added some examples, shortened some lcd functions

examples/Makefile

@@ -11,14 +11,14 @@ EFUSE = 0x05
 
 ## === Source files ===
 # Main C file
-MAIN = uart_isr.c
+MAIN = lcd_test.c
 # Extra C files in this folder
 LOCAL_SOURCE =
 
 # Library directory (with C files)
 EXTRA_SOURCE_DIR = lib/
 # C files in the library directory
-EXTRA_SOURCE_FILES = uart.c
+EXTRA_SOURCE_FILES = uart.c lcd.c
 
 
 ## === Programmer ===

examples/lcd_config.h

@@ -0,0 +1,13 @@
+#pragma once
+
+// Pin config file for LCD.
+
+#include "lib/arduino_pins.h"
+
+#define LCD_RS D2
+#define LCD_RW D3
+#define LCD_E  D4
+#define LCD_D4 D5
+#define LCD_D5 D6
+#define LCD_D6 D7
+#define LCD_D7 D8

examples/lcd_test.c

@@ -0,0 +1,58 @@
+//
+// Example of basic LCD usage
+//
+
+#include <avr/io.h>
+#include <avr/pgmspace.h>
+#include <util/delay.h>
+
+#include "lib/calc.h"
+#include "lib/lcd.h"
+
+// Bytes for custom glyph
+
+// Here's a good glyph generator you can use:
+//     http://omerk.github.io/lcdchargen/
+
+const uint8_t glyph[] PROGMEM = {
+	0b00000,
+	0b00111,
+	0b01101,
+	0b11101,
+	0b10001,
+	0b10001,
+	0b10001,
+	0b11111
+};
+
+
+void main()
+{
+	lcd_init();
+
+	// Define custom glyph at character 0
+	lcd_glyph_pgm(0, glyph);
+
+	// After writing a glyph, the address is changed
+	// So we need to fix that:
+	lcd_xy(0, 0);
+
+	// Print a string
+	lcd_puts("Hello");
+
+	// Use _pgm for strings in program memory
+	// Here we print string at position xy
+	lcd_puts_xy_pgm(0, 1, PSTR("String from PGM "));
+
+	// print the custom glyph
+	lcd_putc(0);
+
+	// enable blink/bar cursor type
+	lcd_cursor(CURSOR_BOTH);
+
+	lcd_puts_xy(5, 2, "Third line?");
+	lcd_puts_xy(3, 3, "Fourth line!");
+
+	// end
+	while(1);
+}

examples/uart_isr.c

@@ -1,8 +1,11 @@
+//
+// Example of UART with interrupts
+//
+
 #include <avr/io.h>
 #include <util/delay.h>
 #include <avr/pgmspace.h>
 #include <avr/interrupt.h>
-#include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
 

examples/uart_simple.c

@@ -1,8 +1,11 @@
+//
+// Example of basic UART usage
+//
+
 #include <avr/io.h>
 #include <util/delay.h>
 #include <avr/pgmspace.h>
 #include <avr/interrupt.h>
-#include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
 
@@ -21,8 +24,8 @@ void main()
 	// Printing a string
 	uart_puts("Simple UART example!\r\n");
 
-	// You can put your string literals in the program memory
-	// and use the _pgm variant:
+	// Use _pgm for strings in program memory
+	// (PSTR macro is defined in avr/pgmspace.h)
 	uart_puts_pgm(PSTR("Program memory string example\r\n"));
 
 	// print a char. This is an alias for uart_tx
@@ -32,24 +35,26 @@ void main()
 	uart_nl();
 
 	// Printing numbers is also easy
-	// Look in the library file for more info
+	// Look in `uart.h` for more info
 	uart_putn(123);
 	uart_nl();
 
-	// Print int as float (adds decimal point)
+	// Print int as float (adds decimal point at 4th place from the end)
 	uart_puti(31415, 4);
 	uart_nl();
 
 
-
 	// --- receive example ---
 
 	// Example of listening for input
 	while(1) {
+
 		// If something is received
 		if (uart_rx_ready()) {
+
 			// Get the received byte
 			char c = uart_rx();
+
 			// Send it back, twice
 			uart_tx(c);
 			uart_tx(c);

lib/lcd.c

@@ -61,10 +61,10 @@ void lcd_init()
 	_delay_us(100);
 
 	// Configure the display
-	lcd_write_command(LCD_IFACE_4BIT_2LINE);
-	lcd_write_command(LCD_DISABLE);
-	lcd_write_command(LCD_CLEAR);
-	lcd_write_command(LCD_MODE_INC);
+	lcd_command(LCD_IFACE_4BIT_2LINE);
+	lcd_command(LCD_DISABLE);
+	lcd_command(LCD_CLEAR);
+	lcd_command(LCD_MODE_INC);
 
 	// mark as enabled
 	lcd_enable();
@@ -130,7 +130,7 @@ uint8_t _lcd_read_byte()
 
 
 /** Write an instruction byte */
-void lcd_write_command(uint8_t bb)
+void lcd_command(uint8_t bb)
 {
 	_lcd_wait_bf();
 	pin_down(LCD_RS);  // select instruction register
@@ -139,7 +139,7 @@ void lcd_write_command(uint8_t bb)
 
 
 /** Write a data byte */
-void lcd_write_data(uint8_t bb)
+void lcd_write(uint8_t bb)
 {
 	_lcd_wait_bf();
 	pin_up(LCD_RS);  // select data register
@@ -156,7 +156,7 @@ uint8_t lcd_read_bf_addr()
 
 
 /** Read CGRAM or DDRAM */
-uint8_t lcd_read_ram()
+uint8_t lcd_read()
 {
 	pin_up(LCD_RS);
 	return _lcd_read_byte();
@@ -194,17 +194,26 @@ void lcd_puts(char* str_p)
 }
 
 
+/** Print from progmem */
+void lcd_puts_pgm(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_data(c);
+	lcd_write(c);
 }
 
 
 /** Set cursor position */
 void lcd_xy(const uint8_t x, const uint8_t y)
 {
-	lcd_set_addr(LCD_ROW_ADDR[y] + (x));
+	lcd_addr(LCD_ROW_ADDR[y] + (x));
 }
 
 
@@ -216,14 +225,14 @@ void lcd_cursor(uint8_t type)
 {
 	_lcd_old_cursor = (type & CURSOR_BOTH);
 
-	if (_lcd_enabled) lcd_write_command(LCD_CURSOR_NONE | _lcd_old_cursor);
+	if (_lcd_enabled) lcd_command(LCD_CURSOR_NONE | _lcd_old_cursor);
 }
 
 
 /** Display display (preserving cursor) */
 void lcd_disable()
 {
-	lcd_write_command(LCD_DISABLE);
+	lcd_command(LCD_DISABLE);
 	_lcd_enabled = false;
 }
 
@@ -239,46 +248,46 @@ void lcd_enable()
 /** Go home */
 void lcd_home()
 {
-	lcd_write_command(LCD_HOME);
+	lcd_command(LCD_HOME);
 }
 
 
 /** Clear the screen */
 void lcd_clear()
 {
-	lcd_write_command(LCD_CLEAR);
+	lcd_command(LCD_CLEAR);
 }
 
 
 /** Define a glyph */
-void lcd_define_glyph(const uint8_t index, const uint8_t* array)
+void lcd_glyph(const uint8_t index, const uint8_t* array)
 {
-	lcd_set_addr_cgram(index * 8);
+	lcd_addr_cg(index * 8);
 	for (uint8_t i = 0; i < 8; ++i)	{
-		lcd_write_data(array[i]);
+		lcd_write(array[i]);
 	}
 }
 
 
 /** Define a glyph */
-void lcd_define_glyph_pgm(const uint8_t index, const uint8_t* array)
+void lcd_glyph_pgm(const uint8_t index, const uint8_t* array)
 {
-	lcd_set_addr_cgram(index * 8);
+	lcd_addr_cg(index * 8);
 	for (uint8_t i = 0; i < 8; ++i)	{
-		lcd_write_data(pgm_read_byte(&array[i]));
+		lcd_write(pgm_read_byte(&array[i]));
 	}
 }
 
 
 /** Set address in CGRAM */
-void lcd_set_addr_cgram(const uint8_t acg)
+void lcd_addr_cg(const uint8_t acg)
 {
-	lcd_write_command(0b01000000 | ((acg) & 0b00111111));
+	lcd_command(0b01000000 | ((acg) & 0b00111111));
 }
 
 
 /** Set address in DDRAM */
-void lcd_set_addr(const uint8_t add)
+void lcd_addr(const uint8_t add)
 {
-	lcd_write_command(0b10000000 | ((add) & 0b01111111));
+	lcd_command(0b10000000 | ((add) & 0b01111111));
 }

lib/lcd.h

@@ -19,9 +19,12 @@
 //
 
 #include <stdint.h>
+#include <stdbool.h>
+
+// File with configs
 #include "lcd_config.h"
 
-// Commands
+// --- Commands ---
 
 // Clear screen (reset)
 #define LCD_CLEAR 0b00000001
@@ -70,28 +73,34 @@
 void lcd_init();
 
 /** Write an instruction byte */
-void lcd_write_command(uint8_t bb);
+void lcd_command(uint8_t bb);
 
 /** Write a data byte */
-void lcd_write_data(uint8_t bb);
+void lcd_write(uint8_t bb);
 
 /** Read BF & Address */
 uint8_t lcd_read_bf_addr();
 
 /** Read CGRAM or DDRAM */
-uint8_t lcd_read_ram();
+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_pgm(const char* str_p);
+
 /** Sedn a char to LCD */
 void lcd_putc(const char c);
 
 /** Show string at X, Y */
-#define lcd_str_xy(x, y, str_p) do { lcd_xy((x), (y)); lcd_puts((str_p)); } while(0)
+#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_pgm(x, y, str_p) do { lcd_xy((x), (y)); lcd_puts_pgm((str_p)); } while(0)
 
 /** Show char at X, Y */
-#define lcd_char_xy(x, y, c) do { lcd_xy((x), (y)); lcd_putc((c)); } while(0)
+#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);
@@ -115,14 +124,14 @@ void lcd_home();
 /** Clear the screen */
 void lcd_clear();
 
-/** Define a glyph */
-void lcd_define_glyph(const uint8_t index, const uint8_t* array);
+/** 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_define_glyph_pgm(const uint8_t index, const uint8_t* array);
+void lcd_glyph_pgm(const uint8_t index, const uint8_t* array);
 
 /** Set address in CGRAM */
-void lcd_set_addr_cgram(const uint8_t acg);
+void lcd_addr_cg(const uint8_t acg);
 
 /** Set address in DDRAM */
-void lcd_set_addr(const uint8_t add);
+void lcd_addr(const uint8_t add);