merged irq-refactor branch, which fixes some small but long-standing issues:

- fixed occasional short/aborted frames in aux LED sleep animation
- fixed rare case of bogus voltage and/or temperature values
- fixed issue where nice_delay_ms() didn't work in setup()
- fixed theoretical possibility of extra-noisy buttons causing a hang
- fixed reboot loop which happened after any crashes
- fixed issue where button press in sleep mode could occasionally crash
  (but the issue may have been created by this branch before being fixed by it)
- reduced occasional missed button events while asleep
  (still seems to happen but not nearly as much)

Also does some other things:
- cleans up the ADC code significantly
- cleans up the WDT code
- adds a voltage stabilizer/lowpass option (enabled on t1634 builds)
- greatly reduces time spent per interrupt,
  which might make a future PWM-DSM technique possible
- moves most interrupt-handling logic to a non-critical code path,
  deferring that code until timing doesn't matter as much
- sped up button state measurements
- very slightly reduces power used in sleep mode

1 files changed, 22 insertions, 7 deletions

diff --git a/spaghetti-monster/fsm-standby.c b/spaghetti-monster/fsm-standby.c
index 44b047a..e4ef92c 100644
--- a/spaghetti-monster/fsm-standby.c
+++ b/spaghetti-monster/fsm-standby.c
@@ -42,16 +42,19 @@ void sleep_until_eswitch_pressed()
     // make sure switch isn't currently pressed
     while (button_is_pressed()) {}
     empty_event_sequence();  // cancel pending input on suspend
-    //PCINT_since_WDT = 0;  // ensure PCINT won't ignore itself
-
-    PCINT_on();  // wake on e-switch event
 
     #ifdef TICK_DURING_STANDBY
+    // detect which type of event caused a wake-up
+    irq_adc = 0;
+    irq_wdt = 0;
+    irq_pcint = 0;
     while (go_to_standby) {
-        f_wdt = 0;  // detect if WDT was what caused a wake-up
     #else
         go_to_standby = 0;
     #endif
+
+        PCINT_on();  // wake on e-switch event
+
         // configure sleep mode
         set_sleep_mode(SLEEP_MODE_PWR_DOWN);
 
@@ -65,10 +68,19 @@ void sleep_until_eswitch_pressed()
         sleep_disable();
 
     #ifdef TICK_DURING_STANDBY
-        // determine what woke us up... WDT or PCINT
-        if (! f_wdt) {  // PCINT went off; wake up
+        // determine what woke us up...
+        if (irq_pcint) {  // button pressed; wake up
             go_to_standby = 0;
         }
+        if (irq_adc) {  // ADC done measuring
+            adcint_enable = 1;
+            ADC_inner();
+            //ADC_off();  // takes care of itself
+            //irq_adc = 0;  // takes care of itself
+        }
+        if (irq_wdt) {  // generate a sleep tick
+            WDT_inner();
+        }
     }
     #endif
 
@@ -78,7 +90,10 @@ void sleep_until_eswitch_pressed()
     #endif
 
     // go back to normal running mode
-    //PCINT_on();  // should be on already
+    // PCINT not needed any more, and can cause problems if on
+    // (occasional reboots on wakeup-by-button-press)
+    PCINT_off();
+    // restore normal awake-mode interrupts
     ADC_on();
     WDT_on();
 }