SparkFun Forums

[pcbGuru]

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.

[paulvha]

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.