Tool/software:
Dear TI experts,
We are currently evaluating the possibility to continuously read 2 ADCs, connected over McSPI to an AM6442 chip:
The initial intention was to use a BCDMA + PDMA combination, triggered by a PWM signal generated from DMTIMER0. Unfortunately, this approach presented two key issues:
- We successfully configured the BCDMA (TX) + PDMA (TX) combination, allowing ADC readout. However, we were unable to trigger the transfer from DMTIMER0, despite correctly routing the PWM signal through the TimeSync Router and properly setting up the DMA trigger.
- Even if we manage to trigger BCDMA using the PWM output, we still cannot precisely set the timer to the desired frequency. This limitation arises because the timer operates on a 25 MHz clock with only a simple prescaler.
Our current hope is to use the PRU to actively trigger the BCDMA TX channel, as it allows us to achieve a constant and controllable frequency. While we understand this method introduces some delay, as long as the delay is deterministic, it should not pose a problem.
So here the actual Question:
What is the correct method to trigger a configured BCDMA channel from the PRU side?
Thanks and regards,
Angel
