The following table lists the U-Boot file associated with each ConnectCore 6UL variant:

RAM size SBC board U-Boot file U-Boot defconfig

1GB

SBC Express

u-boot-ccimx6ulstarter1GB-2020.04-r0.imx

ccimx6ulstarter1GB_defconfig

SBC Pro

u-boot-ccimx6ulsbc1GB-2020.04-r0.imx

ccimx6ulsbc1GB_defconfig

512MB

SBC Express

u-boot-ccimx6ulstarter512MB-2020.04-r0.imx

ccimx6ulstarter512MB_defconfig

SBC Pro

u-boot-ccimx6ulsbc512MB-2020.04-r0.imx

ccimx6ulsbc512MB_defconfig

256MB

SBC Express

u-boot-ccimx6ulstarter-2020.04-r0.imx

ccimx6ulstarter_defconfig

SBC Pro

u-boot-ccimx6ulsbc-2020.04-r0.imx

ccimx6ulsbc_defconfig

Check your variant RAM size on the serial console boot log:

U-Boot dub-2020.04-r6.1 (Sep 19 2023 - 07:12:31 +0000)

CPU:   i.MX6UL rev1.2 528 MHz (running at 396 MHz)
CPU:   Industrial temperature grade (-40C to 105C) at 32C
Reset cause: POR
I2C:   ready
DRAM:  256 MiB
MCA:   HW_VER=1  FW_VER=1.19
PMIC:  PFUZE3000 DEV_ID=0x30 REV_ID=0x11
NAND:  256 MiB
MMC:   FSL_SDHC: 0
In:    serial
Out:   serial
Err:   serial
Model: Digi International ConnectCore 6UL SBC.
ConnectCore 6UL SOM variant 0x06: Industrial Ultralite 528MHz, 256MB NAND, 256MB DDR3, -40/+85C, Wireless, Bluetooth
  Board version 3, ID 135
Boot device:  NAND
Net:   FEC0 [PRIME]
Fastboot: Normal
Normal Boot
Hit any key to stop autoboot:  0
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