We have the ADS8332 set to manual mode to cycle through and read all 8 channels. It works for a while but ultimately the CFR gets reset back to 0xFFF. The first shot is transaction N where we perform a conversion and read each of the 8 channels (this is working). The next shot is transaction N+1 where we perform a conversion and again read all 8 channels. I've written test code to transmit a 0xC000 to the ADS8332 so we can query the CFR. You can see in transaction N the CFR is 0x7ED as expected but then in transaction N+1 the CRF is reset back to 0xFFF.
I have written code to toggle an I/O pin (Scope Trigger in image above) when a 0xFFF is read back from CRF. I have a scope also triggering on this same I/O (yellow, below) and I've measured the RESET (green, below), VA (purple, below), & VBD (blue, below) lines:
Can you please provide insight as to what would cause the CFR to reset back to 0xFFF? Per the TI spec sheet I found the following but none of these appear to be the cause: