I'm trying to do a first run on our carrier boards with PCM052 installed.
I then configured the SOM in the Phytec development board to boot from NAND flash it boots properly.
When I place this SOM in our carrier board, it does not boot no traffic is seen in the RS232 TX or RX pins.
What the team observed on the TX line of the RS232 we see +6 rather than -6 as we would expect(this is what we observed in the Phytec development board), we see no outputs.
We have checked the reset sequence. The external reset signal goes high about 25ms after power is applied. Signals look clean.
The 3.3V for the SOM looks good. The 24MHz oscillator is running.
The signal level look the same as when it is running in the Phytec development board.
- Are there any test points to check to determine the SOM is properly booted aside from RS232?
- What needs to be check that might help me debug the issue.
- What other means to check the bootloader is loaded and booted correctly.
Any help and advise would be greatly appreciated.