I am working on a design with the IMX7ULP. By default BOOTMODE_1 and BOOTMODE_0 are pulled down to ground so the boot type is Boot from Fuses. After the eMMC is flashed I want to get this to Serial Download mode so I can update the image. So when I change BOOTMODE_1 and BOOTMODE_1 to 01 it never enters Serial Download mode. It looks like it is hanging somewhere. When change the bootmode pins back to 00 the device starts booting from the eMMC. Can someone help me figure out what is going wrong?
pls check the BT_FUSE_SEL bit, refer to the Table 35-4. i.MX 7ULP boot modes of reference manual, Boot Configuration is loaded from fuse instead of boot configuration pins. If BT_FUSE_SEL=0, boot flow will jump to Serial Downloader.
