1 files changed, 105 insertions, 0 deletions
diff --git a/fsm/standby.c b/fsm/standby.c
new file mode 100644
index 0000000..5def07c
--- /dev/null
+++ b/fsm/standby.c
@@ -0,0 +1,105 @@
+// fsm-standby.c: standby mode functions for SpaghettiMonster.
+// Copyright (C) 2017-2023 Selene ToyKeeper
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include <avr/interrupt.h>
+#include <avr/sleep.h>
+
+#include "fsm-adc.h"
+#include "fsm-wdt.h"
+#include "fsm-pcint.h"
+
+// low-power standby mode used while off but power still connected
+#define standby_mode sleep_until_eswitch_pressed
+void sleep_until_eswitch_pressed()
+{
+    #ifdef TICK_DURING_STANDBY
+    WDT_slow();
+    #else
+    WDT_off();
+    #endif
+
+    ADC_off();
+
+    // make sure switch isn't currently pressed
+    while (button_is_pressed()) {}
+    empty_event_sequence();  // cancel pending input on suspend
+
+    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) {
+    #else
+        go_to_standby = 0;
+    #endif
+
+        // configure sleep mode
+        #ifdef TICK_DURING_STANDBY
+            // needs a special sleep mode during measurements
+            if (adc_active_now) adc_sleep_mode();
+            else
+        #endif
+        set_sleep_mode(SLEEP_MODE_PWR_DOWN);
+
+        sleep_enable();
+        #ifdef BODCR  // only do this on MCUs which support it
+        sleep_bod_disable();
+        #endif
+        sleep_cpu();  // wait here
+
+        // something happened; wake up
+        sleep_disable();
+
+    #ifdef TICK_DURING_STANDBY
+        // determine what woke us up...
+        if (irq_pcint) {  // button pressed; wake up
+            go_to_standby = 0;
+        }
+        if (irq_adc) {  // ADC done measuring
+            #ifndef USE_LOWPASS_WHILE_ASLEEP
+            adc_reset = 1;  // don't lowpass while asleep
+            #endif
+            adc_deferred_enable = 1;
+            adc_deferred();
+            //ADC_off();  // takes care of itself
+            //irq_adc = 0;  // takes care of itself
+        }
+        if (irq_wdt) {  // generate a sleep tick
+            WDT_inner();
+        }
+    }
+    #endif
+
+    // don't lowpass immediately after waking
+    // also, reset thermal history
+    adc_reset = 2;
+
+    // go back to normal running mode
+    // 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();
+}
+
+#ifdef USE_IDLE_MODE
+void idle_mode()
+{
+    // configure sleep mode
+    set_sleep_mode(SLEEP_MODE_IDLE);
+
+    sleep_enable();
+    sleep_cpu();  // wait here
+
+    // something happened; wake up
+    sleep_disable();
+}
+#endif
+