2021-12-08 04:46 AM
Hello,
I have design power monitor section using STPM33.
I have taken its reference from STPM33 EVK board and its datasheet.
I have attached our design schematic. Sensing the current with the shunt resisters.
Below are Test point voltages for debug:
VREF1-17 - 1.15 V
VREF2-19 - 1.15 V
VDDA-21 - 2.85 V
EN-8 - 3.30 V
VCC-23 - 3.30 V
VDDD-27 - 1.21 V
SYN-28 - 3.26 V
SCS-29 - 3.30 V
All pin status seems correct as shown above.
I am trying to read/write the registers using UART. but STPM33 is not giving any response.
There is no activity on STPM TX pin. it is always High.
I am using example code from STM for testing. Link
I also have EVALSTPM33.
I had tested the STPM33 example code on this EVK with the connection of our actual MCU and with the actual UART connection shown in the attached file.
I was working fine.
I am doing the same with onboard STPM33.
MCU is sending some data on the RX line but STPM33 is not responding on TX. it is always high.
I am doubting that the STPM is not going into UART mode.
Let me know if you have other suspects where I can look?
Is there any issue with configuration and selection?