I've designed a custom carrier board to be used with CM3, and it worked to flash the EMMC the first time, no problems.
The boot circuit is the same as the CMIO.
Now I would like to erase the flash and load other image, but when I set the jumper to enable the USB boot, same as if doing in the CMIO, the PC don't detect the device, and the CM3 boot normally. Even if I force the emmc_disable_n to GND by connecting it directly, I can't get the board detected by USB.
My host machine is Window 10, I don't think this is a problem, since I flashed the board in the same PC the first time.
Does anyone have this issue?