pin(13);
+		case 14: return get_pin(14);
+		case 15: return get_pin(15);
+		case 16: return get_pin(16);
+		case 17: return get_pin(17);
+		case 18: return get_pin(18);
+		case 19: return get_pin(19);
+		case 20: return get_pin(20);
+		case 21: return get_pin(21);
+	}
+	return false;
+}
+
+
+bool is_low_n(const uint8_t pin)
+{
+	return !get_pin_n(pin);
+}
+
+
+bool is_high_n(const uint8_t pin)
+{
+	return get_pin_n(pin);
+}

lib/porklib/iopins.h

@@ -0,0 +1,213 @@
+#pragma once
+
+//
+// * Utilities for pin aliasing / numbering. *
+//
+// Designed for Arduino.
+//
+// If you know the pin number beforehand, you can use the macros.
+//
+// If you need to use a variable for pin number, use the `_n` functions.
+// They are much slower, so always check if you really need them
+// - and they aren't fit for things where precise timing is required.
+//
+
+#include <avr/io.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "calc.h"
+
+
+// type: pointer to port
+typedef volatile uint8_t* PORT_P;
+
+
+/** Pin numbering reference */
+#define D0 0
+#define D1 1
+#define D2 2
+#define D3 3
+#define D4 4
+#define D5 5
+#define D6 6
+#define D7 7
+#define D8 8
+#define D9 9
+#define D10 10
+#define D11 11
+#define D12 12
+#define D13 13
+#define D14 14
+#define D15 15
+#define D16 16
+#define D17 17
+#define D18 18
+#define D19 19
+#define D20 20
+#define D21 21
+#define A0 14
+#define A1 15
+#define A2 16
+#define A3 17
+#define A4 18
+#define A5 19
+#define A6 20
+#define A7 21
+
+
+#define _ddr(pin)  _DDR_##pin
+#define _pin(pin)  _PIN_##pin
+#define _pn(pin)   _PN_##pin
+#define _port(pin) _PORT_##pin
+
+
+/** Set pin direction */
+#define set_dir(pin, d)  set_bit( _ddr(pin), _pn(pin), d )
+void    set_dir_n(const uint8_t pin, const uint8_t d);
+
+
+/** Configure pin as input */
+#define as_input(pin)    cbi( _ddr(pin), _pn(pin) )
+void    as_input_n(const uint8_t pin);
+
+
+/** Configure pin as input, with pull-up enabled */
+#define as_input_pu(pin) { as_input(pin); pin_high(pin); }
+void    as_input_pu_n(const uint8_t pin);
+
+
+/** Configure pin as output */
+#define as_output(pin)   sbi( _ddr(pin), _pn(pin) )
+void    as_output_n(const uint8_t pin);
+
+
+/** Write value to a pin */
+#define set_pin(pin, v) set_bit( _port(pin), _pn(pin), v )
+void    set_pin_n(const uint8_t pin, const uint8_t v);
+
+
+/** Write 0 to a pin */
+#define pin_low(pin)    cbi( _port(pin), _pn(pin) )
+void    pin_low_n(const uint8_t pin);
+
+
+/** Write 1 to a pin */
+#define pin_high(pin)   sbi( _port(pin), _pn(pin) )
+void    pin_high_n(const uint8_t pin);
+
+
+/** Toggle a pin state */
+#define toggle_pin(pin)   sbi( _pin(pin), _pn(pin) )
+void    toggle_pin_n(const uint8_t pin);
+
+
+/** Read a pin value */
+#define get_pin(pin)  get_bit( _pin(pin), _pn(pin) )
+bool    get_pin_n(const uint8_t pin);
+
+
+/** CHeck if pin is low */
+#define is_low(pin)   (get_pin(pin) == 0)
+bool    is_low_n(const uint8_t pin);
+
+
+/** CHeck if pin is high */
+#define is_high(pin)  (get_pin(pin) != 0)
+bool    is_high_n(const uint8_t pin);
+
+
+
+// Helper macros
+
+#define _PORT_0  PORTD
+#define _PORT_1  PORTD
+#define _PORT_2  PORTD
+#define _PORT_3  PORTD
+#define _PORT_4  PORTD
+#define _PORT_5  PORTD
+#define _PORT_6  PORTD
+#define _PORT_7  PORTD
+#define _PORT_8  PORTB
+#define _PORT_9  PORTB
+#define _PORT_10 PORTB
+#define _PORT_11 PORTB
+#define _PORT_12 PORTB
+#define _PORT_13 PORTB
+#define _PORT_14 PORTC
+#define _PORT_15 PORTC
+#define _PORT_16 PORTC
+#define _PORT_17 PORTC
+#define _PORT_18 PORTC
+#define _PORT_19 PORTC
+#define _PORT_20 PORTC
+#define _PORT_21 PORTC
+
+#define _PIN_0  PIND
+#define _PIN_1  PIND
+#define _PIN_2  PIND
+#define _PIN_3  PIND
+#define _PIN_4  PIND
+#define _PIN_5  PIND
+#define _PIN_6  PIND
+#define _PIN_7  PIND
+#define _PIN_8  PINB
+#define _PIN_9  PINB
+#define _PIN_10 PINB
+#define _PIN_11 PINB
+#define _PIN_12 PINB
+#define _PIN_13 PINB
+#define _PIN_14 PINC
+#define _PIN_15 PINC
+#define _PIN_16 PINC
+#define _PIN_17 PINC
+#define _PIN_18 PINC
+#define _PIN_19 PINC
+#define _PIN_20 PINC
+#define _PIN_21 PINC
+
+#define _DDR_0  DDRD
+#define _DDR_1  DDRD
+#define _DDR_2  DDRD
+#define _DDR_3  DDRD
+#define _DDR_4  DDRD
+#define _DDR_5  DDRD
+#define _DDR_6  DDRD
+#define _DDR_7  DDRD
+#define _DDR_8  DDRB
+#define _DDR_9  DDRB
+#define _DDR_10 DDRB
+#define _DDR_11 DDRB
+#define _DDR_12 DDRB
+#define _DDR_13 DDRB
+#define _DDR_14 DDRC
+#define _DDR_15 DDRC
+#define _DDR_16 DDRC
+#define _DDR_17 DDRC
+#define _DDR_18 DDRC
+#define _DDR_19 DDRC
+#define _DDR_20 DDRC
+#define _DDR_21 DDRC
+
+#define _PN_0  0
+#define _PN_1  1
+#define _PN_2  2
+#define _PN_3  3
+#define _PN_4  4
+#define _PN_5  5
+#define _PN_6  6
+#define _PN_7  7
+#define _PN_8  0
+#define _PN_9  1
+#define _PN_10 2
+#define _PN_11 3
+#define _PN_12 4
+#define _PN_13 5
+#define _PN_14 0
+#define _PN_15 1
+#define _PN_16 2
+#define _PN_17 3
+#define _PN_18 4
+#define _PN_19 5
+#define _PN_20 6
+#define _PN_21 7

lib/porklib/lcd.c

@@ -0,0 +1,365 @@
+#include <stdbool.h>
+#include <stdint.h>
+#include <avr/io.h>
+#include <avr/pgmspace.h>
+#include <util/delay.h>
+
+#include "calc.h"
+#include "iopins.h"
+#include "nsdelay.h"
+#include "lcd.h"
+#include "lcd_config.h"
+
+// Start address of rows
+const uint8_t LCD_ROW_ADDR[] = {0x00, 0x40, 0x14, 0x54};
+
+
+// Shared stream instance
+static STREAM _lcd_singleton;
+STREAM* lcd;
+
+
+// Internal prototypes
+void _lcd_mode_r();
+void _lcd_mode_w();
+void _lcd_clk();
+void _lcd_wait_bf();
+void _lcd_write_byte(uint8_t bb);
+uint8_t _lcd_read_byte();
+
+
+// Write utilities
+#define _lcd_write_low(bb)  _lcd_write_nibble((bb) & 0x0F)
+#define _lcd_write_high(bb) _lcd_write_nibble(((bb) & 0xF0) >> 4)
+#define _lcd_write_nibble(nib) do {                \
+	set_pin(LCD_D7, get_bit((nib), 3));     \
+	set_pin(LCD_D6, get_bit((nib), 2));     \
+	set_pin(LCD_D5, get_bit((nib), 1));     \
+	set_pin(LCD_D4, get_bit((nib), 0));     \
+} while(0)
+
+
+// 0 W, 1 R
+bool _lcd_mode;
+
+struct
+{
+	uint8_t x;
+	uint8_t y;
+} _pos;
+
+enum
+{
+	TEXT = 0,
+	CG = 1
+} _addrtype;
+
+
+/** Initialize the display */
+void lcd_init()
+{
+	// configure pins as output
+	as_output(LCD_E);
+	as_output(LCD_RW);
+	as_output(LCD_RS);
+	_lcd_mode = 1;  // force data pins to output
+	_lcd_mode_w();
+
+	// Magic sequence to invoke Cthulhu (or enter 4-bit mode)
+	_delay_ms(16);
+	_lcd_write_nibble(0b0011);
+	_lcd_clk();
+	_delay_ms(5);
+	_lcd_clk();
+	_delay_ms(5);
+	_lcd_clk();
+	_delay_ms(5);
+	_lcd_write_nibble(0b0010);
+	_lcd_clk();
+	_delay_us(100);
+
+	// Configure the display
+	lcd_command(LCD_IFACE_4BIT_2LINE);
+	lcd_command(LCD_DISABLE);
+	lcd_command(LCD_CLEAR);
+	lcd_command(LCD_MODE_INC);
+
+	// mark as enabled
+	lcd_enable();
+
+	_lcd_singleton.tx = &lcd_write;
+	_lcd_singleton.rx = &lcd_read;
+
+	// Stream
+	lcd = &_lcd_singleton;
+
+	_pos.x = 0;
+	_pos.y = 0;
+	_addrtype = TEXT;
+}
+
+
+/** Send a pulse on the ENABLE line */
+void _lcd_clk()
+{
+	pin_high(LCD_E);
+	delay_ns(450);
+	pin_low(LCD_E);
+}
+
+
+/** Enter READ mode */
+void _lcd_mode_r()
+{
+	if (_lcd_mode == 1) return;  // already in R mode
+
+	pin_high(LCD_RW);
+
+	as_input_pu(LCD_D7);
+	as_input_pu(LCD_D6);
+	as_input_pu(LCD_D5);
+	as_input_pu(LCD_D4);
+
+	_lcd_mode = 1;
+}
+
+
+/** Enter WRITE mode */
+void _lcd_mode_w()
+{
+	if (_lcd_mode == 0) return;  // already in W mode
+
+	pin_low(LCD_RW);
+
+	as_output(LCD_D7);
+	as_output(LCD_D6);
+	as_output(LCD_D5);
+	as_output(LCD_D4);
+
+	_lcd_mode = 0;
+}
+
+
+/** Read a byte */
+uint8_t _lcd_read_byte()
+{
+	_lcd_mode_r();
+
+	uint8_t res = 0;
+
+	_lcd_clk();
+	res = (get_pin(LCD_D7) << 7) | (get_pin(LCD_D6) << 6) | (get_pin(LCD_D5) << 5) | (get_pin(LCD_D4) << 4);
+
+	_lcd_clk();
+	res |= (get_pin(LCD_D7) << 3) | (get_pin(LCD_D6) << 2) | (get_pin(LCD_D5) << 1) | (get_pin(LCD_D4) << 0);
+
+	return res;
+}
+
+
+/** Write an instruction byte */
+void lcd_command(uint8_t bb)
+{
+	_lcd_wait_bf();
+	pin_low(LCD_RS);  // select instruction register
+	_lcd_write_byte(bb);    // send instruction byte
+}
+
+
+/** Write a data byte */
+void lcd_write(uint8_t bb)
+{
+	if (_addrtype == TEXT)
+	{
+		if (bb == '\r')
+		{
+			// CR
+			_pos.x = 0;
+			lcd_xy(_pos.x, _pos.y);
+			return;
+		}
+
+		if (bb == '\n')
+		{
+			// LF
+			_pos.y++;
+			lcd_xy(_pos.x, _pos.y);
+			return;
+		}
+
+		_pos.x++;
+	}
+
+	_lcd_wait_bf();
+	pin_high(LCD_RS);  // select data register
+	_lcd_write_byte(bb);  // send data byte
+}
+
+
+/** Read BF & Address */
+uint8_t lcd_read_bf_addr()
+{
+	pin_low(LCD_RS);
+	return _lcd_read_byte();
+}
+
+
+/** Read CGRAM or DDRAM */
+uint8_t lcd_read()
+{
+	if (_addrtype == TEXT) _pos.x++;
+
+	pin_high(LCD_RS);
+	return _lcd_read_byte();
+}
+
+
+/** Write a byte using the 4-bit interface */
+void _lcd_write_byte(uint8_t bb)
+{
+	_lcd_mode_w();  // enter W mode
+
+	_lcd_write_high(bb);
+	_lcd_clk();
+
+	_lcd_write_low(bb);
+	_lcd_clk();
+}
+
+
+
+/** Wait until the device is ready */
+void _lcd_wait_bf()
+{
+	uint8_t d = 0;
+	while (d++ < 120 && lcd_read_bf_addr() & _BV(7))
+		_delay_us(1);
+}
+
+
+/** Send a string to LCD */
+void lcd_puts(char* str_p)
+{
+	char c;
+	while ((c = *str_p++))
+		lcd_putc(c);
+}
+
+
+/** Print from progmem */
+void lcd_puts_P(const char* str_p)
+{
+	char c;
+	while ((c = pgm_read_byte(str_p++)))
+		lcd_putc(c);
+}
+
+
+/** Sedn a char to LCD */
+void lcd_putc(const char c)
+{
+	lcd_write(c);
+}
+
+
+/** Set cursor position */
+void lcd_xy(const uint8_t x, const uint8_t y)
+{
+	_pos.x = x;
+	_pos.y = y;
+	lcd_addr(LCD_ROW_ADDR[y] + (x));
+}
+
+
+uint8_t _lcd_old_cursor = CURSOR_NONE;
+bool _lcd_enabled = false;
+
+/** Set LCD cursor. If not enabled, only remember it. */
+void lcd_cursor(uint8_t type)
+{
+	_lcd_old_cursor = (type & CURSOR_BOTH);
+
+	if (_lcd_enabled) lcd_command(LCD_CURSOR_NONE | _lcd_old_cursor);
+}
+
+
+/** Display display (preserving cursor) */
+void lcd_disable()
+{
+	lcd_command(LCD_DISABLE);
+	_lcd_enabled = false;
+}
+
+
+/** Enable display (restoring cursor) */
+void lcd_enable()
+{
+	_lcd_enabled = true;
+	lcd_cursor(_lcd_old_cursor);
+}
+
+
+/** Go home */
+void lcd_home()
+{
+	lcd_command(LCD_HOME);
+	_pos.x = 0;
+	_pos.y = 0;
+	_addrtype = TEXT;
+}
+
+
+/** Clear the screen */
+void lcd_clear()
+{
+	lcd_command(LCD_CLEAR);
+	_pos.x = 0;
+	_pos.y = 0;
+	_addrtype = TEXT;
+}
+
+
+/** Define a glyph */
+void lcd_glyph(const uint8_t index, const uint8_t* array)
+{
+	lcd_addr_cg(index * 8);
+	for (uint8_t i = 0; i < 8; ++i)
+	{
+		lcd_write(array[i]);
+	}
+
+	// restore previous position
+	lcd_xy(_pos.x, _pos.y);
+	_addrtype = TEXT;
+}
+
+
+/** Define a glyph */
+void lcd_glyph_P(const uint8_t index, const uint8_t* array)
+{
+	lcd_addr_cg(index * 8);
+	for (uint8_t i = 0; i < 8; ++i)
+	{
+		lcd_write(pgm_read_byte(&array[i]));
+	}
+
+	// restore previous position
+	lcd_xy(_pos.x, _pos.y);
+	_addrtype = TEXT;
+}
+
+
+/** Set address in CGRAM */
+void lcd_addr_cg(const uint8_t acg)
+{
+	_addrtype = CG;
+	lcd_command(0b01000000 | ((acg) & 0b00111111));
+}
+
+
+/** Set address in DDRAM */
+void lcd_addr(const uint8_t add)
+{
+	_addrtype = TEXT;
+	lcd_command(0b10000000 | ((add) & 0b01111111));
+}

lib/porklib/lcd.h

@@ -0,0 +1,146 @@
+#pragma once
+
+//  HD44780 LCD display driver - 4-bit mode
+//
+//  LCD pins are configured using a file lcd_config.h, which you
+//  have to add next to your main.c file.
+//
+//  Content can be something like this:
+//
+//
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "stream.h"
+
+// Your file with configs
+#include "lcd_config.h"
+/*
+	#define LCD_RS 10
+	#define LCD_RW 11
+	#define LCD_E  12
+	#define LCD_D4 13
+	#define LCD_D5 14
+	#define LCD_D6 15
+	#define LCD_D7 16
+*/
+
+
+
+// Shared LCD stream object
+// Can be used with functions from stream.h once LCD is initialized
+extern STREAM* lcd;
+
+
+// --- Commands ---
+
+// Clear screen (reset)
+#define LCD_CLEAR 0b00000001
+// Move cursor to (0,0), unshift...
+#define LCD_HOME  0b00000010
+
+// Set mode: Increment + NoShift
+#define LCD_MODE_INC         0b00000110
+// Set mode: Increment + Shift
+#define LCD_MODE_INC_SHIFT   0b00000111
+
+// Set mode: Decrement + NoShift
+#define LCD_MODE_DEC         0b00000100
+// Set mode: Decrement + Shift
+#define LCD_MODE_DEC_SHIFT   0b00000101
+
+// Disable display (data remains untouched)
+#define LCD_DISABLE          0b00001000
+
+// Disable cursor
+#define LCD_CURSOR_NONE      0b00001100
+// Set cursor to still underscore
+#define LCD_CURSOR_BAR       0b00001110
+// Set cursor to blinking block
+#define LCD_CURSOR_BLINK     0b00001101
+// Set cursor to both of the above at once
+#define LCD_CURSOR_BOTH      (LCD_CURSOR_BAR | LCD_CURSOR_BLINK)
+
+// Move cursor
+#define LCD_MOVE_LEFT  0b00010000
+#define LCD_MOVE_RIGHT 0b00010100
+
+// Shift display
+#define LCD_SHIFT_LEFT  0b00011000
+#define LCD_SHIFT_RIGHT 0b00011100
+
+// Set iface to 5x7 font, 1-line
+#define LCD_IFACE_4BIT_1LINE 0b00100000
+#define LCD_IFACE_8BIT_1LINE 0b00110000
+// Set iface to 5x7 font, 2-line
+#define LCD_IFACE_4BIT_2LINE 0b00101000
+#define LCD_IFACE_8BIT_2LINE 0b00111000
+
+
+/** Initialize the display */
+void lcd_init();
+
+/** Write an instruction byte */
+void lcd_command(uint8_t bb);
+
+/** Write a data byte */
+void lcd_write(uint8_t bb);
+
+/** Read BF & Address */
+uint8_t lcd_read_bf_addr();
+
+/** Read CGRAM or DDRAM */
+uint8_t lcd_read();
+
+/** Send a string to LCD */
+void lcd_puts(char* str_p);
+
+/** Send a string to LCD from program memory */
+void lcd_puts_P(const char* str_p);
+
+/** Sedn a char to LCD */
+void lcd_putc(const char c);
+
+/** Show string at X, Y */
+#define lcd_puts_xy(x, y, str_p) do { lcd_xy((x), (y)); lcd_puts((str_p)); } while(0)
+
+/** Show string at X, Y */
+#define lcd_puts_xy_P(x, y, str_p) do { lcd_xy((x), (y)); lcd_puts_P((str_p)); } while(0)
+
+/** Show char at X, Y */
+#define lcd_putc_xy(x, y, c) do { lcd_xy((x), (y)); lcd_putc((c)); } while(0)
+
+/** Set cursor position */
+void lcd_xy(const uint8_t x, const uint8_t y);
+
+/** Set LCD cursor. If not enabled, only remember it. */
+#define CURSOR_NONE  0b00
+#define CURSOR_BAR   0b10
+#define CURSOR_BLINK 0b01
+#define CURSOR_BOTH  0b11
+void lcd_cursor(uint8_t type);
+
+/** Display display (preserving cursor) */
+void lcd_disable();
+
+/** Enable display (restoring cursor) */
+void lcd_enable();
+
+/** Go home */
+void lcd_home();
+
+/** Clear the screen */
+void lcd_clear();
+
+/** Define a glyph - 8 bytes, right 5 bits are used */
+void lcd_glyph(const uint8_t index, const uint8_t* array);
+
+/** Define a glyph that's in PROGMEM */
+void lcd_glyph_P(const uint8_t index, const uint8_t* array);
+
+/** Set address in CGRAM */
+void lcd_addr_cg(const uint8_t acg);
+
+/** Set address in DDRAM */
+void lcd_addr(const uint8_t add);

lib/porklib/nsdelay.h

@@ -0,0 +1,21 @@
+#pragma once
+
+//
+// Functions for precise delays (nanoseconds / cycles)
+//
+
+#include <avr/io.h>
+#include <util/delay_basic.h>
+#include <stdint.h>
+
+/* Convert nanoseconds to cycle count */
+#define ns2cycles(ns)  ( (ns) / (1000000000L / (signed long) F_CPU) )
+
+/** Wait c cycles */
+#define delay_c(c)  (((c) > 0) ? __builtin_avr_delay_cycles(c) :  __builtin_avr_delay_cycles(0))
+
+/** Wait n nanoseconds, plus c cycles  */
+#define delay_ns_c(ns, c)  delay_c(ns2cycles(ns) + (c))
+
+/** Wait n nanoseconds  */
+#define delay_ns(ns)  delay_c(ns2cycles(ns))

lib/porklib/onewire.c

@@ -0,0 +1,248 @@
+#include <avr/io.h>
+#include <util/delay.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "iopins.h"
+#include "onewire.h"
+
+
+/** Perform bus reset. Returns true if any device is connected */
+bool ow_reset(const uint8_t pin)
+{
+	as_output_n(pin);
+	pin_low_n(pin);
+	_delay_us(480);
+
+	as_input_pu_n(pin);
+	_delay_us(70);
+
+	const bool a = get_pin_n(pin);
+
+	_delay_us(410);
+
+	return a;
+}
+
+
+/** Send a single bit */
+void _ow_tx_bit(const uint8_t pin, const bool bit)
+{
+	as_output_n(pin);
+	pin_low_n(pin);
+
+	if (bit)
+	{
+		_delay_us(6);
+		as_input_pu_n(pin);
+		_delay_us(64);
+	}
+	else
+	{
+		_delay_us(60);
+		as_input_pu_n(pin);
+		_delay_us(10);
+	}
+}
+
+
+/** Send a single byte */
+void ow_send(const uint8_t pin, const uint8_t byte)
+{
+	for (uint8_t i = 0; i < 8; i++)
+	{
+		_ow_tx_bit(pin, (byte >> i) & 0x01);
+	}
+}
+
+
+/** Read a single bit */
+bool _ow_rx_bit(const uint8_t pin)
+{
+	as_output_n(pin);
+	pin_low_n(pin);
+	_delay_us(6);
+
+	as_input_pu_n(pin);
+	_delay_us(9);
+
+	const bool a = get_pin_n(pin);
+
+	_delay_us(55);
+
+	return a;
+}
+
+
+/** Read a single byte */
+uint8_t ow_read(const uint8_t pin)
+{
+	uint8_t byte = 0;
+
+	for (uint8_t i = 0; i < 8; i++)
+	{
+		byte = (byte >> 1) | (_ow_rx_bit(pin) << 7);
+	}
+
+	return byte;
+}
+
+
+/** Wait until the device is ready. Returns false on timeout */
+bool ow_wait_ready(const uint8_t pin)
+{
+	uint16_t timeout = 700;
+	as_input_pu_n(pin);
+
+	while (--timeout > 0)
+	{
+		if (is_high_n(pin)) return true;
+		_delay_ms(1);
+	}
+
+	return false;
+}
+
+
+/** Read bytes into an array */
+void ow_read_arr(const uint8_t pin, uint8_t* array, const uint8_t count)
+{
+	for (uint8_t i = 0; i < count; i++)
+	{
+		array[i] = ow_read(pin);
+	}
+}
+
+
+
+// ---------- CRC utils ----------
+
+/*
+ Dallas 1-wire CRC routines for Arduino with examples of usage.
+ The 16-bit routine is new.
+ The 8-bit routine is from http://github.com/paeaetech/paeae/tree/master/Libraries/ds2482/
+
+ Copyright (C) 2010 Kairama Inc
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+// Dallas 1-wire 16-bit CRC calculation. Developed from Maxim Application Note 27.
+
+/** Compute a CRC16 checksum */
+uint16_t crc16(uint8_t *data, uint8_t len)
+{
+	uint16_t crc = 0;
+
+	for (uint8_t i = 0; i < len; i++)
+	{
+		uint8_t inbyte = data[i];
+		for (uint8_t j = 0; j < 8; j++)
+		{
+			uint8_t mix = (crc ^ inbyte) & 0x01;
+			crc = crc >> 1;
+			if (mix)
+				crc = crc ^ 0xA001;
+
+			inbyte = inbyte >> 1;
+		}
+	}
+	return crc;
+}
+
+
+// The 1-Wire CRC scheme is described in Maxim Application Note 27:
+// "Understanding and Using Cyclic Redundancy Checks with Maxim iButton Products"
+
+/** Compute a CRC8 checksum */
+uint8_t crc8(uint8_t *addr, uint8_t len)
+{
+	uint8_t crc = 0;
+
+	for (uint8_t i = 0; i < len; i++)
+	{
+		uint8_t inbyte = addr[i];
+		for (uint8_t j = 0; j < 8; j++)
+		{
+			uint8_t mix = (crc ^ inbyte) & 0x01;
+			crc >>= 1;
+			if (mix)
+				crc ^= 0x8C;
+
+			inbyte >>= 1;
+		}
+	}
+
+	return crc;
+}
+
+
+// --- utils for DS1820 ---
+
+
+/** Read temperature in 0.0625°C, or TEMP_ERROR on error */
+int16_t ds1820_read_temp(uint8_t pin)
+{
+	ow_send(pin, READ_SCRATCHPAD);
+	uint8_t bytes[9];
+	ow_read_arr(pin, bytes, 9);
+
+	uint8_t crc = crc8(bytes, 8);
+	if (crc != bytes[8])
+	{
+		return TEMP_ERROR;
+	}
+	else
+	{
+		int16_t a = ((bytes[1] << 8) | bytes[0]) >> 1;
+		a = a << 4;
+		a += (16 - bytes[6]) & 0x0F;
+		a -= 0x04;
+
+		return a;
+	}
+}
+
+/** Read temperature in 0.1°C, or TEMP_ERROR on error */
+int16_t ds1820_read_temp_c(uint8_t pin)
+{
+	int32_t temp = ds1820_read_temp(pin);
+
+	if (temp == TEMP_ERROR)
+		return TEMP_ERROR;
+
+	temp *= 625;
+	uint16_t rem = temp % 1000;
+	temp /= 1000;
+	if (rem >= 500) temp++;
+
+	return (int16_t) temp;
+}
+
+
+bool ds1820_single_measure(uint8_t pin)
+{
+	ow_reset(pin);
+	ow_send(pin, SKIP_ROM);
+	ow_send(pin, CONVERT_T);
+
+	if (!ow_wait_ready(pin))
+	{
+		return false;
+	}
+
+	ow_reset(pin);
+	ow_send(pin, SKIP_ROM);
+
+	return true;
+}

lib/porklib/onewire.h

@@ -0,0 +1,58 @@
+#pragma once
+
+//
+// Utils for Dallas OneWire bus (DS1820 etc)
+//
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#define SKIP_ROM  0xCC
+#define CONVERT_T 0x44
+#define READ_SCRATCHPAD 0xBE
+
+/** Perform bus reset. Returns true if any device is connected */
+bool ow_reset(const uint8_t pin);
+
+/** Send a single byte */
+void ow_send(const uint8_t pin, const uint8_t byte);
+
+/** Read a single byte */
+uint8_t ow_read(const uint8_t pin);
+
+/** Wait until the device is ready. Returns false on timeout */
+bool ow_wait_ready(const uint8_t pin);
+
+/** Read bytes into an array */
+void ow_read_arr(const uint8_t pin, uint8_t* array, const uint8_t count);
+
+/** Compute a CRC16 checksum */
+uint16_t crc16(uint8_t *data, uint8_t len);
+
+/** Compute a CRC8 checksum */
+uint8_t crc8(uint8_t *addr, uint8_t len);
+
+// --- utils for DS1820 ---
+
+#define TEMP_ERROR -32768
+
+/**
+ * Read temperature in 0.0625°C, or TEMP_ERROR on error
+ * Use this where you'd normally use READ_SCRATCHPAD
+ */
+int16_t ds1820_read_temp(uint8_t pin);
+
+
+/**
+ * Read temperature in 0.1°C, or TEMP_ERROR on error
+ * Use this where you'd normally use READ_SCRATCHPAD
+ */
+int16_t ds1820_read_temp_c(uint8_t pin);
+
+/**
+ * Perform a temperature measurement with single DS1820 device on the line
+ * Can be followed by a call to read temperature (READ_SCRATCHPAD).
+ *
+ * Returns false on failure (device not connected)
+ */
+bool ds1820_single_measure(uint8_t pin);

lib/porklib/sd.c

@@ -0,0 +1,202 @@
+#include <avr/io.h>
+#include <util/delay.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "iopins.h"
+#include "spi.h"
+#include "sd.h"
+
+#define SD_RESET 0x40 // used to make card enter SPI mode
+#define SD_GET_STATUS 0x41 // used to check if card left IDLE - should return 0
+#define SD_SET_BLOCKLEN 0x50 // used to check if card left IDLE - should return 0
+#define SD_READ_BLOCK 0x51 // read single block
+#define SD_WRITE_BLOCK 0x58 // write single block
+
+
+bool sd_inited = false;
+
+bool sd_init()
+{
+	if (sd_inited) return true;
+	sd_inited = true;
+
+	uint8_t i;
+	spi_init();
+
+	spi_ss_disable(); // needed for init sequence, first command will enable it again
+
+	// idle for 10 bytes / 80 clocks
+	for (i = 0; i < 10; i++)
+	{
+		spi_write(0xFF);
+	}
+
+
+	// Send "Go to SPI mode" command, which should return "1"
+	for (i = 0; i < 100 && sd_command(SD_RESET, 0) != 1; i++)
+		_delay_ms(10);
+
+	if (i == 100)
+		return false; // timeout
+
+
+	// CMD1 until card comes out of "idle" mode
+	for (i = 0; i < 100 && sd_command(SD_GET_STATUS, 0) != 0; i++)
+		_delay_ms(10);
+
+	if (i == 100)
+		return false; // timeout
+
+
+	// f_cpu/8 speed (-> 2 MHz)
+	SPSR |= _BV(SPI2X);
+	SPCR &= 0xFC | _BV(SPR0);
+
+	// Set block size to 512 bytes (SD card default)
+	sd_command(SD_SET_BLOCKLEN, 512);
+
+	return true;
+}
+
+
+uint8_t sd_command(const uint8_t cmd, const uint32_t arg)
+{
+	spi_ss_enable();
+
+	spi_write(cmd);
+	spi_write(arg >> 24);
+	spi_write(arg >> 16);
+	spi_write(arg >> 8);
+	spi_write(arg);
+	spi_write(0x95); // CRC for the "init" command, later is ignored
+
+	// Send 8 bytes of 0xFF
+	// SD card replies with non-0xFF once it's done processing the command
+	uint8_t i, tmp, ret = 0xFF;
+	for (i = 0; i < 8; i++)
+	{
+		tmp = spi_write(0xFF);
+		if (tmp != 0xFF)
+			ret = tmp;
+	}
+
+	spi_ss_disable();
+
+	return ret;
+}
+
+
+bool sd_read(const uint32_t sector, const uint16_t read_at, uint8_t * buffer, const uint16_t write_at, const uint16_t len)
+{
+	if (read_at + len > 512) return false;
+
+	uint16_t i;
+
+	spi_ss_enable();
+	spi_write(SD_READ_BLOCK);
+	spi_write(sector >> 15); // sector * 512 >> 24
+	spi_write(sector >> 7);  // sector * 512 >> 16
+	spi_write(sector << 1);  // sector * 512 >> 8
+	spi_write(0);            // sector * 512
+	spi_write(0xFF);
+
+	// wait for 0 (ready)
+	for (i = 0; i < 100 && spi_write(0xFF) != 0x00; i++);
+	if (i == 100)
+	{
+		spi_ss_disable();
+		return false; // timeout
+	}
+
+
+	// wait for 0xFE (data start)
+	for (i = 0; i < 100 && spi_write(0xFF) != 0xFE; i++);
+	if (i == 100)
+	{
+		spi_ss_disable();
+		return false; // timeout
+	}
+
+	// skip "offset" bytes
+	for (i = 0; i < read_at; i++)
+		spi_write(0xFF);
+
+	// read "len" bytes
+	for (i = write_at; i < write_at + len; i++)
+		buffer[i] = spi_write(0xFF);
+
+	// skip remaining bytes in the sector
+	for (i = read_at + len; i < 512; i++)
+		spi_write(0xFF);
+
+	// skip checksum
+	spi_write(0xFF);
+	spi_write(0xFF);
+
+	spi_ss_disable();
+
+	return true;
+}
+
+
+
+bool sd_write(const uint32_t sector, const uint8_t * buffer512)
+{
+	uint16_t i;
+
+	spi_ss_enable();
+
+	spi_write(SD_WRITE_BLOCK);
+	spi_write(sector >> 15); // sector * 512 >> 24
+	spi_write(sector >> 7);  // sector * 512 >> 16
+	spi_write(sector << 1);  // sector * 512 >> 8
+	spi_write(0);            // sector * 512
+	spi_write(0xFF);
+
+	// wait for 0 (ready)
+	for (i = 0; i < 100 && spi_write(0xFF) != 0x00; i++);
+	if (i == 100)
+	{
+		spi_ss_disable();
+		return false; // timeout
+	}
+
+	// Start of data
+	spi_write(0xFE);
+
+	// Data
+	for (i = 0; i < 512; i++)
+	{
+		spi_write(buffer512[i]);
+	}
+
+	// Fake CRC
+	spi_write(0xFF);
+	spi_write(0xFF);
+
+	// Should contain flag that data was accepted
+	uint8_t resp = spi_write(0xFF);
+
+	if ((resp & 0x0F) != 0x05)
+	{
+		// Data not accepted
+		spi_ss_disable();
+		return false;
+	}
+	else
+	{
+		// Data accepted, wait for write complete
+		for (i = 0; i < 0xFFFF && spi_write(0xFF) == 0x00; i++);
+		if (i == 0xFFFF)
+		{
+			spi_ss_disable();
+			return false; // timeout
+		}
+	}
+
+	spi_write(0xFF); // 8 clocks
+	spi_ss_disable();
+
+	return true;
+}

lib/porklib/sd.h

@@ -0,0 +1,53 @@
+#pragma once
+
+//
+// SD card low-level I/O utilities
+//
+// Inspired by:
+// http://www.avrfreaks.net/forum/tutc-simple-fat-and-sd-tutorial
+//
+
+#include <avr/io.h>
+#include <avr/pgmspace.h>
+#include <util/delay.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "iopins.h"
+#include "spi.h"
+
+/** Init SD card on SPI */
+bool sd_init();
+
+
+/**
+ * Send a command to the SD card
+ *
+ * @param cmd command to send
+ * @param arg command argument
+ * @return return value on success, 0xFF if nothing received back.
+ */
+uint8_t sd_command(uint8_t cmd, uint32_t arg);
+
+
+/**
+ * Read from a sector into a buffer memory structure.
+ *
+ * @param sector   sector to read (512 bytes long each)
+ * @param read_at  offset within the sector
+ * @param buffer   target buffer
+ * @param write_at target starting address
+ * @param len      number of bytes to read
+ * @return true on success
+ */
+bool sd_read(uint32_t sector, uint16_t read_at, uint8_t * buffer, uint16_t write_at, uint16_t len);
+
+
+/**
+ * Write bytes from a buffer into a sector.
+ *
+ * @param sector    sector to write (512 bytes long each)
+ * @param buffer512 source buffer
+ * @return true on success
+ */
+bool sd_write(uint32_t sector, const uint8_t * buffer512);

lib/porklib/sd_blockdev.c

@@ -0,0 +1,184 @@
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "sd_blockdev.h"
+#include "sd.h"
+
+// helpers
+void load_sector(const uint32_t addr);
+void store_sector();
+void handle_cursor_ov();
+
+// blockdev methods
+void dev_load(void* dest, const uint16_t len);
+void dev_store(const void* src, const uint16_t len);
+uint8_t dev_read();
+void dev_write(const uint8_t b);
+void dev_seek(const uint32_t addr);
+void dev_rseek(const int16_t offset);
+void dev_flush();
+
+
+/** Sector buffer */
+uint8_t buff[512];
+
+/** Address of the buffered sector */
+uint32_t buff_addr;
+
+/** Buffer needs to be flushed before next read */
+bool buff_dirty = false;
+
+/** Buffer holds a valid sector */
+bool buff_valid = false;
+
+/** seek cursor */
+uint32_t cursor_sec;
+uint16_t cursor_offs;
+
+
+/** Flush the buffer, if it's dirty */
+void dev_flush()
+{
+	if (buff_dirty)
+	{
+		store_sector();
+		buff_dirty = false;
+	}
+}
+
+
+void load_sector(const uint32_t addr)
+{
+	// do not load if already loaded
+	if (buff_valid && buff_addr == addr)
+	{
+		return;
+	}
+
+	dev_flush();
+
+	// read entire sector
+	sd_read(addr, 0, buff, 0, 512);
+	buff_valid = true;
+	buff_addr = addr;
+}
+
+
+void store_sector()
+{
+	// Do not store if not laoded.
+	if (!buff_dirty) return;
+	if (!buff_valid) return;
+
+	sd_write(buff_addr, buff);
+}
+
+
+/**
+ * Handle cursor overflow.
+ * MUST ABSOLUTELY NOT load/store buffer or change buffer addr!
+*/
+inline void handle_cursor_ov()
+{
+	if (cursor_offs >= 512)
+	{
+		cursor_sec++;
+		cursor_offs = 0;
+	}
+}
+
+
+
+void dev_write(const uint8_t b)
+{
+	load_sector(cursor_sec);
+
+	// dirty only if changed
+	if (buff[cursor_offs] != b)
+	{
+		buff[cursor_offs++] = b;
+		buff_dirty = true;
+	}
+	else
+	{
+		cursor_offs++;
+	}
+
+	handle_cursor_ov();
+}
+
+
+uint8_t dev_read()
+{
+	load_sector(cursor_sec);
+	const uint8_t b = buff[cursor_offs++];
+
+	handle_cursor_ov();
+
+	return b;
+}
+
+
+void dev_load(void* dest, const uint16_t len)
+{
+	for (uint16_t a = 0; a < len; a++)
+	{
+		*((uint8_t*)dest++) = dev_read();
+	}
+}
+
+
+void dev_store(const void* src, const uint16_t len)
+{
+	for (uint16_t a = 0; a < len; a++)
+	{
+		dev_write(*((uint8_t*)src++));
+	}
+}
+
+
+void dev_seek(const uint32_t addr)
+{
+	// compute sector and offset counters
+	cursor_sec = addr >> 9;
+	cursor_offs = addr & 0x1FF;
+}
+
+
+void dev_rseek(const int16_t offset)
+{
+	// add WITHIN the same sector
+	if (offset > 0 && cursor_offs + offset < 512)
+	{
+		cursor_offs += offset;
+		return;
+	}
+
+	// subtract WITHIN the same sector
+	if (offset < 0 && ((uint16_t)(-offset) <= cursor_offs))
+	{
+		cursor_offs += offset;
+		return;
+	}
+
+	// abs addr change
+	dev_seek(((cursor_sec << 9) + cursor_offs) + offset);
+}
+
+
+/** Init SD card block device */
+bool sdb_init(BLOCKDEV* dev)
+{
+	if (!sd_init()) return false;
+
+	dev->load = &dev_load;
+	dev->store = &dev_store;
+	dev->read = &dev_read;
+	dev->write = &dev_write;
+	dev->seek = &dev_seek;
+	dev->rseek = &dev_rseek;
+	dev->flush = &dev_flush;
+
+	return true;
+}
+

lib/porklib/sd_blockdev.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include "blockdev.h"
+#include <stdbool.h>
+
+/** Initialize the SD card block device */
+bool sdb_init(BLOCKDEV* dev);

lib/porklib/sd_fat.c

@@ -0,0 +1,67 @@
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "sd_blockdev.h"
+#include "sd_fat.h"
+#include "fat16.h"
+
+FAT16 _fat;
+BLOCKDEV _dev;
+
+
+static STREAM _s;
+STREAM* sdf_stream = &_s;
+
+FFILE* stream_file;
+bool stream_active = false;
+
+void stream_tx(uint8_t b)
+{
+	if (!stream_active) return;
+	ff_write(stream_file, &b, 1);
+}
+
+
+uint8_t stream_rx()
+{
+	if (!stream_active) return 0;
+
+	uint8_t b;
+	ff_read(stream_file, &b, 1);
+	return b;
+}
+
+void sdf_open_stream(FFILE* file)
+{
+	stream_active = true;
+	stream_file = file;
+}
+
+
+bool sdfat_inited = false;
+
+bool sdf_init()
+{
+	if (sdfat_inited) return true;
+	sdfat_inited = true;
+
+	if (!sdb_init(&_dev)) return false;
+	if (!ff_init(&_dev, &_fat)) return false;
+
+	sdf_stream->rx = &stream_rx;
+	sdf_stream->tx = &stream_tx;
+
+	return true;
+}
+
+
+void sdf_root(FFILE* file)
+{
+	ff_root(&_fat, file);
+}
+
+
+void sdf_disk_label(char* str)
+{
+	ff_disk_label(&_fat, str);
+}

lib/porklib/sd_fat.h

@@ -0,0 +1,32 @@
+#pragma once
+
+//
+// FAT-on-SD helpers.
+//
+// This can be used for convenience, as it does all the init for you
+// and hides the implementation. All regular ff_* functions will work on the FFILE.
+//
+
+#include <stdint.h>
+
+#include "fat16.h"
+#include "stream.h"
+
+/** Initialize FAT16 filesystem on a SPI-connected SD card */
+bool sdf_init();
+
+/** Get first file of the root folder. */
+void sdf_root(FFILE* file);
+
+/** Get a disk label. Str should have 12 chars. */
+void sdf_disk_label(char* str);
+
+extern STREAM* sdf_stream;
+
+/**
+ * Open a stream for a file. There can be only one stream at a time.
+ *
+ * The stream will operate at the current file's cursor, just like
+ * ff_read and ff_write.
+*/
+void sdf_open_stream(FFILE* file);

lib/porklib/sipo_pwm.c

@@ -0,0 +1,83 @@
+#include <avr/io.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "sipo_pwm.h"
+#include "iopins.h"
+#include "sipo_pwm_config.h"
+
+
+/* -------- SIPO PWM MODULE ---------- */
+
+/** Buffer for sending bits to SIPO */
+bool _buff[SPWM_CHANNELS];
+
+uint8_t spwm_levels[SPWM_CHANNELS];
+
+
+/** Send _buff to SIPO */
+void _send_buffer()
+{
+	for (int8_t i = SPWM_CHANNELS - 1; i >= 0; i--)
+	{
+		#if (SPWM_INVERT)
+		set_pin(SPWM_DATA, !_buff[i]); /* Common anode */
+		#else
+		set_pin(SPWM_DATA, _buff[i]);  /* Common cathode */
+		#endif
+
+		// send a CLK pulse
+		pin_high(SPWM_CLK);
+		pin_low(SPWM_CLK);
+	}
+
+	// send a STR pulse
+	pin_high(SPWM_STR);
+	pin_low(SPWM_STR);
+}
+
+
+void spwm_init()
+{
+	// Pin directions
+	as_output(SPWM_CLK);
+	as_output(SPWM_STR);
+	as_output(SPWM_DATA);
+
+	// Initial states
+	pin_low(SPWM_CLK);
+	pin_low(SPWM_STR);
+}
+
+
+/**
+ * Display PWM channels.
+ * This could be called in a Timer ISR.
+ */
+void spwm_send()
+{
+	// Set all bits to 1 (if their PWM level is 0, set to 0)
+	for (uint8_t bit = 0; bit < SPWM_CHANNELS; bit++)
+	{
+		_buff[bit] = (bool) spwm_levels[bit];
+	}
+
+	// Show initial state
+	_send_buffer();
+
+	// For each PWM level...
+	for (uint16_t pwm = 0; pwm < SPWM_COLOR_DEPTH; pwm++)
+	{
+		// Turn OFF bits that are below the level
+		for (uint8_t bit = 0; bit < SPWM_CHANNELS; bit++)
+		{
+			if (spwm_levels[bit] < pwm)
+			{
+				_buff[bit] = 0;
+			}
+		}
+
+		// And show...
+		_send_buffer();
+	}
+}

lib/porklib/sipo_pwm.h

@@ -0,0 +1,49 @@
+#pragma once
+
+// --- SIPO PWM Module ---
+//
+// SIPO = shift register with paralel output.
+//
+// This module lets you use SIPO outputs as a "software PWM".
+//
+// Tested to work on 74hc4094 and 74hc595
+
+#include <stdint.h>
+
+// Your file with configs
+#include "sipo_pwm_config.h"
+/*
+	// --- PWM pin aliases ---
+	
+	// Store signal
+	#define SPWM_STR  D2
+	// Shift/clock signal
+	#define SPWM_CLK  D3
+	// Data signal
+	#define SPWM_DATA D4
+	
+	// --- Other settings ---
+	
+	// Number of PWM levels (color depth)
+	#define SPWM_COLOR_DEPTH 256
+	
+	// Number of SIPO channels
+	#define SPWM_CHANNELS 24
+	
+	// Invert outputs (for Common Anode LEDs)
+	#define SPWM_INVERT 1
+*/
+
+
+// Array for setting PWM levels (PWM_CHANNELS-long)
+extern uint8_t spwm_levels[SPWM_CHANNELS];
+
+
+/** Configure output pins etc */
+void spwm_init();
+
+
+/** Perform one PWM cycle.
+ * This should be called in a Timer ISR or a loop.
+ */
+void spwm_send();

lib/porklib/sonar.c

@@ -0,0 +1,168 @@
+#include <avr/io.h>
+#include <util/delay.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "iopins.h"
+#include "sonar.h"
+
+// Currently measured sonar
+static sonar_t* _so;
+
+// Flag that measurement is in progress
+volatile bool sonar_busy;
+
+// Result of last measurement, in millimeters
+volatile int16_t sonar_result;
+
+
+void _sonar_init_do(sonar_t* so, PORT_P port, uint8_t ntx, PORT_P pin, uint8_t nrx)
+{
+	so->port = port;
+	so->ntx = ntx;
+	so->pin = pin;
+	so->nrx = nrx;
+
+	switch ((const uint16_t) pin)
+	{
+		case ((const uint16_t) &PINB):
+			so->bank = 0;
+			break;
+
+		case ((const uint16_t) &PINC):
+			so->bank = 1;
+			break;
+
+		case ((const uint16_t) &PIND):
+			so->bank = 2;
+			break;
+	}
+}
+
+
+/**
+ * Start sonar measurement
+ * Interrupts must be enabled
+ * TIMER 1 will be used for the async measurement
+ * Timer 1 overflow and Pin Change interrupts must invoke Sonar handlers.
+ */
+bool sonar_start(sonar_t* so)
+{
+	if (sonar_busy) return false;
+
+	_so = so;
+
+	sonar_busy = true;
+
+	// make sure the timer is stopped (set clock to NONE)
+	TCCR1B = 0;
+
+	// Timer overflow interrupt enable
+	// We'll stop measuring on overflow
+	sbi(TIMSK1, TOIE1);
+
+	// Clear the timer value
+	TCNT1 = 0;
+
+	// Set up pin change interrupt mask for the RX pin
+	switch (so->bank)
+	{
+		case 0:
+			sbi(PCMSK0, so->nrx);
+			break;
+
+		case 1:
+			sbi(PCMSK1, so->nrx);
+			break;
+
+		case 2:
+			sbi(PCMSK2, so->nrx);
+			break;
+	}
+
+	// send positive pulse
+	sbi_p(so->port, so->ntx);
+	_delay_us(_SNR_TRIG_TIME);
+	cbi_p(so->port, so->ntx);
+
+	// Wait for start of response
+	while (bit_is_low_p(so->pin, so->nrx));
+
+	// Set timer clock source: F_CPU / 8 (0.5 us resolution)
+	TCCR1B = (0b010 << CS10);
+
+	// Enable pin change interrupt
+	sbi(PCICR, so->bank);
+
+	return true;
+}
+
+
+/** Stop the timer */
+void _sonar_stop()
+{
+	// stop timer
+	TCCR1B = 0;
+
+	// Disable RX pin interrupt mask
+	switch (_so->bank)
+	{
+		case 0:
+			PCMSK0 &= ~(1 << (_so->nrx));
+			break;
+
+		case 1:
+			PCMSK1 &= ~(1 << (_so->nrx));
+			break;
+
+		case 2:
+			PCMSK2 &= ~(1 << (_so->nrx));
+			break;
+	}
+
+	// Disable timer1 overflow interrupt
+	cbi(TIMSK1, TOIE1);
+
+	sonar_busy = false;
+}
+
+
+/** Handle TIMER1_OVF (returns true if consumed) */
+inline bool sonar_handle_t1ovf()
+{
+	if (!sonar_busy) return false; // nothing
+
+	sonar_result = -1;
+	_sonar_stop();
+
+	return true;
+}
+
+
+/** Handle pin change interrupt (returns true if consumed) */
+inline bool sonar_handle_pci()
+{
+	if (!sonar_busy)
+	{
+		return false; // nothing
+	}
+
+	if (bit_is_high_p(_so->pin, _so->nrx))
+	{
+		// rx is high, not our pin change event
+		return false;
+	}
+
+	uint64_t x = TCNT1;
+	x /= _SNR_DIV_CONST;
+	x *= 100000000L;
+	x /= F_CPU;
+	sonar_result = (int16_t) x;
+
+	// no obstacle
+	if (sonar_result > _SNR_MAX_DIST) sonar_result = -1;
+
+	_sonar_stop();
+
+	return true;
+}

lib/porklib/sonar.h

@@ -0,0 +1,67 @@
+#pragma once
+
+//
+// Utilities for working with the HC-SR04 ultrasonic sensor
+// Can be easily modified to work with other similar modules
+//
+// It's required that you call the sonar_handle_* functions from your ISRs
+// See example program for more info.
+//
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "iopins.h"
+
+// Calib constant for the module
+// CM = uS / _DIV_CONST
+#define _SNR_DIV_CONST 58
+
+// Max module distance in MM
+#define _SNR_MAX_DIST 4000
+
+// Trigger time in uS
+#define _SNR_TRIG_TIME 10
+
+
+// Sonar data object
+typedef struct
+{
+	PORT_P port; // Tx PORT
+	uint8_t ntx; // Tx bit number
+	PORT_P pin;  // Rx PIN
+	uint8_t nrx; // Rx bit number
+	uint8_t bank; // Rx PCINT bank
+} sonar_t;
+
+
+extern volatile bool sonar_busy;
+extern volatile int16_t sonar_result;
+
+
+// Create a Sonar port
+// Args: sonar_t* so, Trig pin, Echo pin
+#define sonar_init(so, trig, echo) do { \
+	as_output(trig); \
+	as_input_pu(echo); \
+	_sonar_init_do(so, &_port(trig), _pn(trig), &_pin(echo), _pn(echo)); \
+} while(0)
+
+// private, in header because of the macro.
+void _sonar_init_do(sonar_t* so, PORT_P port, uint8_t ntx, PORT_P pin, uint8_t nrx);
+
+
+/**
+ * Start sonar measurement
+ * Interrupts must be enabled
+ * TIMER 1 will be used for the async measurement
+ */
+bool sonar_start(sonar_t* so);
+
+
+/** Handle TIMER1_OVF (returns true if consumed) */
+bool sonar_handle_t1ovf();
+
+
+/** Handle pin change interrupt (returns true if consumed) */
+bool sonar_handle_pci();

lib/porklib/spi.c

@@ -0,0 +1,35 @@
+#include <avr/io.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "iopins.h"
+#include "spi.h"
+
+bool spi_inited = false;
+
+/** Init SPI (for SD card communication) */
+void spi_init()
+{
+	if (spi_inited) return;
+	spi_inited = true;
+
+	// Pin configuration
+	as_output(PIN_SS);
+	as_output(PIN_MOSI);
+	as_output(PIN_SCK);
+	as_input_pu(PIN_MISO);
+
+	// Enable SPI, master, clock = F_CPU/128
+	SPCR = _BV(SPE) | _BV(MSTR) | _BV(SPR0) | _BV(SPR1);
+}
+
+
+/** Write a byte to SPI. Returns received byte. */
+uint8_t spi_write(uint8_t b)
+{
+	SPDR = b;
+	while (!(SPSR & _BV(SPIF)));
+
+	return SPDR;
+}
+

lib/porklib/spi.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <stdint.h>
+
+#include "iopins.h"
+
+#define PIN_MISO 12
+#define PIN_MOSI 11
+#define PIN_SCK 13
+#define PIN_SS 10
+
+/** Set SS to active state (LOW) */
+#define spi_ss_enable()  pin_low(PIN_SS)
+
+/** Set SS to disabled state (HIGH) */
+#define spi_ss_disable() pin_high(PIN_SS)
+
+
+/** Init SPI (for SD card communication) */
+void spi_init();
+
+
+/**
+ * Write / read a byte to SPI.
+ *
+ * @param ch the written byte
+ * @return received byte
+ */
+uint8_t spi_write(uint8_t b);
+

lib/porklib/stream.c

@@ -0,0 +1,246 @@
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "stream.h"
+#include "calc.h"
+
+
+static char tmpstr[16]; // buffer for number rendering
+
+
+void put_bytes(const STREAM *p, const uint8_t* str, const uint16_t len)
+{
+	for (uint16_t i = 0; i < len; i++)
+	{
+		p->tx(str[i]);
+	}
+}
+
+
+void put_str(const STREAM *p, const char *str)
+{
+	char c;
+	while ((c = *str++))
+	{
+		p->tx(c);
+	}
+}
+
+
+void put_str_P(const STREAM *p, const char* str)
+{
+	char c;
+	while ((c = pgm_read_byte(str++)))
+	{
+		p->tx(c);
+	}
+}
+
+
+static void _putnf(const STREAM *p, const uint8_t places);
+
+
+void put_c(const STREAM *p, const uint8_t c)
+{
+	p->tx(c);
+}
+
+/** Send signed int8 */
+void put_u8(const STREAM *p, const uint8_t num)
+{
+	utoa(num, tmpstr, 10);
+	put_str(p, tmpstr);
+}
+
+
+/** Send unsigned int8 */
+void put_i8(const STREAM *p, const int8_t num)
+{
+	itoa(num, tmpstr, 10);
+	put_str(p, tmpstr);
+}
+
+
+
+/** Send unsigned int */
+void put_u16(const STREAM *p, const uint16_t num)
+{
+	utoa(num, tmpstr, 10);
+	put_str(p, tmpstr);
+}
+
+
+/** Send signed int */
+void put_i16(const STREAM *p, const int16_t num)
+{
+	itoa(num, tmpstr, 10);
+	put_str(p, tmpstr);
+}
+
+
+/** Send unsigned long */
+void put_u32(const STREAM *p, const uint32_t num)
+{
+	ultoa(num, tmpstr, 10);
+	put_str(p, tmpstr);
+}
+
+
+/** Send signed long */
+void put_i32(const STREAM *p, const int32_t num)
+{
+	ltoa(num, tmpstr, 10);
+	put_str(p, tmpstr);
+}
+
+
+/** Print number as hex */
+void _print_hex(const STREAM *p, uint8_t* start, uint8_t bytes)
+{
+	for (; bytes > 0; bytes--)
+	{
+		uint8_t b = *(start + bytes - 1);
+
+		for (uint8_t j = 0; j < 2; j++)
+		{
+			uint8_t x = high_nibble(b);
+
+			b = b << 4;
+
+			if (x < 0xA)
+			{
+				p->tx('0' + x);
+			}
+			else
+			{
+				p->tx('A' + (x - 0xA));
+			}
+		}
+	}
+}
+
+
+/** Send unsigned int8 */
+void put_x8(const STREAM *p, const uint8_t num)
+{
+	_print_hex(p, (uint8_t*) &num, 1);
+}
+
+
+/** Send int as hex */
+void put_x16(const STREAM *p, const uint16_t num)
+{
+	_print_hex(p, (uint8_t*) &num, 2);
+}
+
+
+/** Send long as hex */
+void put_x32(const STREAM *p, const uint32_t num)
+{
+	_print_hex(p, (uint8_t*) &num, 4);
+}
+
+
+/** Send long long as hex */
+void put_x64(const STREAM *p, const uint64_t num)
+{
+	_print_hex(p, (uint8_t*) &num, 8);
+}
+
+
+
+// float variant doesn't make sense for 8-bit int
+
+/** Send unsigned int as float */
+void put_u16f(const STREAM *p, const uint16_t num, const uint8_t places)
+{
+	utoa(num, tmpstr, 10);
+	_putnf(p, places);
+}
+
+
+/** Send signed int as float */
+void put_i16f(const STREAM *p, const int16_t num, const uint8_t places)
+{
+	if (num < 0)
+	{
+		p->tx('-');
+		itoa(-num, tmpstr, 10);
+	}
+	else
+	{
+		itoa(num, tmpstr, 10);
+	}
+
+	_putnf(p, places);
+}
+
+
+/** Send unsigned long as float */
+void put_u32f(const STREAM *p, const uint32_t num, const uint8_t places)
+{
+	ultoa(num, tmpstr, 10);
+	_putnf(p, places);
+}
+
+
+/** Send signed long as float */
+void put_i32f(const STREAM *p, const int32_t num, const uint8_t places)
+{
+	if (num < 0)
+	{
+		p->tx('-');
+		ltoa(-num, tmpstr, 10);
+	}
+	else
+	{
+		ltoa(num, tmpstr, 10);
+	}
+
+	_putnf(p, places);
+}
+
+
+/** Print number in tmp string as float with given decimal point position */
+void _putnf(const STREAM *p, const uint8_t places)
+{
+	// measure text length
+	uint8_t len = 0;
+	while (tmpstr[len] != 0) len++;
+
+	int8_t at = len - places;
+
+	// print virtual zeros
+	if (at <= 0)
+	{
+		p->tx('0');
+		p->tx('.');
+		while (at <= -1)
+		{
+			p->tx('0');
+			at++;
+		}
+		at = -1;
+	}
+
+	// print the number
+	uint8_t i = 0;
+	while (i < len)
+	{
+		if (at-- == 0)
+		{
+			p->tx('.');
+		}
+
+		p->tx(tmpstr[i++]);
+	}
+}
+
+
+/** Print CR LF */
+void put_nl(const STREAM *p)
+{
+	p->tx(13);
+	p->tx(10);
+}

lib/porklib/stream.h

@@ -0,0 +1,106 @@
+#pragma once
+
+//
+// Streams -- in this library -- are instances of type STREAM.
+//
+// A stream can be used for receiving and sending bytes, generally
+// it's a pipe to a device.
+//
+// They are designed for printing numbers and strings, but can
+// also be used for general data transfer.
+//
+// Examples of streams:
+// "uart.h" -> declares global variable "uart" which is a pointer to the UART stream
+// "lcd.h" -> declares a global variable "lcd" (pointer to LCD scho stream)
+//
+// Streams help avoid code duplication, since the same functions can be used
+// to format and print data to different device types.
+//
+
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <avr/pgmspace.h>
+
+/** Stream structure */
+typedef struct
+{
+	void (*tx)(uint8_t b);
+	uint8_t (*rx)(void);
+} STREAM;
+
+
+/** Send bytes to stream */
+void put_bytes(const STREAM *p, const uint8_t* str, uint16_t len);
+
+
+/** Print string into a stream */
+void put_str(const STREAM *p, const char *str);
+
+
+/** Print a programspace string into a stream */
+void put_str_P(const STREAM *p, const char* str);
+
+/** Put a char/byte. Basically the same as p->tx() */
+void put_c(const STREAM *p, uint8_t c);
+
+/** Send signed int8 */
+void put_u8(const STREAM *p, uint8_t num);
+
+
+/** Send unsigned int8 */
+void put_i8(const STREAM *p, int8_t num);
+
+
+/** Send unsigned int */
+void put_u16(const STREAM *p, uint16_t num);
+
+
+/** Send signed int */
+void put_i16(const STREAM *p, int16_t num);
+
+
+/** Send unsigned long */
+void put_u32(const STREAM *p, uint32_t num);
+
+
+/** Send signed long */
+void put_i32(const STREAM *p, int32_t num);
+
+
+/** Send unsigned int8 */
+void put_x8(const STREAM *p, uint8_t num);
+
+
+/** Send int as hex */
+void put_x16(const STREAM *p, uint16_t num);
+
+
+/** Send long as hex */
+void put_x32(const STREAM *p, uint32_t num);
+
+
+/** Send long long as hex */
+void put_x64(const STREAM *p, uint64_t num);
+
+
+// float variant doesn't make sense for 8-bit int
+
+/** Send unsigned int as float */
+void put_u16f(const STREAM *p, uint16_t num, uint8_t places);
+
+
+/** Send signed int as float */
+void put_i16f(const STREAM *p, int16_t num, uint8_t places);
+
+
+/** Send unsigned long as float */
+void put_u32f(const STREAM *p, uint32_t num, uint8_t places);
+
+
+/** Send signed long as float */
+void put_i32f(const STREAM *p, int32_t num, uint8_t places);
+
+
+/** Print CR LF */
+void put_nl(const STREAM *p);

lib/porklib/uart.c

@@ -0,0 +1,714 @@
+#include <avr/io.h>
+#include <avr/pgmspace.h>
+#include <util/delay.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#include "calc.h"
+#include "uart.h"
+#include "stream.h"
+
+// Shared stream instance
+static STREAM _uart_singleton;
+STREAM* uart = &_uart_singleton;
+
+
+void _uart_init_do(uint16_t ubrr)
+{
+	/*Set baud rate */
+	UBRR0H = (uint8_t)(ubrr >> 8);
+	UBRR0L = (uint8_t) ubrr;
+
+	// Enable Rx and Tx
+	UCSR0B = (1 << RXEN0) | (1 << TXEN0);
+
+	// 8-bit data, 1 stop bit
+	UCSR0C = (0b11 << UCSZ00);
+
+	_uart_singleton.tx = &uart_tx;
+	_uart_singleton.rx = &uart_rx;
+}
+
+
+/** Enable or disable RX ISR */
+void uart_isr_rx(bool yes)
+{
+	set_bit(UCSR0B, RXCIE0, yes);
+}
+
+
+/** Enable or disable TX ISR (1 byte is sent) */
+void uart_isr_tx(bool yes)
+{
+	set_bit(UCSR0B, TXCIE0, yes);
+}
+
+
+/** Enable or disable DRE ISR (all is sent) */
+void uart_isr_dre(bool yes)
+{
+	set_bit(UCSR0B, UDRIE0, yes);
+}
+
+
+/** Send byte over UART */
+void uart_tx(uint8_t data)
+{
+	// Wait for transmit buffer
+	while (!uart_tx_ready());
+	// send it
+	UDR0 = data;
+}
+
+
+/** Receive one byte over UART */
+uint8_t uart_rx()
+{
+	// Wait for data to be received
+	while (!uart_rx_ready());
+	// Get and return received data from buffer
+	return UDR0;
+}
+
+
+/** Send string over UART */
+void uart_puts(const char* str)
+{
+	while (*str)
+	{
+		uart_tx(*str++);
+	}
+}
+
+
+/** Send progmem string over UART */
+void uart_puts_P(const char* str)
+{
+	char c;
+	while ((c = pgm_read_byte(str++)))
+	{
+		uart_tx(c);
+	}
+}
+
+
+/** Clear receive buffer */
+void uart_flush()
+{
+	uint8_t dummy;
+	while (bit_is_high(UCSR0A, RXC0))
+	{
+		dummy = UDR0;
+	}
+}
+
+
+// ------------- VT100 extension --------------
+
+
+void _vt_apply_style();
+void _vt_reset_attribs_do();
+void _vt_style_do();
+void _vt_color_do();
+
+
+void vt_goto(uint8_t x, uint8_t y)
+{
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, y + 1); // one-based !
+	uart_tx(';');
+	put_u8(uart, x + 1);
+	uart_tx('H');
+}
+
+
+void vt_goto_x(uint8_t x)
+{
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, x + 1);
+	uart_tx('`');
+}
+
+
+void vt_goto_y(uint8_t y)
+{
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, y + 1);
+	uart_tx('d');
+}
+
+
+void vt_move(int8_t x, int8_t y)
+{
+	vt_move_x(x);
+	vt_move_y(y);
+}
+
+
+void vt_move_x(int8_t x)
+{
+	if (x < 0)
+	{
+		vt_left(-x);
+	}
+	else
+	{
+		vt_right(x);
+	}
+}
+
+
+void vt_move_y(int8_t y)
+{
+	if (y < 0)
+	{
+		vt_up(-y);
+	}
+	else
+	{
+		vt_down(y);
+	}
+}
+
+
+void vt_up(uint8_t y)
+{
+	if (y == 0) return;
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, y);
+	uart_tx('A');
+}
+
+
+void vt_down(uint8_t y)
+{
+	if (y == 0) return;
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, y);
+	uart_tx('B');
+}
+
+
+void vt_left(uint8_t x)
+{
+	if (x == 0) return;
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, x);
+	uart_tx('D');
+}
+
+
+void vt_right(uint8_t x)
+{
+	if (x == 0) return;
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, x);
+	uart_tx('C');
+}
+
+
+void vt_scroll(int8_t y)
+{
+	while (y < 0)
+	{
+		uart_tx(27);
+		uart_tx('D'); // up
+		y++;
+	}
+
+	while (y > 0)
+	{
+		uart_tx(27);
+		uart_tx('M'); // down
+		y--;
+	}
+}
+
+
+void vt_scroll_set(uint8_t from, uint8_t to)
+{
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, from);
+	uart_tx(';');
+	put_u8(uart, to);
+	uart_tx('r');
+}
+
+
+void vt_scroll_reset()
+{
+	uart_tx(27);
+	uart_tx('[');
+	uart_tx('r');
+}
+
+
+
+typedef struct
+{
+	uint8_t flags;
+	uint8_t fg;
+	uint8_t bg;
+} vt_style_t;
+
+vt_style_t saved_style;
+vt_style_t current_style;
+
+void vt_save()
+{
+	uart_puts_P(PSTR("\x1B[s"));
+
+	saved_style = current_style;
+}
+
+
+void vt_restore()
+{
+	uart_puts_P(PSTR("\x1B[u"));
+
+	current_style = saved_style;
+}
+
+
+/** Disable all text attributes (excluding color) */
+void vt_attr_reset()
+{
+	current_style.flags = 0;
+
+	_vt_reset_attribs_do();
+	_vt_apply_style();
+}
+
+
+/** Set color to white on black */
+void vt_color_reset()
+{
+	current_style.fg = VT_WHITE;
+	current_style.bg = VT_BLACK;
+
+	_vt_color_do();
+}
+
+
+/** Enable or disable a text attribute */
+void vt_attr(uint8_t attribute, bool on)
+{
+	// flags are powers of two
+	// so this can handle multiple OR'd flags
+	for (uint8_t c = 1; c <= VT_FAINT; c *= 2)
+	{
+		if (attribute & c)
+		{
+			if (on)
+			{
+				current_style.flags |= c;
+			}
+			else
+			{
+				current_style.flags &= ~c;
+			}
+		}
+	}
+
+	_vt_apply_style();
+}
+
+
+/** Send style and color commands */
+void _vt_apply_style()
+{
+	_vt_reset_attribs_do();
+	_vt_style_do();
+	_vt_color_do();
+}
+
+
+/** Set color 0..7 */
+void vt_color(uint8_t fg, uint8_t bg)
+{
+	current_style.fg = fg;
+	current_style.bg = bg;
+	_vt_color_do();
+}
+
+
+/** Set FG color 0..7 */
+void vt_color_fg(uint8_t fg)
+{
+	current_style.fg = fg;
+	_vt_color_do();
+}
+
+
+/** Set BG color 0..7 */
+void vt_color_bg(uint8_t bg)
+{
+	current_style.bg = bg;
+	_vt_color_do();
+}
+
+
+/** Send reset command */
+inline void _vt_reset_attribs_do()
+{
+	uart_puts_P(PSTR("\x1B[m")); // reset
+}
+
+
+/** Send commands for text attribs */
+void _vt_style_do()
+{
+	if (current_style.flags & VT_BOLD)
+	{
+		uart_puts_P(PSTR("\x1B[1m"));
+	}
+
+	if (current_style.flags & VT_FAINT)
+	{
+		uart_puts_P(PSTR("\x1B[2m"));
+	}
+
+	if (current_style.flags & VT_ITALIC)
+	{
+		uart_puts_P(PSTR("\x1B[3m"));
+	}
+
+	if (current_style.flags & VT_UNDERLINE)
+	{
+		uart_puts_P(PSTR("\x1B[4m"));
+	}
+
+	if (current_style.flags & VT_BLINK)
+	{
+		uart_puts_P(PSTR("\x1B[5m"));
+	}
+
+	if (current_style.flags & VT_REVERSE)
+	{
+		uart_puts_P(PSTR("\x1B[7m"));
+	}
+}
+
+
+/** Send commands for xolor */
+void _vt_color_do()
+{
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, 30 + current_style.fg);
+	uart_tx(';');
+	put_u8(uart, 40 + current_style.bg);
+	uart_tx('m');
+}
+
+
+/** Insert blank lines febore the current line */
+void vt_insert_lines(uint8_t count)
+{
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, count);
+	uart_tx('L');
+}
+
+
+/** Delete lines from the current line down */
+void vt_delete_lines(uint8_t count)
+{
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, count);
+	uart_tx('M');
+}
+
+
+/** Insert empty characters at cursor */
+void vt_insert_chars(uint8_t count)
+{
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, count);
+	uart_tx('@');
+}
+
+
+/** Delete characters at cursor */
+void vt_delete_chars(uint8_t count)
+{
+	uart_tx(27);
+	uart_tx('[');
+	put_u8(uart, count);
+	uart_tx('P');
+}
+
+
+void vt_clear()
+{
+	uart_puts_P(PSTR("\x1B[2J"));
+}
+
+
+void vt_erase_forth()
+{
+	uart_puts_P(PSTR("\x1B[K"));
+}
+
+
+void vt_erase_back()
+{
+	uart_puts_P(PSTR("\x1B[1K"));
+}
+
+
+void vt_erase_line()
+{
+	uart_puts_P(PSTR("\x1B[2K"));
+}
+
+
+void vt_erase_above()
+{
+	uart_puts_P(PSTR("\x1B[1J"));
+}
+
+void vt_erase_below()
+{
+	uart_puts_P(PSTR("\x1B[J"));
+}
+
+
+void vt_home()
+{
+	uart_puts_P(PSTR("\x1B[H"));
+}
+
+
+/** Initialize helper variables */
+void vt_init()
+{
+	vt_reset();
+}
+
+
+/** Reset state and clear screen */
+void vt_reset()
+{
+	// reset color and attributes
+	vt_color_reset();
+	vt_attr_reset();
+	vt_scroll_reset();
+
+	// clear screen
+	vt_clear();
+
+	// go to top left
+	vt_home();
+
+	// overwrite saved state
+	vt_save();
+}
+
+
+
+// Assigned keyhandler
+void (*_vt_kh)(uint8_t, bool) = NULL;
+
+/** Assign a key handler (later used with vt_handle_key) */
+void vt_set_key_handler(void (*handler)(uint8_t, bool))
+{
+	_vt_kh = handler;
+}
+
+
+// state machine states
+typedef enum
+{
+	GROUND = 0,
+	ESC = 1,
+	BR = 2,
+	O = 3,
+	WAITING_TILDE = 4
+} KSTATE;
+
+// code received before started to wait for a tilde
+uint8_t _before_wtilde;
+// current state
+KSTATE _kstate = GROUND;
+
+
+
+void _vt_kh_abort()
+{
+	switch (_kstate)
+	{
+		case ESC:
+			_vt_kh(VK_ESC, true);
+			break;
+
+		case BR:
+			_vt_kh(VK_ESC, true);
+			_vt_kh('[', false);
+			break;
+
+		case O:
+			_vt_kh(VK_ESC, true);
+			_vt_kh('O', false);
+			break;
+
+		case WAITING_TILDE:
+			_vt_kh(VK_ESC, true);
+			_vt_kh('[', false);
+			vt_handle_key(_before_wtilde);
+			break;
+
+		case GROUND:
+			// nop
+			break;
+	}
+
+	_kstate = GROUND;
+}
+
+
+/**
+ * Handle a key received over UART
+ * Takes care of multi-byte keys and translates them to special
+ * constants.
+ */
+void vt_handle_key(uint8_t c)
+{
+	if (_vt_kh == NULL) return;
+
+	switch (_kstate)
+	{
+		case GROUND:
+			switch (c)
+			{
+				case 27:
+					_kstate = ESC;
+					break;
+
+				case VK_ENTER:
+				case VK_TAB:
+				case VK_BACKSPACE:
+					_vt_kh(c, true);
+					return;
+
+				default:
+					_vt_kh(c, false);
+					return;
+			}
+
+			break;  // continue to next char
+
+		case ESC:
+			switch (c)
+			{
+				case '[':
+					_kstate = BR;
+					break; // continue to next char
+
+				case 'O':
+					_kstate = O;
+					break; // continue to next char
+
+				default:
+					// bad code
+					_vt_kh_abort();
+					vt_handle_key(c);
+					return;
+			}
+			break;
+
+		case BR:
+			switch (c)
+			{
+				// arrows
+				case 65:
+				case 66:
+				case 67:
+				case 68:
+					_vt_kh(c, true);
+					_kstate = GROUND;
+					return;
+
+				// ins del pgup pgdn
+				case 50:
+				case 51:
+				case 53:
+				case 54:
+					// wait for terminating tilde
+					_before_wtilde = c;
+					_kstate = WAITING_TILDE;
+					break; // continue to next char
+
+				// bad key
+				default:
+					_vt_kh_abort();
+					vt_handle_key(c);
+					return;
+			}
+			break;
+
+		case O:
+			switch (c)
+			{
+				// F keys
+				case 80:
+				case 81:
+				case 82:
+				case 83:
+				// home, end
+				case 72:
+				case 70:
+					_vt_kh(c, true);
+					_kstate = GROUND;
+					return;
+
+				// bad key
+				default:
+					_vt_kh_abort();
+					vt_handle_key(c);
+					return;
+			}
+
+		case WAITING_TILDE:
+			if (c != '~')
+			{
+				_vt_kh_abort();
+				vt_handle_key(c);
+				return;
+			}
+			else
+			{
+				_vt_kh(_before_wtilde, true);
+				_kstate = GROUND;
+				return;
+			}
+	}
+
+	// wait for next key
+	if (_kstate != GROUND)
+	{
+		_delay_ms(2);
+		if (!uart_rx_ready())
+		{
+			// abort receiving
+			_vt_kh_abort();
+
+		}
+		else
+		{
+			vt_handle_key(uart_rx());
+		}
+	}
+}

lib/porklib/uart.h

@@ -0,0 +1,253 @@
+#pragma once
+
+//
+// Utilities for UART communication.
+//
+// First, init uart with desired baud rate using uart_init(baud).
+// Then enable interrupts you want with uart_isr_XXX().
+//
+
+#include <avr/io.h>
+#include <avr/pgmspace.h>
+#include <util/delay.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "stream.h"
+
+// Shared UART stream object
+// Can be used with functions from stream.h once UART is initialized
+extern STREAM* uart;
+
+/** Init UART for given baudrate */
+void _uart_init_do(uint16_t ubrr); // internal, needed for the macro.
+#define uart_init(baud) _uart_init_do(F_CPU / 16 / (baud) - 1)
+
+/** Check if there's a byte in the RX register */
+#define uart_rx_ready() (0 != (UCSR0A & (1 << RXC0)))
+
+/** Check if transmission of everything is done */
+#define uart_tx_ready() (0 != (UCSR0A & (1 << UDRE0)))
+
+
+
+// Enable UART interrupts
+
+/** Enable or disable RX ISR */
+void uart_isr_rx(bool enable);
+
+/** Enable or disable TX ISR (1 byte is sent) */
+void uart_isr_tx(bool enable);
+
+/** Enable or disable DRE ISR (all is sent) */
+void uart_isr_dre(bool enable);
+
+
+
+// Basic IO
+
+/** Receive one byte over UART */
+uint8_t uart_rx();
+
+/** Send byte over UART */
+#define uart_putc(data) uart_tx((data))
+void uart_tx(uint8_t data);
+
+/** Clear receive buffer */
+void uart_flush();
+
+
+
+// Strings
+
+/** Send string over UART */
+void uart_puts(const char* str);
+
+/** Send progmem string over UART */
+void uart_puts_P(const char* str);
+
+
+
+//
+// ANSI / VT100 utilities for UART
+//
+// To use this, first call uart_init(baud) and vt_init()
+// To print stuff on the screen, use uart_puts() etc from uart.h
+//
+
+
+// INIT
+
+/** Initialize helper variables */
+void vt_init();
+
+/** Reset state and clear screen */
+void vt_reset();
+
+
+
+// CURSOR MOVE
+
+/** Move cursor to top left corner */
+void vt_home();
+
+/** Jump to a location on the screen */
+void vt_goto(uint8_t x, uint8_t y);
+
+/** Jump to given X, keep Y */
+void vt_goto_x(uint8_t x);
+
+/** Jump to given Y, keep X */
+void vt_goto_y(uint8_t y);
+
+/** Move cursor relative to current location */
+void vt_move(int8_t x, int8_t y);
+
+/** Move cursor horizontally */
+void vt_move_x(int8_t x);
+
+/** Move cursor vertically */
+void vt_move_y(int8_t y);
+
+/** Move cursor up y cells */
+void vt_up(uint8_t y);
+
+/** Move cursor down y cells */
+void vt_down(uint8_t y);
+
+/** Move cursor left x cells */
+void vt_left(uint8_t x);
+
+/** Move cursor right x cells */
+void vt_right(uint8_t x);
+
+
+
+// SCROLLING
+
+/** Scroll y lines down (like up/down, but moves window if needed) */
+void vt_scroll(int8_t down);
+
+/** Set scrolling region (lines) */
+void vt_scroll_set(uint8_t from, uint8_t to);
+
+
+/** Sets scrolling region to the entire screen. */
+void vt_scroll_reset();
+
+
+// COLOR
+
+#define VT_BLACK 0
+#define VT_RED 1
+#define VT_GREEN 2
+#define VT_YELLOW 3
+#define VT_BLUE 4
+#define VT_MAGENTA 5
+#define VT_CYAN 6
+#define VT_WHITE 7
+
+/** Set color 0..7 */
+void vt_color(uint8_t fg, uint8_t bg);
+
+/** Set FG color 0..7 */
+void vt_color_fg(uint8_t fg);
+
+/** Set BG color 0..7 */
+void vt_color_bg(uint8_t bg);
+
+/** Set color to white on black */
+void vt_color_reset();
+
+
+
+// STYLES
+
+#define VT_BOLD 1
+#define VT_UNDERLINE 2
+#define VT_BLINK 4
+#define VT_REVERSE 8
+#define VT_ITALIC 16
+#define VT_FAINT 32
+
+/** Enable or disable a text attribute */
+void vt_attr(uint8_t attribute, bool on);
+
+/** Disable all text attributes (excluding color) */
+void vt_attr_reset();
+
+
+
+// SAVE & RESTORE
+
+/** Save cursor position & text attributes */
+void vt_save();
+
+/** Restore cursor to saved values */
+void vt_restore();
+
+
+
+// MODIFY
+
+
+/** Insert blank lines febore the current line */
+void vt_insert_lines(uint8_t count);
+
+/** Delete lines from the current line down */
+void vt_delete_lines(uint8_t count);
+
+/** Insert empty characters at cursor */
+void vt_insert_chars(uint8_t count);
+
+/** Delete characters at cursor */
+void vt_delete_chars(uint8_t count);
+
+
+
+// ERASING
+
+/** Clear the screen */
+void vt_clear();
+
+/** Erase to the end of line */
+void vt_erase_forth();
+
+/** Erase line to cursor */
+void vt_erase_back();
+
+/** Erase entire line */
+void vt_erase_line();
+
+/** Erase screen below the line */
+void vt_erase_above();
+
+/** Erase screen above the line */
+void vt_erase_below();
+
+
+
+// KEY HANDLER
+
+// Special keys from key handler
+#define VK_LEFT   68
+#define VK_RIGHT  67
+#define VK_UP     65
+#define VK_DOWN   66
+#define VK_DELETE 51
+#define VK_INSERT 50
+#define VK_PGUP   53
+#define VK_PGDN   54
+#define VK_HOME   72
+#define VK_END    70
+#define VK_F1 80
+#define VK_F2 81
+#define VK_F3 82
+#define VK_F4 83
+#define VK_BACKSPACE  8
+#define VK_TAB        9
+#define VK_ENTER     13
+#define VK_ESC       27
+
+void vt_handle_key(uint8_t c);
+void vt_set_key_handler(void (*handler)(uint8_t, bool));

lib/porklib/wsrgb.c

@@ -0,0 +1,139 @@
+#include <avr/io.h>
+#include <util/delay.h>
+#include <stdint.h>
+
+#include "iopins.h"
+#include "nsdelay.h"
+
+#include "wsrgb.h"
+#include "color.h"
+#include "ws_config.h"
+
+
+/* Driver code for WS2812B */
+
+void ws_init()
+{
+	as_output(WS_PIN);
+}
+
+/** Wait long enough for the colors to show */
+void ws_show()
+{
+	delay_ns_c(WS_T_LATCH, 0);
+}
+
+/** Send one byte to the RGB strip */
+void ws_send_byte(const uint8_t bb)
+{
+	for (volatile int8_t i = 7; i >= 0; --i)
+	{
+		if ((bb) & (1 << i))
+		{
+			pin_high(WS_PIN);
+			delay_ns_c(WS_T_1H, -2);
+
+			pin_low(WS_PIN);
+			delay_ns_c(WS_T_1L, -10);
+		}
+		else
+		{
+			pin_high(WS_PIN);
+			delay_ns_c(WS_T_0H, -2);
+
+			pin_low(WS_PIN);
+			delay_ns_c(WS_T_0L, -10);
+		}
+	}
+}
+
+
+/** Send R,G,B color to the strip */
+void ws_send_rgb(const uint8_t r, const uint8_t g, const uint8_t b)
+{
+	ws_send_byte(g);
+	ws_send_byte(r);
+	ws_send_byte(b);
+}
+
+
+/** Send a RGB struct */
+void ws_send_xrgb(xrgb_t xrgb)
+{
+	ws_send_byte(xrgb.g);
+	ws_send_byte(xrgb.r);
+	ws_send_byte(xrgb.b);
+}
+
+
+/** Send color hex */
+void ws_send_rgb24(rgb24_t rgb)
+{
+	ws_send_byte(rgb24_g(rgb));
+	ws_send_byte(rgb24_r(rgb));
+	ws_send_byte(rgb24_b(rgb));
+}
+
+/** Send array of colors */
+void ws_send_xrgb_array(const xrgb_t rgbs[], const uint8_t length)
+{
+	for (uint8_t i = 0; i < length; i++)
+	{
+		const xrgb_t c = rgbs[i];
+		ws_send_byte(c.g);
+		ws_send_byte(c.r);
+		ws_send_byte(c.b);
+	}
+}
+
+/** Send array of colors */
+void ws_send_rgb24_array(const rgb24_t rgbs[], const uint8_t length)
+{
+	for (uint8_t i = 0; i < length; i++)
+	{
+		const rgb24_t c = rgbs[i];
+		ws_send_byte(rgb24_g(c));
+		ws_send_byte(rgb24_r(c));
+		ws_send_byte(rgb24_b(c));
+	}
+}
+
+//#define ws_send_rgb24_array(rgbs, length) __ws_send_array_proto((rgbs), (length), rgb24)
+
+// prototype for sending array. it's ugly, sorry.
+/*#define __ws_send_array_proto(rgbs, length, style) {                      \
+	for (uint8_t __rgb_sap_i = 0; __rgb_sap_i < length; __rgb_sap_i++) {            \
+		style ## _t __rgb_sap2 = (rgbs)[__rgb_sap_i];                               \
+		ws_send_ ## style(__rgb_sap2);                              \
+	}                                                                           \
+}*/
+
+
+// /** Send a 2D array to a zig-zag display */
+// #define ws_send_xrgb_array_zigzag(rgbs, width, height) {             \
+//  int8_t __rgb_sxaz_y, __rgb_sxaz_x;                                      \
+//  for(__rgb_sxaz_y = 0; __rgb_sxaz_y < (height); __rgb_sxaz_y ++) {           \
+//      for(__rgb_sxaz_x = 0; __rgb_sxaz_x < (width); __rgb_sxaz_x++) {     \
+//          ws_send_xrgb((rgbs)[__rgb_sxaz_y][__rgb_sxaz_x]);   \
+//      }                                                                   \
+//      __rgb_sxaz_y++;                                                     \
+//      for(__rgb_sxaz_x = (width) - 1; __rgb_sxaz_x >= 0; __rgb_sxaz_x--) {    \
+//          ws_send_xrgb((rgbs)[__rgb_sxaz_y][__rgb_sxaz_x]);   \
+//      }                                                                   \
+//  }                                                                       \
+// }
+
+
+// /* Send a linear array to a zig-zag display as a n*m board (row-by-row)
+// #define ws_send_xrgb_array_zigzag_linear(rgbs, width, height) {                  \
+//  int8_t __rgb_sxazl_x, __rgb_sxazl_y;                                                    \
+//  for(__rgb_sxazl_y = 0; __rgb_sxazl_y < (height); __rgb_sxazl_y++) {                 \
+//      for(__rgb_sxazl_x = 0; __rgb_sxazl_x < (width); __rgb_sxazl_x++) {                  \
+//          ws_send_xrgb((rgbs)[__rgb_sxazl_y * (width) + __rgb_sxazl_x]);  \
+//      }                                                                               \
+//      __rgb_sxazl_y++;                                                                    \
+//      for(__rgb_sxazl_x = width-1; __rgb_sxazl_x >=0; __rgb_sxazl_x--) {                  \
+//          ws_send_xrgb((rgbs)[__rgb_sxazl_y * (width) + __rgb_sxazl_x]);  \
+//      }                                                                               \
+//  }                                                                                   \
+// }

lib/porklib/wsrgb.h

@@ -0,0 +1,53 @@
+#pragma once
+
+//
+// Utils for driving a WS2812 RGB LED strips, and color manipulation in general.
+//
+// Timing is critical!
+//
+// Create a config file rgb_config.h next to your main.c
+//
+
+#include <stdint.h>
+
+#include "iopins.h"
+#include "color.h"
+
+// Your config file
+#include "ws_config.h"
+
+/*
+	#define WS_T_1H  700
+	#define WS_T_1L  150
+	#define WS_T_0H  150
+	#define WS_T_0L  700
+	#define WS_T_LATCH 7000
+	#define WS_PIN 2
+*/
+
+
+// --- functions for RGB strips ---
+
+/** Initialize OI */
+void ws_init();
+
+/** Wait long enough for the colors to show */
+void ws_show();
+
+/** Send one byte to the RGB strip */
+void ws_send_byte(const uint8_t bb);
+
+/** Send R,G,B color to the strip */
+void ws_send_rgb(const uint8_t r, const uint8_t g, const uint8_t b);
+
+/** Send a RGB struct */
+void ws_send_xrgb(xrgb_t xrgb);
+
+/** Send color hex */
+void ws_send_rgb24(rgb24_t rgb);
+
+/** Send array of colors */
+void ws_send_xrgb_array(const xrgb_t rgbs[], const uint8_t length);
+
+/** Send array of colors */
+void ws_send_rgb24_array(const rgb24_t rgbs[], const uint8_t length);

src/main.c

@@ -1,46 +1,130 @@
 #include "twi.h"
 #include "ssd1306.h"
 #include "sevenseg.h"
+#include "adc.h"
+#include "iopins.h"
+#include <avr/interrupt.h>
 
-void main() {
-    TWI_Init();
+const uint16_t adc_target16_acceptable = 900;
+const uint16_t adc_target16 = 972;
+//const uint8_t adc_target8 = 243;
 
+static bool g_pwm_on = false;
 
-    ssd1306_128x32_i2c_init();
-//    ssd1306_128x64_spi_init(-1, 0, 1);  // Use this line for nano pi (RST not used, 0=CE, gpio1=D/C)
-//    ssd1306_128x64_spi_init(3,4,5);     // Use this line for Atmega328p (3=RST, 4=CE, 5=D/C)
-//    ssd1306_128x64_spi_init(24, 0, 23); // Use this line for Raspberry  (gpio24=RST, 0=CE, gpio23=D/C)
-//    ssd1306_128x64_spi_init(22, 5, 21); // Use this line for ESP32 (VSPI)  (gpio22=RST, gpio5=CE for VSPI, gpio21=D/C)
-//    composite_video_128x64_mono_init(); // Use this line for ESP32 with Composite video support
+static volatile uint16_t tick_counter = 0;
+static volatile bool tick_counter_changed = false;
 
-    ssd1306_clearScreen();
+// Tick
+ISR(INT0_vect)
+{
+    tick_counter++;
+    tick_counter_changed = true;
+}
+
+static void init_isr() {
+    as_input(D2);
+
+    // using INT0 - arduino pin D2
+    EICRA = _BV(ISC01) | _BV(ISC00); // rising edge
+    EIMSK = _BV(INT0);
+}
 
-    //ssd1306_drawLine(0,0, ssd1306_displayWidth() -1, ssd1306_displayHeight() -1);
+static void init_pwm_out() {
+    // Output is OC0A
+    as_output(D5);
 
+    // initialize the timer
+    // Fast PWM mode, Output to OC0A
 
-    const uint8_t charw = 18;
-    const uint8_t spacing = 6;
-    const uint8_t barw=4;
+    // clock is 16MHz, presc /64, counting to 80 -> freq 3125Hz
+    // Duty cycle = appx. 60%
+
+    OCR0A = 80;
+    OCR0B = 46;
+    TCCR0A = _BV(WGM00) | _BV(WGM01);
+    TCCR0B = _BV(CS01) | _BV(CS00) | _BV(WGM02);
+}
+
+static void pwm_on() {
+    TCCR0A |= _BV(COM0B1);
+    g_pwm_on = true;
+}
+
+static void pwm_off() {
+    TCCR0A &= ~_BV(COM0B1);
+    g_pwm_on = false;
+}
+
+void main() {
+    TWI_Init();
+    adc_init();
+
+    init_pwm_out();
+
+    ssd1306_128x32_i2c_init();
+    ssd1306_clearScreen();
 
     struct SevenSeg sseg = {
         .x0 = 0,
         .y0 = 0,
         .charwidth = 17,
         .thick = 3,
-            //.charwidth = 16,
-            //.thick = 1,
+        //.charwidth = 16,
+        //.thick = 1,
         .spacing = 4,
     };
 
-    uint16_t i = 0;
-    uint16_t v;
-    uint16_t w;
-    int drawing = false;
+    init_isr();
+    sei();
+
+    // TODO show loading icon
+    sseg_number(&sseg, 0, 5, 0);
+
+    // request ADC meas
+    adc_async_start_measure_word(0);
+
+//    uint16_t cnt = 0;
+    uint16_t analog;
+    uint16_t count_boost_fail = 0;
     for (;;) {
-        sseg_number(&sseg, i, 5, 1);
+        if (adc_async_ready()) {
+            analog = adc_async_get_result_word();
+            adc_async_start_measure_word(0);
+
+            bool good_voltage = analog >= adc_target16;
+
+            if (g_pwm_on) {
+                if (good_voltage) {
+                    pwm_off();
+                    count_boost_fail = 0;
+                } else {
+                    count_boost_fail++;
+                }
+            }
+            else if (!good_voltage) {
+                pwm_on();
+            }
+
+            // If fail to reach target voltage in reasonable time,
+            // show weak battery icon and stop trying.
+            if (count_boost_fail > 50000 && analog < adc_target16_acceptable) {
+                // TODO weak battery icon
+                sseg_number(&sseg, 9999, 5, 0);
+                pwm_off();
+
+                for(;;) {}
+            }
+
+            // TODO synchronization?
+            if (tick_counter_changed) {
+                tick_counter_changed = false;
+                sseg_number(&sseg, tick_counter, 5, 0);
+            }
 
-        i++;
-        if (i == 9999) i = 0;
-        _delay_ms(100);
+//            if (++cnt > 10000) {
+//                sseg_number(&sseg, analog, 5, 0);
+//                cnt = 0;
+//            }
+        }
     }
 }