The ConnectCore 6 Plus platform uses U-Boot (Universal Bootloader) as primary bootloader. U-Boot is an open-source project. You can find standard documentation about commands, environment variables, Flattened Device Tree support, and more at www.denx.de/wiki/U-Boot/Documentation.
About this guide
This guide only describes specific changes made to the standard U-Boot by Digi International.
U-Boot for ConnectCore 6 Plus is based on standard U-Boot v2017.03 plus NXP patches at https://source.codeaurora.org/external/imx/uboot-imx.
The U-Boot for ConnectCore 6 Plus supports the following interfaces:
UART4 for console (115200/8/N/1)
10/100/1000Mbps Ethernet on Micrel KSZ9031 PHY (RGMII)
One-Time-Programmable (OTP) bits
Carrier board version and ID
Digi uses non-volatile media to store the carrier board version and ID. See Carrier board version and ID.