split to files

src/global_state.h

@@ -0,0 +1,15 @@
+/**
+ * Declarations of global variables
+ */
+
+#ifndef CPROJ_GLOBAL_VARIABLES_H
+#define CPROJ_GLOBAL_VARIABLES_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+extern volatile bool req_update_display;
+extern volatile bool is_weak_battery;
+extern volatile uint16_t timestamp_100ms;
+
+#endif //CPROJ_GLOBAL_VARIABLES_H

src/high_voltage.c

@@ -0,0 +1,140 @@
+/**
+ * High voltage source control logic
+ */
+
+#include "high_voltage.h"
+#include "iopins.h"
+#include "global_state.h"
+#include <stdbool.h>
+#include <avr/interrupt.h>
+#include <util/atomic.h>
+
+static volatile bool is_pwm_on = false;
+
+// tube starting voltage is 350V
+#define TURN_ON_VOLTAGE 355.0
+#define TURN_OFF_VOLTAGE 380.0
+#define MINIMAL_VOLTAGE 350.0
+
+// sensing via resistive divider
+#define VREF 1.1
+
+// in kiloohms
+#define R_UPPER 10000.0
+#define R_LOWER 27.0
+
+#define ADC_MAXVAL 1023
+
+#define RDIV_FACTOR   (R_LOWER / (R_UPPER + R_LOWER))
+
+/// ADC input voltage that's too low - PWM must start
+#define VSEN_TURN_ON  (TURN_ON_VOLTAGE  * RDIV_FACTOR)
+/// ADC input voltage that's too high - PWM must stop
+#define VSEN_TURN_OFF (TURN_OFF_VOLTAGE * RDIV_FACTOR)
+/// ADC input voltage that's lowest possible for the geiger tube to function
+#define VSEN_MINIMAL  (MINIMAL_VOLTAGE  * RDIV_FACTOR)
+
+// the above, but converted to ADC word
+#define ADCVAL_TURN_ON  ((uint16_t) (ADC_MAXVAL * (VSEN_TURN_ON  / VREF)))
+#define ADCVAL_TURN_OFF ((uint16_t) (ADC_MAXVAL * (VSEN_TURN_OFF / VREF)))
+#define ADCVAL_MINIMAL  ((uint16_t) (ADC_MAXVAL * (VSEN_MINIMAL  / VREF)))
+
+/// Channel used to measure VSEN
+#define VSEN_ADC_CHANNEL 0
+
+
+/// when capacitor was last fully charged
+static volatile uint16_t ts_cap_charged = 0;
+
+static void pwm_on()
+{
+    TCCR0A |= _BV(COM0B1);
+    is_pwm_on = true;
+}
+
+static void pwm_off()
+{
+    TCCR0A &= ~_BV(COM0B1);
+    is_pwm_on = false;
+}
+
+
+ISR(ADC_vect)
+{
+    // Service the boost converter
+    uint16_t analog = ADCW;
+
+    if (is_pwm_on) {
+        if (analog >= ADCVAL_TURN_OFF) {
+            pwm_off();
+            ts_cap_charged = timestamp_100ms;
+        } else {
+            // If fail to reach target voltage in reasonable time,
+            // show weak battery icon and stop trying.
+            if ((timestamp_100ms - ts_cap_charged) > 10 && analog < ADCVAL_MINIMAL) {
+                is_weak_battery = true;
+            }
+        }
+    } else if (analog < ADCVAL_TURN_ON) {
+        pwm_on();
+    }
+}
+
+
+static void init_pwm_out()
+{
+    // Output is OC0A
+    as_output(D5);
+
+    // initialize the timer
+    // Fast PWM mode, Output to OC0A
+
+    // 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 init_adc()
+{
+    ADCSRA =
+            // 128 prescaler -> 125 kHz
+            _BV(ADPS2) | _BV(ADPS1) | _BV(ADPS0)
+            // auto trigger
+            | _BV(ADATE)
+            // interrupt enable
+            | _BV(ADIE);
+
+    ADCSRB = 0; // free-running
+    DIDR0 = ADC0D; // disable the digital input buffer on the pin
+
+    ADMUX =
+            // internal ref 1.1V
+            _BV(REFS0) | _BV(REFS1)
+            // select channel
+            | VSEN_ADC_CHANNEL;
+
+    sbi(ADCSRA, ADEN);  // Enable ADC
+    sbi(ADCSRA, ADSC);  // Start
+}
+
+
+void init_high_voltage()
+{
+    init_pwm_out();
+    init_adc();
+}
+
+void hv_disable()
+{
+    ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+        // if ADC is disabled, the IRQ never fires and it won't be turned on
+        cbi(ADCSRA, ADEN);
+        // Turn it off
+        pwm_off();
+    }
+}

src/high_voltage.h

@@ -0,0 +1,14 @@
+/**
+ * High voltage
+ */
+
+#ifndef CPROJ_HIGH_VOLTAGE_H
+#define CPROJ_HIGH_VOLTAGE_H
+
+/// Init HV source. Requires interrupts enabled!
+void init_high_voltage();
+
+/// Disable the HV source
+void hv_disable();
+
+#endif //CPROJ_HIGH_VOLTAGE_H

src/main.c

@@ -1,229 +1,39 @@
-#include "twi.h"
-#include "ssd1306.h"
 #include "sevenseg.h"
-#include "adc.h"
-#include "iopins.h"
 #include <avr/interrupt.h>
 #include <util/atomic.h>
+#include <util/delay.h>
+#include <avr/sleep.h>
+#include "time_base.h"
+#include "high_voltage.h"
+#include "radiation.h"
+#include "user_interface.h"
 
-static void show_loading_icon();
-static void show_empty_battery_icon();
-static void shutdown_due_to_weak_battery();
-static void show_current_radiation();
-
-static void second_callback_irq();
-
-// tube starting voltage is 350V
-#define TURN_ON_VOLTAGE 355.0
-#define TURN_OFF_VOLTAGE 380.0
-#define MINIMAL_VOLTAGE 350.0
-
-// sensing via resistive divider
-#define VREF 1.1
-
-// in kiloohms
-#define R_UPPER 10000.0
-#define R_LOWER 27.0
-
-#define ADC_MAXVAL 1023
-
-#define RDIV_FACTOR   (R_LOWER / (R_UPPER + R_LOWER))
-
-/// ADC input voltage that's too low - PWM must start
-#define VSEN_TURN_ON  (TURN_ON_VOLTAGE  * RDIV_FACTOR)
-/// ADC input voltage that's too high - PWM must stop
-#define VSEN_TURN_OFF (TURN_OFF_VOLTAGE * RDIV_FACTOR)
-/// ADC input voltage that's lowest possible for the geiger tube to function
-#define VSEN_MINIMAL  (MINIMAL_VOLTAGE  * RDIV_FACTOR)
-
-// the above, but converted to ADC word
-#define ADCVAL_TURN_ON  ((uint16_t) (ADC_MAXVAL * (VSEN_TURN_ON  / VREF)))
-#define ADCVAL_TURN_OFF ((uint16_t) (ADC_MAXVAL * (VSEN_TURN_OFF / VREF)))
-#define ADCVAL_MINIMAL  ((uint16_t) (ADC_MAXVAL * (VSEN_MINIMAL  / VREF)))
-
-/// Channel used to measure VSEN
-#define VSEN_ADC_CHANNEL 0
-
-static struct SevenSeg sseg = {
-    .x0 = 0,
-    .y0 = 0,
-    .charwidth = 17,
-    .thick = 3,
-    //.charwidth = 16,
-    //.thick = 1,
-    .spacing = 4,
-};
-
-static volatile bool is_pwm_on = false;
-static volatile bool req_update_display = false;
-static volatile bool is_weak_battery = false;
-
-#define MEAS_BIN_COUNT 120
-typedef uint8_t meas_bin_t;
-#define MEAS_MAX_COUNT 255
-
-/// measurements in the last X seconds
-static volatile meas_bin_t measurements[MEAS_BIN_COUNT];
-/// Currently active measurement bin, increments once per second
-static volatile uint8_t meas_bin = 0;
-
-/// timestamp counted in units of 100ms
-static volatile uint16_t timestamp_100ms = 0;
-/// sub-second counter, counts 0-9 then overflows
-static volatile uint16_t subsec_counter = 0;
-
-// when capacitor was last fully charged
-static volatile uint16_t ts_cap_charged = 0;
-
-static inline void pwm_on() {
-    TCCR0A |= _BV(COM0B1);
-    is_pwm_on = true;
-}
-
-static void inline pwm_off() {
-    TCCR0A &= ~_BV(COM0B1);
-    is_pwm_on = false;
-}
-
-// geiger tube pin change interrupt
-ISR(INT0_vect)
-{
-    if (measurements[meas_bin] < MEAS_MAX_COUNT) {
-        measurements[meas_bin]++;
-    }
-    req_update_display = true;
-}
+/* globals */
+volatile bool req_update_display = false;
+volatile bool is_weak_battery = false;
 
-// 1 second counter
-ISR(TIMER1_COMPA_vect)
-{
-    timestamp_100ms++;
+static void shutdown_due_to_weak_battery();
 
-    subsec_counter++;
-    if (subsec_counter == 10) {
-        subsec_counter = 0;
-        second_callback_irq();
-    }
-}
 
-static void second_callback_irq()
+void __attribute__((noreturn)) main()
 {
-    meas_bin++;
-    if (meas_bin >= MEAS_BIN_COUNT) {
-        meas_bin = 0;
-    }
-    measurements[meas_bin] = 0;
-    req_update_display = true;
-}
-
-ISR(ADC_vect)
-{
-    // Service the boost converter
-    uint16_t analog = ADCW;
-
-    if (is_pwm_on) {
-        if (analog >= ADCVAL_TURN_OFF) {
-            pwm_off();
-            ts_cap_charged = timestamp_100ms;
-        } else {
-            // If fail to reach target voltage in reasonable time,
-            // show weak battery icon and stop trying.
-            if ((timestamp_100ms - ts_cap_charged) > 10 && analog < ADCVAL_MINIMAL) {
-                is_weak_battery = true;
-            }
-        }
-    }
-    else if (analog < ADCVAL_TURN_ON) {
-        pwm_on();
-    }
-}
+    init_user_interface();
 
-
-static void init_pcisr() {
-    as_input(D2);
-
-    // using INT0 - arduino pin D2
-    EICRA = _BV(ISC01) | _BV(ISC00); // rising edge
-    EIMSK = _BV(INT0);
-}
-
-static void init_pwm_out() {
-    // Output is OC0A
-    as_output(D5);
-
-    // initialize the timer
-    // Fast PWM mode, Output to OC0A
-
-    // 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 init_second_base() {
-    // CTC & presc=256
-   TCCR1B = (1 << WGM12) | (1 << CS12);
-   TIMSK1 = (1 << OCIE1A); // Enable CTC interrupt
-   OCR1A   = 6250; // 100ms
-}
-
-static void vsen_adc_init() {
-    ADCSRA =
-            // 128 prescaler -> 125 kHz
-            _BV(ADPS2) | _BV(ADPS1) | _BV(ADPS0)
-            // auto trigger
-            | _BV(ADATE)
-            // interrupt enable
-            | _BV(ADIE);
-
-    ADCSRB = 0; // free-running
-    DIDR0 = ADC0D; // disable the digital input buffer on the pin
-
-    ADMUX  =
-            // internal ref 1.1V
-            _BV(REFS0) | _BV(REFS1)
-            // select channel
-            | VSEN_ADC_CHANNEL;
-
-    sbi(ADCSRA, ADEN);  // Enable ADC
-    sbi(ADCSRA, ADSC);  // Start
-}
-
-void __attribute__((noreturn)) main() {
-    // clear the measurement buffer
-    memset((void*) measurements, 0, sizeof(measurements));
-
-    TWI_Init();
-
-
-    init_second_base();
-
-    init_pwm_out();
-
-    ssd1306_128x32_i2c_init();
-    ssd1306_clearScreen();
-
-    // TODO use ADC interrupt
-
-    init_pcisr();
-
-    // TODO show loading icon (can't show anything useful at least until the first tick arrives)
-    show_loading_icon();
+    init_timebase();
+    init_radiation();
 
     // --- let's go ---
     sei();
 
-    vsen_adc_init();
+    // this needs interrupts enabled
+    init_high_voltage();
 
     for (;;) {
         _delay_ms(100);
 
         // check if redraw is needed
         bool update_display = false;
-        ATOMIC_BLOCK(ATOMIC_FORCEON) {
+        ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
             update_display = req_update_display;
             req_update_display = false;
         }
@@ -238,37 +48,18 @@ void __attribute__((noreturn)) main() {
     }
 }
 
-void show_current_radiation()
-{
-    // TODO
-    sseg_number(&sseg, timestamp_100ms, 5, 0);
-}
 
 void __attribute__((noreturn)) shutdown_due_to_weak_battery()
 {
-    pwm_off();
-
-    show_empty_battery_icon();
-
     cli();
+    hv_disable();
 
+    show_empty_battery_icon();
     // try to preserve power; but the display will still drain the battery.
     // we should probably shut it off too.
 
-    for(;;) {
+    for (;;) {
         sleep_enable();
         sleep_cpu();
     }
 }
-
-void show_empty_battery_icon()
-{
-    // TODO
-    sseg_number(&sseg, 9999, 5, 0);
-}
-
-void show_loading_icon()
-{
-    // TODO
-    sseg_number(&sseg, 0, 5, 0);
-}

src/radiation.c

@@ -0,0 +1,52 @@
+/**
+ * Radiation counting
+ */
+
+#include "radiation.h"
+#include "time_base.h"
+#include "global_state.h"
+#include "iopins.h"
+
+#include <avr/interrupt.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+
+#define MEAS_BIN_COUNT 120
+typedef uint8_t meas_bin_t;
+#define MEAS_MAX_COUNT 255
+
+/// measurements in the last X seconds
+static volatile meas_bin_t measurements[MEAS_BIN_COUNT];
+/// Currently active measurement bin, increments once per second
+static volatile uint8_t meas_bin = 0;
+
+// geiger tube pin change interrupt
+ISR(INT0_vect)
+{
+    if (measurements[meas_bin] < MEAS_MAX_COUNT) {
+        measurements[meas_bin]++;
+    }
+    req_update_display = true;
+}
+
+void second_callback_irq()
+{
+    meas_bin++;
+    if (meas_bin >= MEAS_BIN_COUNT) {
+        meas_bin = 0;
+    }
+    measurements[meas_bin] = 0;
+    req_update_display = true;
+}
+
+void init_radiation() {
+    // clear the measurement buffer
+    memset((void*) measurements, 0, sizeof(measurements));
+
+    as_input(D2);
+
+    // using INT0 - arduino pin D2
+    EICRA = _BV(ISC01) | _BV(ISC00); // rising edge
+    EIMSK = _BV(INT0);
+}

src/radiation.h

@@ -0,0 +1,10 @@
+/**
+ * Radiation counting
+ */
+
+#ifndef CPROJ_RADIATION_H
+#define CPROJ_RADIATION_H
+
+void init_radiation();
+
+#endif //CPROJ_RADIATION_H

src/sevenseg.h

@@ -6,6 +6,7 @@
 #define CPROJ_SEVENSEG_H
 
 #include <stdbool.h>
+#include <stdint.h>
 
 struct SevenSeg {
   uint8_t x0;

src/time_base.c

@@ -0,0 +1,33 @@
+/**
+ * Time base
+ */
+
+#include "time_base.h"
+
+#include <stdint.h>
+#include <avr/interrupt.h>
+
+/// timestamp counted in units of 100ms
+volatile uint16_t timestamp_100ms = 0;
+/// sub-second counter, counts 0-9 then overflows
+static volatile uint16_t subsec_counter = 0;
+
+// 100ms counter
+ISR(TIMER1_COMPA_vect)
+{
+    timestamp_100ms++;
+
+    subsec_counter++;
+    if (subsec_counter == 10) {
+        subsec_counter = 0;
+        second_callback_irq();
+    }
+}
+
+void init_timebase()
+{
+    // CTC & presc=256
+    TCCR1B = (1 << WGM12) | (1 << CS12);
+    TIMSK1 = (1 << OCIE1A); // Enable CTC interrupt
+    OCR1A = 6250; // 100ms
+}

src/time_base.h

@@ -0,0 +1,12 @@
+/**
+ * TODO file description
+ */
+
+#ifndef CPROJ_TIME_BASE_H
+#define CPROJ_TIME_BASE_H
+
+
+void second_callback_irq();
+void init_timebase();
+
+#endif //CPROJ_TIME_BASE_H

src/user_interface.c

@@ -0,0 +1,48 @@
+/**
+ * Dispay
+ */
+
+#include "user_interface.h"
+#include "twi.h"
+#include "ssd1306.h"
+#include "sevenseg.h"
+#include "global_state.h"
+
+static struct SevenSeg sseg = {
+        .x0 = 0,
+        .y0 = 0,
+        .charwidth = 17,
+        .thick = 3,
+        //.charwidth = 16,
+        //.thick = 1,
+        .spacing = 4,
+};
+
+void init_user_interface()
+{
+    TWI_Init();
+    ssd1306_128x32_i2c_init();
+    ssd1306_clearScreen();
+
+    // can't show anything useful at least until the first tick arrives, but more than 1 tick is needed
+    show_loading_icon();
+}
+
+
+void show_current_radiation()
+{
+    // TODO
+    sseg_number(&sseg, timestamp_100ms, 5, 0);
+}
+
+void show_empty_battery_icon()
+{
+    // TODO
+    sseg_number(&sseg, 9999, 5, 0);
+}
+
+void show_loading_icon()
+{
+    // TODO
+    sseg_number(&sseg, 0, 5, 0);
+}

src/user_interface.h

@@ -0,0 +1,16 @@
+/**
+ * UI
+ */
+
+#ifndef CPROJ_USER_INTERFACE_H
+#define CPROJ_USER_INTERFACE_H
+
+void init_user_interface();
+
+void show_current_radiation();
+
+void show_empty_battery_icon();
+
+void show_loading_icon();
+
+#endif //CPROJ_USER_INTERFACE_H