We made an imx board with reference to the official 8MMINILPD4-EVK board. The DDR, emmc and circuit are the same.
Get the board, we try to burn the code in the serial downloader mode, the burning is successful, the attachment is the print log!
But the strange thing is that we switched to the internal boot mode, the serial port did not print any more, we checked the boot0 and boot1 pins, their levels are normal, we also found that the board has become the serial downloader mode!
And in other modes, it will eventually become the serial downloader mode!
Excuse me, what kind of problem might there be? How can I locate the problem?
We have confirmed that the level of the boot pin is normal.
We did a similar imx8m-mini board before，we have added some peripheral circuits in new board, but the core circuits (emmc and ddr) are the same!That old board works fine,so we use its image!
We are puzzled that there is no printout in the internal boot mode, and it eventually enters the serial downloader mode,why?
There is no printout, we can't know what happened in the internal boot mode!
Excuse me, is there any debugging method to to see the process information of the internal boot mode?