Colibri T30 in Iris board with WEC7 trying to flash uboot and Linux Yocto but freezes before uboot prompt presented

Basically followed the instructions for Flashing u-boot to Colibri running WEC7 but each time we put the device into recovery mode (ie type “reboot rcm”) at eboot menu on debug port and then connect the USB cable to our Linux Ubuntu PC and use “./ -d” the u-boot freezes at “*** Warning - bad CRC, using default environment” and proceeds no further.

Any suggestions. We have a Viola plus board but not sure if we can access the debug serial port to try a different module.


Could you please tell which exactly Linux image you are truing to flash? Also text logs from your Ubuntu terminal where you run ./ -d and from Colibri debug UART would be helpfull.

Linux image is Linux LXDE Image Colibri T30 2.8.7

Output from Ubuntu 18.04 terminal:

osboxes@osboxes:~$ sudo ./ -d

Colibri T30 rootfs detected

bct file: …/colibri-t30_bin/colibri_t30_12MHz_NT5CC256M16CP-DI_400MHz.bct

bootloader file: …/colibri-t30_bin/u-boot-dtb-tegra.bin

load addr 0x80108000

entry addr 0x80108000

device id: 0x7030

uid: 0x015c3e602453ee09

RCM version: 3.1

downloading miniloader to target at address 0x4000a000 (128916 bytes)…

miniloader downloaded successfully

Chip UID: 0x0000000000000000015c3e602453ee09

Chip ID: 0x30

Chip ID Major Version: 0x1

Chip ID Minor Version: 0x3

Chip SKU: 0xb0 (t30)

Boot ROM Version: 0x1

Boot Device: 0x2 (EMMC)

Operating Mode: 0x3 (developer mode)

Device Config Strap: 0x0

Device Config Fuse: 0x0

SDRAM Config Strap: 0x0

sending file: …/colibri-t30_bin/colibri_t30_12MHz_NT5CC256M16CP-DI_400MHz.bct

  • 6128/6128 bytes sent

…/colibri-t30_bin/colibri_t30_12MHz_NT5CC256M16CP-DI_400MHz.bct sent successfully

sending file: …/colibri-t30_bin/u-boot-dtb-tegra.bin

/ 517214/517214 bytes sent

…/colibri-t30_bin/u-boot-dtb-tegra.bin sent successfully

Output from colibri debug UART:

Toradex Bootloader 2.2 for Tegra Built Dec 7 2018 15:05:43

Press [SPACE] to enter Bootloader Menu

Colibri T30 1GB IT 1.1B Serial: 6624748

RAM: 1024 MB, CarveOut: 2 MB

Locating kernel image in flash…Done(620)

Decompressing IMAGE(26353307, 51248212) from FLASH(0) to RAM(80016000)…Done(482ms)

Jumping to image at 0x80016000…

ðToradex Bootloader 2.2 for Tegra Built Dec 7 2018 15:05:43

Press [SPACE] to enter Bootloader Menu

BootLoader Configuration:

C) Clear Flash Registry

X) Enter CommandPrompt Mode

D) Download image to RAM now

F) Download image to FLASH now

L) Launch existing flash resident image now

Enter your selection: x

reboot rcm


U-Boot SPL 2016.11-2.8.7+g5c2d46b325 (Jun 10 2020 - 17:22:21)

Trying to boot from RAM

U-Boot 2016.11-2.8.7+g5c2d46b325 (Jun 10 2020 - 17:22:21 +0000)

SoC: tegra30

Reset cause: POR


MMC: Tegra SD/MMC: 0, Tegra SD/MMC: 1

*** Warning - bad CRC, using default environment

We solved the issue by shorting the 2 pins on the Iris board to put the module into recovery mode and then using command prompt and NVFlash.exe to send the u-boot.bin file across USB.
Using the other method of pressing SpaceBar on the UART debug port doesn’t work anymore even though we have been using that method for years.

Looks like our WinCE folks might have changed the eMMC configuration which is what seems to be causing this issue.