Use timer 4 instead of 3 for systick (1ms).

2 files changed, 10 insertions, 27 deletions

diff --git a/avr/main.c b/avr/main.c
index 2199454..0a1cab6 100644
--- a/avr/main.c
+++ b/avr/main.c
@@ -115,10 +115,10 @@ void setup_avr(void)
 	CLKPR = 0;
 
 	/* Timer */
-	PRR1 &= ~_BV(PRTIM3);
-	OCR3A = F_CPU / 1000 - 1;	/* Timer3: 1000Hz interval (OC3A) */
-	TCCR3B = (0b01<<WGM32)|(0b001<<CS30); /* CTC Mode, Prescaler 1 */
-	TIMSK3 = _BV(OCIE3A);		/* Enable TC2.oca interrupt */
+	PRR1 &= ~_BV(PRTIM4);
+	OCR4A = F_CPU / 1000 - 1;	/* Timer4: 1000Hz interval */
+	TCCR4B = (0b00<<WGM42)|(0b001<<CS40); /* Normal Mode, Prescaler 1 */
+	TIMSK4 = _BV(OCIE4A);		/* Enable Output Compare A interrupt */
 
 	/* INT5, INT6: falling edge */
 	EICRB = (EICRB & ~((0b11 << ISC50) | (0b11 << ISC60))) |
diff --git a/avr/timer.c b/avr/timer.c
index f45f267..1b15985 100644
--- a/avr/timer.c
+++ b/avr/timer.c
@@ -1,14 +1,13 @@
 /*
  * (C) Copyright 2014 Leo C. <erbl259-lmu@yahoo.de>
  *
- * SPDX-License-Identifier:	GPL-2.0+
+ * SPDX-License-Identifier:	GPL-2.0
  */
 
-#include "common.h"
+#include "timer.h"
 #include <avr/interrupt.h>
 #include <util/atomic.h>
 #include "time.h"
-#include "timer.h"
 
 /* timer interrupt/overflow counter */
 /* counts up every ms. */
@@ -16,9 +15,9 @@ static volatile
 uint32_t timestamp;
 
 /*
- * 1000Hz timer interrupt generated by OC3A
+ * 1000Hz timer interrupt generated by OC4A
  */
-ISR(TIMER3_COMPA_vect)
+ISR(TIMER4_COMPA_vect)
 {
 	static int_fast8_t tick_10ms;
 	static int_fast8_t tick_1s;
@@ -26,6 +25,8 @@ ISR(TIMER3_COMPA_vect)
 
 	extern void disk_timerproc(void);
 
+	OCR4A += F_CPU / 1000;	/* 1000Hz interval */
+
 	timestamp++;
 
 	i = tick_10ms + 1;
@@ -49,24 +50,6 @@ ISR(TIMER3_COMPA_vect)
 
 /*--------------------------------------------------------------------------*/
 
-#if 0
-void timer_setup(void)
-{
-
-	/* Clock */
-	CLKPR = _BV(CLKPCE);
-	CLKPR = 0;
-
-	/* Timer */
-
-	OCR1A = F_CPU / 1000 - 1; // Timer1: 1000Hz interval (OC1A)
-	TCCR1B = 0b00001001;
-	TIMSK1 = _BV(OCIE1A); // Enable TC1.oca interrupt
-}
-#endif
-
-/*--------------------------------------------------------------------------*/
-
 uint32_t get_timer(uint32_t base)
 {
 	uint32_t ret;