merged fsm branch, finally

1 files changed, 117 insertions, 0 deletions

diff --git a/spaghetti-monster/fsm-wdt.c b/spaghetti-monster/fsm-wdt.c
new file mode 100644
index 0000000..ff96ffb
--- /dev/null
+++ b/spaghetti-monster/fsm-wdt.c
@@ -0,0 +1,117 @@
+/*
+ * fsm-wdt.c: WDT (Watch Dog Timer) functions for SpaghettiMonster.
+ *
+ * Copyright (C) 2017 Selene ToyKeeper
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef FSM_WDT_C
+#define FSM_WDT_C
+
+#include <avr/interrupt.h>
+#include <avr/wdt.h>
+
+void WDT_on()
+{
+    // interrupt every 16ms
+    //cli();                          // Disable interrupts
+    wdt_reset();                    // Reset the WDT
+    WDTCR |= (1<<WDCE) | (1<<WDE);  // Start timed sequence
+    WDTCR = (1<<WDIE);              // Enable interrupt every 16ms
+    //sei();                          // Enable interrupts
+}
+
+inline void WDT_off()
+{
+    //cli();                          // Disable interrupts
+    wdt_reset();                    // Reset the WDT
+    MCUSR &= ~(1<<WDRF);            // Clear Watchdog reset flag
+    WDTCR |= (1<<WDCE) | (1<<WDE);  // Start timed sequence
+    WDTCR = 0x00;                   // Disable WDT
+    //sei();                          // Enable interrupts
+}
+
+// clock tick -- this runs every 16ms (62.5 fps)
+ISR(WDT_vect) {
+    // detect and emit button change events
+    uint8_t was_pressed = button_last_state;
+    uint8_t pressed = button_is_pressed();
+    if (was_pressed != pressed) PCINT_inner(pressed);
+
+    //if (ticks_since_last_event < 0xff) ticks_since_last_event ++;
+    // increment, but loop from max back to half
+    ticks_since_last_event = (ticks_since_last_event + 1) \
+                             | (ticks_since_last_event & 0x8000);
+
+    // if time since last event exceeds timeout,
+    // append timeout to current event sequence, then
+    // send event to current state callback
+
+    // preload recent events
+    uint8_t le_num = last_event_num();
+    uint8_t last_event = 0;
+    uint8_t prev_event = 0;
+    if (le_num >= 1) last_event = current_event[le_num-1];
+    if (le_num >= 2) prev_event = current_event[le_num-2];
+
+    // callback on each timer tick
+    if (last_event == A_HOLD) {
+        emit(EV_tick, 0);  // override tick counter while holding button
+    }
+    else {
+        emit(EV_tick, ticks_since_last_event);
+    }
+
+    // user held button long enough to count as a long click?
+    if (last_event == A_PRESS) {
+        if (ticks_since_last_event >= HOLD_TIMEOUT) {
+            push_event(A_HOLD);
+            emit_current_event(0);
+        }
+    }
+
+    // user is still holding button, so tick
+    else if (last_event == A_HOLD) {
+        emit_current_event(ticks_since_last_event);
+    }
+
+    // detect completed button presses with expired timeout
+    else if (last_event == A_RELEASE) {
+        // no timeout required when releasing a long-press
+        // TODO? move this logic to PCINT() and simplify things here?
+        if (prev_event == A_HOLD) {
+            //emit_current_event(0);  // should have been emitted by PCINT
+            empty_event_sequence();
+        }
+        // end and clear event after release timeout
+        else if (ticks_since_last_event >= RELEASE_TIMEOUT) {
+            push_event(A_RELEASE_TIMEOUT);
+            emit_current_event(0);
+            empty_event_sequence();
+        }
+    }
+
+    #if defined(USE_LVP) || defined(USE_THERMAL_REGULATION)
+    // start a new ADC measurement every 4 ticks
+    static uint8_t adc_trigger = 0;
+    adc_trigger ++;
+    if (0 == (adc_trigger & 3)) {
+        ADCSRA |= (1 << ADSC) | (1 << ADIE);
+        adcint_enable = 1;
+    }
+    #endif
+}
+
+#endif