I'm working with the AD7768-4FMCZ evaluation board and interfacing it with an STM32H7A3ZI(Nucleo-H7A3ZI-Q). I'm configuring the AD7768 via SPI and have tried using both SAI and SPI peripheral on the STM32 to receive TDM data. I’ve successfully initialized both SPI and SAI with DMA, and I'm trying to set DCLK = MCLK/1. All the channel outputs are set to DOUT0 (FORMAT pin is set to logic 1). However, I’m facing issues interpreting the received data — my samples[] buffer fails to evaluate properly in the debugger, and I’m unsure if the SAI is correctly aligned with the TDM frame. I have tried hooking up the dev board with a logic analyser, the DOUT and DRDY pins are producing patterns similar to one another, even without any inputs to the analog input channels. I have tried using a load cell to verify the behaviour of the pins, but it has been erratic, with none of them matching the datasheet. I have attached the obtained waveforms below, the ones similar to each other are DRDY and DOUT.
I’d appreciate any guidance on how to properly configure the AD7768 for TDM streaming with external DCLK and DRDY, and tips for ensuring correct SAI data alignment on the STM32 side. Any working example or advice would be a huge help.
