From 3bcb08de8d212ef69f472d0d1de6eda446d07e75 Mon Sep 17 00:00:00 2001
From: Paul Goeser <paul@rakka.de>
Date: Sun, 24 Feb 2013 19:35:11 +0100
Subject: [PATCH] streamlined pwm-code

---
 firmware/cup.c | 40 +++++++++++++++++++++++++---------------
 1 file changed, 25 insertions(+), 15 deletions(-)

diff --git a/firmware/cup.c b/firmware/cup.c
index 0fff87a..69a4908 100644
--- a/firmware/cup.c
+++ b/firmware/cup.c
@@ -23,18 +23,18 @@ uint8_t setting_timeout = 0;
 
 uint8_t adc_pos = 0;
 uint16_t adc_sum = 0;
-uint16_t target = 0;
 
-uint16_t temperature = 0;
+uint16_t target = 0;
+uint16_t temperature = 0; // all temperatures are in tenth of degrees celsius
 
-uint8_t heat_output = 0;
 
-uint8_t heat_pwm = 0;
-uint8_t heat_on[2] = {0, 128};
-uint8_t heat_off[2] = {128, 0};
+uint8_t heat_pwm = 0; // softpwm counter
+uint8_t heat_power = 0; // requested heating power; 0..255
+//uint8_t heat_on[2] = {0, 128};
+//uint8_t heat_off[2] = {128, 0};
 
 uint8_t input_state = 0;
-uint8_t dev_state = 0;
+uint8_t dev_state = 0; // whether the device is on or off
 
 #define TEN_SECONDS 256
 uint16_t startup = TEN_SECONDS;
@@ -62,10 +62,24 @@ ISR(TIM1_OVF_vect)
 	
 	/* incremtening softpwm, toggling output if needed */
 	heat_pwm++;
-	if(heat_pwm == heat_on[0]) {PORTB |= (1 << FET0_PIN);}
+    if(heat_pwm <= heat_power)
+    {   
+        PORTB |= (1 << FET0_PIN);  
+    } else {
+        PORTB &= ~(1 << FET0_PIN);
+    }
+    if( ((heat_pwm + 128)&0xff) <= heat_power )
+    {   
+        PORTB |= (1 << FET1_PIN);  
+    } else {
+        PORTB &= ~(1 << FET1_PIN);
+    }
+    
+/*	if(heat_pwm == heat_on[0]) {PORTB |= (1 << FET0_PIN);}
 	if(heat_pwm == heat_off[0]) {PORTB &= ~(1 << FET0_PIN);}
 	if(heat_pwm == heat_on[1]) {PORTB |= (1 << FET1_PIN);}
 	if(heat_pwm == heat_off[1]) {PORTB &= ~(1 << FET1_PIN);}
+    */
 }
 
 ISR(PCINT0_vect)
@@ -249,16 +263,12 @@ int main(void)
 				adc_pos = 0;
 				if(1)//dev_state)
 				{
-					heat_output = control_output();
-					if(startup && heat_output > 96) {heat_output = 96;}
-					heat_on[0] = 0;
-					heat_on[1] = 128;
-					heat_off[0] = heat_output;
-					heat_off[1] = heat_output + 128;
+					heat_power = control_output();
+					if(startup && heat_power > 96) {heat_power = 96;}
 				}
 				/*else
 				{
-					heat_on[0] = heat_on[1] = heat_off[0] = heat_off[1] = 0;
+                    heat_power = 0;
 				}*/
 			}
 		}