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add constants for prescaler values

This commit is contained in:
Bruno Bousquet 2019-07-19 16:16:32 -04:00
parent 7b6f5b5cff
commit 0dede83883
1 changed files with 12 additions and 6 deletions
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18
speeduino/board_avr2560.ino
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@ -3,6 +3,13 @@
#include "globals.h"
#include "auxiliaries.h"
// Prescaler values for timers 1-3-4-5. Refer to www.instructables.com/files/orig/F3T/TIKL/H3WSA4V7/F3TTIKLH3WSA4V7.jpg
const uint8_t TIMER_PRESCALER_1 = ((0<<CS12)|(0<<CS11)|(1<<CS10));
const uint8_t TIMER_PRESCALER_8 = ((0<<CS12)|(1<<CS11)|(0<<CS10));
const uint8_t TIMER_PRESCALER_64 = ((0<<CS12)|(1<<CS11)|(1<<CS10));
const uint8_t TIMER_PRESCALER_256 = ((1<<CS12)|(0<<CS11)|(0<<CS10));
const uint8_t TIMER_PRESCALER_1024 = ((1<<CS12)|(0<<CS11)|(1<<CS10));
void initBoard()
{
/*
@ -19,7 +26,7 @@ void initBoard()
TCCR1B = 0x00; //Disbale Timer1 while we set it up
TCNT1 = 0; //Reset Timer Count
TCCR1A = 0x00; //Timer1 Control Reg A: Wave Gen Mode normal (Simply counts up from 0 to 65535 (16-bit int)
TCCR1B = (1 << CS12); //Timer1 Control Reg B: Timer Prescaler set to 256. 1 tick = 16uS. Refer to www.instructables.com/files/orig/F3T/TIKL/H3WSA4V7/F3TTIKLH3WSA4V7.jpg
TCCR1B = TIMER_PRESCALER_256; //Timer1 Control Reg B: Timer Prescaler set to 256. 1 tick = 16uS.
TIFR1 = (1 << OCF1A) | (1<<OCF1B) | (1<<OCF1C) | (1<<TOV1) | (1<<ICF1); //Clear the compare flags, overflow flag and external input flag bits
boost_pwm_max_count = 1000000L / (16 * configPage6.boostFreq * 2); //Converts the frequency in Hz to the number of ticks (at 16uS) it takes to complete 1 cycle. The x2 is there because the frequency is stored at half value (in a byte) to allow freqneucies up to 511Hz
@ -35,8 +42,7 @@ void initBoard()
TIMSK2 = 0x01; //Timer2 Set Overflow Interrupt enabled.
TCCR2A = 0x00; //Timer2 Control Reg A: Wave Gen Mode normal
/* Now configure the prescaler to CPU clock divided by 128 = 125Khz */
TCCR2B |= (1<<CS22) | (1<<CS20); // Set bits
TCCR2B &= ~(1<<CS21); // Clear bit. Shouldn't be needed as initial value is 0 anyway, but best to play it safe
TCCR2B = (1<<CS22) | (1<<CS20); // Set bits. This timer uses different prescaler values, thus we cannot use the defines above.
TIFR2 = (1 << OCF2A) | (1<<OCF2B) | (1<<TOV2); //Clear the compare flag bits and overflow flag bit
//Enable the watchdog timer for 2 second resets (Good reference: www.tushev.org/articles/arduino/5/arduino-and-watchdog-timer)
@ -52,14 +58,14 @@ void initBoard()
TCCR3B = 0x00; //Disable Timer3 while we set it up
TCNT3 = 0; //Reset Timer Count
TCCR3A = 0x00; //Timer3 Control Reg A: Wave Gen Mode normal
TCCR3B = (1 << CS11) | (1 << CS10); //Same as: 0x03. Timer3 Control Reg B: Timer Prescaler set to 256. Refer to www.instructables.com/files/orig/F3T/TIKL/H3WSA4V7/F3TTIKLH3WSA4V7.jpg
TCCR3B = TIMER_PRESCALER_64; //Timer3 Control Reg B: Timer Prescaler set to 64.
TIFR3 = (1 << OCF3A) | (1<<OCF3B) | (1<<OCF3C) | (1<<TOV3) | (1<<ICF3); //Clear the compare flags, overflow flag and external input flag bits
//Ignition Schedules, which uses timer 5. This is also used by the fast version of micros(). If the speed of this timer is changed from 4uS ticks, that MUST be changed as well. See globals.h and timers.ino
TCCR5B = 0x00; //Disable Timer5 while we set it up
TCNT5 = 0; //Reset Timer Count
TCCR5A = 0x00; //Timer5 Control Reg A: Wave Gen Mode normal
TCCR5B = (1 << CS11) | (1 << CS10); //Timer5 Control Reg B: Timer Prescaler set to 64. Refer to www.instructables.com/files/orig/F3T/TIKL/H3WSA4V7/F3TTIKLH3WSA4V7.jpg
TCCR5B = TIMER_PRESCALER_64; //Timer5 Control Reg B: Timer Prescaler set to 64.
TIFR5 = (1 << OCF5A) | (1<<OCF5B) | (1<<OCF5C) | (1<<TOV5) | (1<<ICF5); //Clear the compare flags, overflow flag and external input flag bits
#if defined(TIMER5_MICROS)
@ -71,7 +77,7 @@ void initBoard()
TCCR4B = 0x00; //Disable Timer4 while we set it up
TCNT4 = 0; //Reset Timer Count
TCCR4A = 0x00; //Timer4 Control Reg A: Wave Gen Mode normal
TCCR4B = (1 << CS11) | (1 << CS10); //Timer4 Control Reg B: aka Divisor = 256 = 122.5HzTimer Prescaler set to 256. Refer to www.instructables.com/files/orig/F3T/TIKL/H3WSA4V7/F3TTIKLH3WSA4V7.jpg
TCCR4B = TIMER_PRESCALER_64; //Timer4 Control Reg B: Timer Prescaler set to 64.
TIFR4 = (1 << OCF4A) | (1<<OCF4B) | (1<<OCF4C) | (1<<TOV4) | (1<<ICF4); //Clear the compare flags, overflow flag and external input flag bits
}