UUU Troubleshooting
Board not detected by UUU
1. Verify USB recovery mode
The board must be placed in USB recovery / download mode before UUU can communicate with it. The jumper or DIP switch configuration is board-specific — consult the Hardware Reference Manual.
2. Use the correct USB connector
Engicam boards have a dedicated USB OTG / programming connector. Do not use a standard host USB port — it will not enter recovery mode from there.
3. Check the USB connection
A detected board appears as:
Connected Known USB Devices
Path Chip Pro Vid Pid BcdVersion
====================================================
3:32 MX865 SDPS: 0x1FC9 0x0146 0x0002
If nothing appears:
- Try a different USB cable (short, data-rated).
- Try a different USB port on the host (avoid hubs).
- Run
lsusbto check if the device is visible to the OS at all.
4. Run with sudo
On Linux, UUU requires root privileges to access the USB device:
Alternatively, add a udev rule to grant access without sudo (see UUU documentation).
UUU fails mid-flash
Check the USB cable
A long or low-quality cable can cause USB transfer errors during a several-minute flash operation. Use a cable shorter than 1 m.
Check the power supply
The board must be powered by a stable supply throughout the flash. Do not power it through a USB hub or a laptop port that may throttle current.
Retry from scratch
UUU can be safely re-run. The eMMC will be overwritten from sector 0:
Verbose output for debugging
Run with -v to see the full protocol exchange and identify where it stalls:
Which imx-boot file should I use?
The boot binary must match both the SoC and the DDR configuration of your module. The filename pattern is:
Find it in the Yocto deploy directory:
If your module has multiple DDR variants (1 GB / 2 GB / 4 GB), make sure the binary was built with the correct UBOOT_CONFIG. See DDR Selection.
Pass it as the first argument to UUU: