Step 3: Program the Yocto firmware
The ConnectCore 6UL is shipped without a default operating system loaded. Only U-Boot is flashed in the device. This step demonstrates how to install Yocto in your ConnectCore 6UL.
1. Establish a serial connection with your device
Before you start programming the firmware, you must open a serial connection with the device. You can use any serial terminal program such as Tera Term, Minicom, CoolTerm, or HyperTerminal.
CAUTION! Due to an incompatibility between the USB/serial driver and the PuTTY terminal program, you must use another serial terminal program such as Tera Term, Minicom, CoolTerm, or HyperTerminal.
Open a serial connection with the following settings:
- Port: Serial port where ConnectCore 6UL is connected
- Baud rate: 115200
- Data bits: 8
- Parity: None
- Stop bits: 1
- Flow control: None
2. Program the firmware
Once you have established the serial connection, you can start the firmware update process. Follow these steps to install Yocto in the device:
- Download the firmware images from this location: ftp://ftp1.digi.com/support/digiembeddedyocto/2.0/r5/images/82004060_A.zip
- Decompress 82004060_A.zip.
-
Place the decompressed files in the root of a FAT-formatted microSD card and insert it in the microSD socket of the ConnectCore 6UL SBC Pro (bottom side).
-
Reset the device by pressing the reset button on the board and immediately press any key in the serial terminal to stop the auto-boot process. The U-Boot bootloader prompt displays:
U-Boot dub-2015.04-r5.4 (Nov 14 2016 - 13:06:52) CPU: Freescale i.MX6UL rev1.1 528 MHz (running at 396 MHz) CPU: Industrial temperature grade (-40C to 105C) at 44C Reset cause: POR I2C: ready DRAM: 256 MiB MCA: HW_VER=1 FW_VER=0.12 PMIC: PFUZE300 DEV_ID=0x30 REV_ID=0x11 NAND: 256 MiB MMC: FSL_SDHC: 0 In: serial Out: serial Err: serial ConnectCore 6UL SOM variant 0x02: Industrial Ultralite 528MHz, 256MB NAND, 256MB DDR3, -40/+85C, Wireleh Board: ConnectCore 6UL SBC, version 2, ID 135 Net: FEC0 Hit any key to stop autoboot: 0
Note If you do not immediately press any key, the U-Boot auto-boot process tries to read the Linux firmware from the NAND flash. Because there is no firmware pre-programmed in the kit, you will see some expected error messages. The next step explains how to program the Linux firmware inside the NAND flash.
- Install the firmware into the NAND, executing the following command:
=> run install_linux_fw_sd
Once the firmware is installed, the device boots automatically.
Note During installation, error messages appear when the installation process attempts to override MAC addresses. These messages are expected.

## Resetting to default environment oldval: 00:40:9D:7D:17:9A defval: 00:04:f3:ff:ff:fa ## Error: Can't overwrite "ethaddr" himport_r: can't insert "ethaddr=00:04:f3:ff:ff:fa" into hash table oldval: 00:40:9D:7D:17:9B defval: 00:04:f3:ff:ff:fb ## Error: Can't overwrite "eth1addr" himport_r: can't insert "eth1addr=00:04:f3:ff:ff:fb" into hash table oldval: 00:40:9D:7D:17:9C defval: 00:04:f3:ff:ff:fc ## Error: Can't overwrite "wlanaddr" himport_r: can't insert "wlanaddr=00:04:f3:ff:ff:fc" into hash table oldval: 00:40:9D:7D:17:9D defval: 00:04:f3:ff:ff:fd ## Error: Can't overwrite "btaddr" himport_r: can't insert "btaddr=00:04:f3:ff:ff:fd" into hash table