Sampling ADC data

[marco3]

Posted on October 04, 2016 at 19:55

I'm trying to get data from an ADC7689,  using SPI. I have a NUCLEO STM31F411RE and the code is running on SW4STM32.

My problem is that when I send addresses, all I get is 0xFF, instead of the values the ADC converts.

What could be the cause of this problem? I'm pretty sure the configuration of the registers is correct.

Thanks

Marc

#adc #spi #stm32

[Tesla DeLorean]

Posted on October 04, 2016 at 20:28

You'd perhaps want to review the signals on the wire with a scope or logic-analyzer in the context of the data-sheet and confirm if the ADC is actually sending data, and that the STM32 is accurately reporting what it is seeing.

http://www.analog.com/media/en/technical-documentation/data-sheets/AD7682_7689.pdf

It could be wired up or powered incorrectly.

The SPI bus or peripheral might not be correctly configured.

The data you have provided is not adequate to be able to remotely diagnose the problem. Restate the problem with clarity, showing how everything is wired and powered, and the software that is configuring and communicating with the device.