I am using the msp430fg4618 chip to convert the peak of pulse heights. I have it setup where the ADC12 is triggered by the Timer_A.OUT1. The Timer_A is sourced externally by a circuit controlled by the incoming pulses. So the timer only counts up when a pulse is received. I only have the timer counting up to 1 in Set/Reset mode. After the conversion, inside the ADC12 interrupt, if TAR=1, I send a dummy pulse to the TACLK pin to reset it to 0. The setup works great and exactly like it should when testing with a stable frequency of pulses. But the actual instruments I am building this for have pulses that occur randomly, and sometimes they can be really close together.
What I was wanting to know is if the ADC sample and conversion has started, and I receive several pulses during that time which then request another sample and conversion (setting the ADC12TOV bit), what does the ADC12 do when the current conversion is completed? Does it go ahead and start a second conversion? Or does it ignore it and wait for another trigger?
I was assuming from everything I read, it would be ignored and when I read and reset the MEM IFGs that ADC12TOV bit would be reset.
One thing I noticed when measuring the Timer output with the oscilloscope was that occasionally the output would get reversed. Normally it would only be high for about 11us which is the time it takes to sample, convert, and get into the interrupt where I set it low again. But occasionally, it would be reversed where the output would be high and then go low for 11us before going high again.
I wasn't sure if this was due to the ADC or the Timer.