HI.
I am currently using the MC33774 to read the voltages of the four AFEs: VAUX, VBAT, VDDC, and VDDA. I send two acquisition commands consecutively with a 10ms interval in between, and then send a read command after a 50ms wait to read the data from the SECM register. However, strangely, although the reads are correct most of the time, there are occasional cases where all the voltage values are very low. Why is this?
Hello Embedded_novice
Good day!
My first suspicion would be that the SECM supply-voltage results are being read before the measurement cycle has completely finished, or that the second acquisition command is restarting the conversion before the first result set is latched. This would explain why all four voltage channels become low together while communication itself remains functional.
- Which acquisition command is being sent exactly?
- Are the AFEs configured in periodic mode?
- Do the low values occur on all four AFEs simultaneously, or only on one device in the daisy chain?
- Can you try increasing the interval between acquisition commands?
I hope this information has helped you, please let me know if you need help with anything else.
Have a great day and best of luck.