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Merge pull request #1653 from XPila/MK3

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Phase correct PWM for bed, frequency 40KHz.
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PavelSindler 2019-03-27 21:07:15 +01:00 committed by GitHub
commit c1da07bda0
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1 changed files with 9 additions and 18 deletions
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27
Firmware/timer02.c
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@ -11,19 +11,11 @@
uint8_t timer02_pwm0 = 0;
void timer02_set_pwm0(uint8_t pwm0)
{
if (timer02_pwm0 == pwm0) return;
if (pwm0)
{
TCCR0A |= (2 << COM0B0);
OCR0B = pwm0 - 1;
}
else
{
TCCR0A &= ~(2 << COM0B0);
OCR0B = 0;
}
TCCR0A |= (2 << COM0B0); //switch OC0B to OCR mode
OCR0B = (uint16_t)OCR0A * pwm0 / 255;
timer02_pwm0 = pwm0;
}
@ -39,13 +31,12 @@ void timer02_init(void)
TIMSK0 &= ~(1<<OCIE0B);
//setup timer0
TCCR0A = 0x00; //COM_A-B=00, WGM_0-1=00
TCCR0B = (1 << CS00); //WGM_2=0, CS_0-2=011
//switch timer0 to fast pwm mode
TCCR0A |= (3 << WGM00); //WGM_0-1=11
//set OCR0B register to zero
OCR0B = 0;
//disable OCR0B output (will be enabled in timer02_set_pwm0)
TCCR0A &= ~(2 << COM0B0);
OCR0A = 200; //max PWM value (freq = 40kHz)
OCR0B = 0; //current PWM value
//switch timer0 to mode 5 (Phase Correct PWM)
TCCR0A |= (1 << WGM00); //WGM_0-1=01
TCCR0B = (1 << CS00) | (1 << WGM02); //WGM_2=1, CS_0-2=001 (no prescaling)
TCCR0A |= (2 << COM0B0); //switch OC0B to OCR mode
//setup timer2
TCCR2A = 0x00; //COM_A-B=00, WGM_0-1=00
TCCR2B = (4 << CS20); //WGM_2=0, CS_0-2=011