ADC Clock

Hello,

I am making a peak detector, and want to feed its signal into the Appolo 3 MCU ADC. It would be great if I could sync the peak detector reset pin with the ADC, so that whenever the ADC takes a sample it reads the latest peak.

Question is, can I somehow bring the ADC clock out to a GPIO pin? I.e, if the clock signal is high, the GPIO pin is high and when the clock is low, the GPIO pin is low.

Thanks.

  1. When performing an analogRead() it is a ONE-shot occurrence to read the ADC. Not sure how precise you want to get it/ need it, but the set a GPIO output HIGH, JUST before the analogRead(), might be enough.

  2. if you need to get it 100% aligned, the ADC clock in the Sparkfun Library is the HRFC (so 48Mhz). According to the datasheet, this signal is not available on a GPIO. There are different clock sources that can be made available with CLKOUT, HFRC is not part of that.