Our custom board cant find HID interface when entering into Serial Downloader mode.After test, we find the root cause is the MX6DL cannot read the boot mode pin correctly. When we set boot mode   , all these boot mode cannot find the HID interface and cannot enter into Serial Downloader mode except the boot mode . Why???
Ok, this is the first problem. And then the second comming, When we boot from fuse,we should blow the fuses. and we need to catch the uart log by MFG tool. After jumping into OS img,the uart log didnt turn up at all.And I need to say, this custom board is on the EVT1 stage, EVT0 can catch the uart log. There is no differences between SW and HW in the aspect of the UART.Why???
So can I assume the MX6DL CPU has some defects from above all these problems ?
Help me 3Q~