FastPWM
Fork of FastPWM by
Device/FastPWM_LPC_SCT.cpp
- Committer:
- Sissors
- Date:
- 2016-03-14
- Revision:
- 30:87e38b846651
- Parent:
- 29:3e4d3b900850
File content as of revision 30:87e38b846651:
//For targets which use the SCT #if defined(TARGET_LPC81X) || defined(TARGET_LPC82X) #ifdef TARGET_LPC82X #define CTRL_U CTRL #endif #include "FastPWM.h" void FastPWM::initFastPWM( void ) { //Mbed uses the timer as a single unified 32-bit timer, who are we to argue with this, and it is easier bits = 32; #ifdef TARGET_LPC82X //The mbed lib uses the PWM peripheral slightly different, which is irritating. This sets it bck to the LPC81X _pwm.pwm->EVENT[_pwm.pwm_ch + 1].CTRL = (1 << 12) | (_pwm.pwm_ch + 1); // Event_n on Match_n _pwm.pwm->EVENT[_pwm.pwm_ch + 1].STATE = 0xFFFFFFFF; // All states _pwm.pwm->OUT[_pwm.pwm_ch].SET = (1 << 0); // All PWM channels are SET on Event_0 _pwm.pwm->OUT[_pwm.pwm_ch].CLR = (1 << (_pwm.pwm_ch + 1)); // PWM ch is CLRed on Event_(ch+1) #endif //With 32-bit we fix prescaler to 1 _pwm.pwm->CTRL_U |= (1 << 2) | (1 << 3); _pwm.pwm->CTRL_U &= ~(0x7F << 5); _pwm.pwm->CTRL_U &= ~(1 << 2); } void FastPWM::pulsewidth_ticks( uint32_t ticks ) { #ifdef TARGET_LPC81X _pwm.pwm->MATCHREL[_pwm.pwm_ch + 1].U = ticks; #else _pwm.pwm->MATCHREL[_pwm.pwm_ch + 1] = ticks; #endif } void FastPWM::period_ticks( uint32_t ticks ) { #ifdef TARGET_LPC81X _pwm.pwm->MATCHREL[0].U = ticks; #else _pwm.pwm->MATCHREL[0] = ticks; #endif } uint32_t FastPWM::getPeriod( void ) { #ifdef TARGET_LPC81X return _pwm.pwm->MATCHREL[0].U; #else return _pwm.pwm->MATCHREL[0]; #endif } //Maybe implemented later, but needing to change the prescaler for a 32-bit //timer used in PWM mode is kinda unlikely. //If you really need to do it, rejoice, you can make it run so slow a period is over 40,000 year uint32_t FastPWM::setPrescaler(uint32_t reqScale) { //Disable dynamic prescaling dynamicPrescaler = false; return 1; } #endif