Low battery bugfix:

[heater.git] / firmware / main.c

diff --git a/firmware/main.c b/firmware/main.c
index 0aa1c4abdfb3be3c77dece344f54abc84d24083b..65801e81b05fd74192238c0d9892c2d87c9c0b24 100644 (file)
--- a/firmware/main.c
+++ b/firmware/main.c
@@ -21,21 +21,15 @@
  * Buttons:
  * There are two buttons (+ and -). Any button can wake the system up from
  * the power-down state.
- * TODO: When the system is woken up by the "-" button,
- * it starts with the minimum output power, when it is woken up by the "+"
- * button, it start with the maximum output power.
  * When running, the "-" button is used for decreasing the output power,
  * the "+" button is for increasing it.
- * When on the lowest power state, the "-" button switches the system off.
- * Long "-" button press switches the system off, long "+" button
- * press sets the output power to maximum.
+ * Any long button press switches the system off.
  *
  * Status LED:
  * When powering up by a button press, the LED goes on to provide a visual
  * feedback, and is switched off after the button is released.
- * After a button press, the # of blinks of the LED reflects the
- * chosen output power level for some time. Afterwards, it displays
- * the battery level.
+ * It displays the current power level and current battery voltage
+ * using # of blinks with different blinking lengths.
  * When the battery is completely exhausted, the output power is switched
  * off, the LED keeps blinking for some time, and then the whole system is
  * switched off to avoid deep discharge of the battery.
@@ -59,6 +53,16 @@
 #define WAKEUP_POLL 50 // msec
 #define WAKEUP_LIMIT 5 // times WAKEUP_POLL
 
+// #define BUTTONS_REVERSE
+
+#ifdef BUTTONS_REVERSE
+#      define BUTTON1  PB0
+#      define BUTTON2  PB1
+#else
+#      define BUTTON1  PB1
+#      define BUTTON2  PB0
+#endif /* !BUTTONS_REVERSE */
+
 /* which state (output on or output off) are we measuring now */
 static volatile unsigned char adc_type, adc_drop;
 #define ADC_RUNAVG_SHIFT 5     // running average shift on batt_on, batt_off
@@ -75,9 +79,10 @@ static volatile uint16_t batt_on, batt_off; // measured voltage
                                * (1024UL * (mV)) \
                                / (6UL * ADC_1100MV_VALUE)) >> 8))
 static unsigned char batt_levels[] = {
-       MV_TO_ADC8(3350),
-       MV_TO_ADC8(3700),
-       MV_TO_ADC8(3900),
+       MV_TO_ADC8(3000), // below this, do not enable load, and switch off
+       MV_TO_ADC8(3150), // below this, switch off after some time
+       MV_TO_ADC8(3450), // battery low
+       MV_TO_ADC8(3800), // battery ok, above that almost full
 };
 #define BATT_N_LEVELS  (sizeof(batt_levels) / sizeof(batt_levels[0]))
 
@@ -107,9 +112,7 @@ static unsigned char power_levels[] = {
 #define N_POWER_LEVELS (sizeof(power_levels) / sizeof(power_levels[0]))
 
 static unsigned char power_level = 0; // selected power level
-static unsigned char power_level_changed; // for visual feedback
 
-#define LED_PWRCHANGE_COUNT    5
 #define LED_BATTEMPTY_COUNT    60
 
 /* timing by WDT */
@@ -267,9 +270,9 @@ static void buttons_susp()
 static unsigned char buttons_pressed()
 {
        return (
-               (PINB & _BV(PB0) ? 0 : 1)
+               (PINB & _BV(BUTTON1) ? 0 : 1)
                |
-               (PINB & _BV(PB1) ? 0 : 2)
+               (PINB & _BV(BUTTON2) ? 0 : 2)
        );
 }
 
@@ -379,13 +382,21 @@ static unsigned char battery_level()
 static void status_led_next_pattern()
 {
        static unsigned char battery_exhausted;
+       static unsigned char display_power_level;
 
-       if (power_level_changed) {
-               power_level_changed--;
+       if (display_power_level) {
                n_blinks = power_level + 1;
+               if (batt_on >> 8 == batt_off >> 8) { // load unplugged
+                       n_blinks = 2 * n_blinks;
+                       blink_on_time = 0;
+                       blink_off_time = 0;
+               } else {
+                       blink_on_time = 2;
+                       blink_off_time = 2;
+               }
        } else {
                unsigned char b_level = battery_level();
-               if (b_level) {
+               if (b_level > 1) {
                        battery_exhausted = 0;
                } else if (battery_exhausted) {
                        if (!--battery_exhausted)
@@ -394,12 +405,13 @@ static void status_led_next_pattern()
                        battery_exhausted = LED_BATTEMPTY_COUNT;
                }
 
-               n_blinks = b_level + 1;
+               n_blinks = b_level ? b_level : 1;
+               blink_on_time = b_level ? 4 : 2;
+               blink_off_time = 0;
        }
 
-       blink_on_time = 2;
-       blink_off_time = 1;
-       blink_counter = 10;
+       blink_counter = 12;
+       display_power_level = !display_power_level;
 }
 
 static void timer_blink()
@@ -422,23 +434,13 @@ static void timer_blink()
 static void button_pressed(unsigned char button, unsigned char long_press)
 {
        // ignore simlultaneous button 1 and 2 press
-       // Note: we set power_level_changed after each button press,
-       // even when the power is at maximum, to provide visual feedback
-       // with status LED.
        if (long_press) {
-               if (button == 1) {
-                       power_down();
-                       return;
-               } else if (button == 2) {
-                       power_level = N_POWER_LEVELS-1;
-               }
+               power_down();
+               return;
        } else { // short press
                if (button == 1) {
                        if (power_level > 0) {
                                --power_level;
-                       } else {
-                               power_down();
-                               return;
                        }
                } else if (button == 2) {
                        if (power_level < N_POWER_LEVELS-1) {
@@ -446,7 +448,6 @@ static void button_pressed(unsigned char button, unsigned char long_press)
                        }
                }
        }
-       power_level_changed = LED_PWRCHANGE_COUNT;
        status_led_next_pattern();
 }
 
@@ -563,6 +564,10 @@ int main()
                                log_byte(batt_on >> 8);
 #endif
                        }
+                       if (jiffies == 0) {
+                               log_byte(batt_on >> 8);
+                               log_byte(batt_off >> 8);
+                       }
                        log_flush();
                }
        }