Posted on May 17, 2011 at 13:44Hi Brian.
I'm not using ST Libraries, just using directly the registers.
I've compared some ST code examples and also that commands you just sent and I think everything is ok, my code and ST Libraries are doing the same thing. When I debug with IAR and inspect STM registers, everything is ok too.
As you mentioned, ADC is working properly and seems to me that the unique difference when triggering ADC by software or external sources is the EXTSEL field in ADC_CR2 register... So I suspect my error is on TIM1configuration, precisely on event generation that should trigger ADC.
Below the most important pieces of my code:
//######### Timer Configuration #########
RCC_APB2ENR->TIM1EN = 1; //enable timer clock
TIM1_CR1->CEN = 0; //disable counter
TIM1_CR1->ARPE = 1; //auto reload
TIM1_PSC = 500; //Timer prescaler. clk = 10KHz
TIM1_ARR = 0xFFFF;
TIM1_CNT = 0xFFFF;
//Configure channel
TIM1_CCMR1->CC1S = 2; //IC1 mapped to CH2
TIM1_CCMR1->IC1PSC = 0; //No prescaler
TIM1_CCMR1->IC1F = 0; //No filter
TIM1_CCER->CC1P = 0; //active on rising edge
//Configure channel
TIM1_CCMR1->CC2S = 1; //IC1 mapped to CH2
TIM1_CCMR1->IC2PSC = 0; //No prescaler
TIM1_CCMR1->IC2F = 0; //No filter
TIM1_CCER->CC2P = 1; //active on falling edge
//Timer mode - PWM Input Capture
TIM1_SMCR->TS = 6; //trigger input
TIM1_SMCR->SMS = 4; //slave mode reset
//Enable captures
TIM1_CCER->CC1E = 1;
TIM1_CCER->CC2E = 1;
//Configure interruptions and DMA
TIM1_DIER->CC2DE = 1; //CC2 DMA request enabled
As you suggested I enabled MOE bit, but I didn't understand why
this is needed. I'm using Input PWM mode and it seems to deal with
outputs. Sorry if I'm wrong. Anyway I tested with it and got no trigger.
TIM1_BDTR->MOE = 1;
//Enable timer
TIM1_CR1->CEN = 1;
Thanks a lot for your attention.
Best regards.
