From 90ffd122f4387d18e8d7cf7d2a507c719409d4e5 Mon Sep 17 00:00:00 2001
From: "Jan \"Yenya\" Kasprzak" <kas@fi.muni.cz>
Date: Tue, 21 May 2013 00:34:06 +0200
Subject: [PATCH] Watchdog-based timing

TODO: remove the sub-LSB PWM scaling, add deeper sleep states.
---
 firmware/buttons.c | 10 +++++++---
 firmware/main.c    |  6 ------
 firmware/tmr.c     | 31 ++++++++-----------------------
 3 files changed, 15 insertions(+), 32 deletions(-)

diff --git a/firmware/buttons.c b/firmware/buttons.c
index 017a56c..80ecce6 100644
--- a/firmware/buttons.c
+++ b/firmware/buttons.c
@@ -7,6 +7,10 @@
 #include "lights.h"
 
 #define WAKEUP_LIMIT	5	// times 100 ms
+#define SHORT_PRESS_MIN 2       // in jiffies (16 Hz ticks)
+#define SHORT_PRESS_MAX 5
+#define LONG_PRESS_MIN  10
+
 static uint16_t button_start[3];
 union {
 	unsigned char all;
@@ -166,16 +170,16 @@ static void handle_button(unsigned char button, unsigned char cur,
 	} else if (cur && prev) {           // --- is still pressed ---
 		uint16_t duration = jiffies - button_start[button];
 
-		if (duration > 160) {
+		if (duration >= LONG_PRESS_MIN) {
 			set_status_led(button, on1_pattern);
 				// acknowledge long press
 		}
 	} else if (!cur && prev) {            // --- just released ---
 		uint16_t duration = jiffies - button_start[button];
 
-		if (duration > 6 && duration < 60) {
+		if (duration >= SHORT_PRESS_MIN && duration < SHORT_PRESS_MAX) {
 			short_press(button);
-		} else if (duration > 160) {
+		} else if (duration > LONG_PRESS_MIN) {
 			set_status_led(button, NULL);
 			long_press(button);
 		}
diff --git a/firmware/main.c b/firmware/main.c
index 393f47d..0e33957 100644
--- a/firmware/main.c
+++ b/firmware/main.c
@@ -3,14 +3,11 @@
 #include <avr/sleep.h>
 #include <avr/interrupt.h>
 #include <avr/power.h>
-#include <avr/wdt.h>
 
 #include "lights.h"
 
 static void hw_setup()
 {
-	wdt_enable(WDTO_1S);
-
 	init_battery();
 	init_pwm();
 	init_adc();
@@ -34,8 +31,6 @@ static void hw_suspend()
 	susp_gpio();
 	susp_ambient();
 	susp_buttons();
-
-	wdt_disable();
 }
 
 void power_down()
@@ -76,7 +71,6 @@ int main(void)
 	sei();
 #if 1
 	while (1) {
-		wdt_reset();
 		sleep_mode();
 	}
 #endif
diff --git a/firmware/tmr.c b/firmware/tmr.c
index d53981a..d1f1b23 100644
--- a/firmware/tmr.c
+++ b/firmware/tmr.c
@@ -1,44 +1,29 @@
 #include <avr/io.h>
 #include <avr/interrupt.h>
+#include <avr/wdt.h>
 
 #include "lights.h"
 
 volatile uint16_t jiffies;
-#define PATTERN_DIV 10	// clk/10
-static unsigned char pattern_div;
 
 void init_tmr()
 {
-	TCCR0A = _BV(WGM00);
-	TCCR0B = _BV(CS02) | _BV(CS00); // CLK/1024 = 1 kHz
-	OCR0A = 5; // 200 Hz
-	TIMSK |= _BV(OCIE0A);
-
-	jiffies = 0;
-	pattern_div = PATTERN_DIV;
+	WDTCR = _BV(WDIE) | _BV(WDP1); // interrupt mode, 64 ms
 }
 
 void susp_tmr()
 {
-	TCCR0A = TCCR0B = 0;
-	TIMSK &= ~_BV(OCIE0A);
-	TIFR = 0;
+	wdt_disable();
 }
 
-ISR(TIMER0_COMPA_vect)
-{
+ISR(WDT_vect) {
 	++jiffies;
 
-	pwm_timer();
-
-	if (--pattern_div == 0) {
-		timer_check_buttons();
-		patterns_next_tick();
-		timer_start_slow_adcs();
-		pattern_div = PATTERN_DIV;
-	}
+	timer_check_buttons();
+	patterns_next_tick();
+	timer_start_slow_adcs();
 
-	if ((jiffies & 0x7FFF) == 0)
+	if ((jiffies & 0x7FF) == 0)
 		ambient_log_min_max();
 }
 
-- 
2.39.3