Boot the system | ConnectCore 6

This topic explains how to boot Digi Embedded Yocto images without updating the firmware on the internal eMMC. This is helpful during the development phase, as it preserves the original firmware on the SOM.

Open a serial connection

You must open a serial connection to communicate with your device.

Open a serial connection using any terminal program such as Tera Term, Minicom, Coolterm, or HyperTerminal. This documentation demonstrates using Minicom to work with the device command line.

Use the following settings:

Parameter Value

Port

Serial port where the device is connected

Baud rate

115200

Data bits

8

Parity

None

Stop bits

1

Flow control

None

Parameter	Value
Port	Serial port where the device is connected
Baud rate	115200
Data bits	8
Parity	None
Stop bits	1
Flow control	None

Reset the device by pressing the reset button on the board. Then immediately press any key in the serial terminal to stop the auto-boot process. The U-Boot bootloader prompt displays:

U-Boot dub-2017.03-r15.1 (Sep 20 2023 - 13:29:45 +0200)

CPU:   Freescale i.MX6Q rev1.6 at 792MHz
CPU:   Industrial temperature grade (-40C to 105C) at 38C
Reset cause: POR
I2C:   ready
DRAM:  1 GiB
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
In:    serial
Out:   serial
Err:   serial
Model: Digi International ConnectCore 6 Single Board Computer.
ConnectCore 6 SOM variant 0x02: Consumer quad-core 1.2GHz, 4GB eMMC, 1GB DDR3, -20/+70C, Wireless, Bluetooth, Kinetis
Board: ConnectCore 6 SBC, version 3, ID 129
Boot device: MMC4
PMIC:  DA9063, Device: 0x61, Variant: 0x60, Customer: 0x00, Config: 0x56
flash target is MMC:0
Net:   FEC [PRIME]
Fastboot: Normal
Hit any key to stop autoboot:  0
=>

Boot the system from network

This shows how to transfer the images to the target via TFTP or NFS, and mount an NFS root file system.

This requires that you set up your PC workstation as explained in Set up native Linux PC.

1. Prepare the device artifacts

Get the Digi Embedded Yocto firmware images to boot from network:
- The kernel file: zImage.
- The device tree: ccimx6sbc.dtb.
- The compressed root file system: <rootfs-file>.tar.xz.
1. After building the Digi Embedded Yocto firmware, you can find the image files inside the project directory at <project_folder>/tmp/deploy/images/ccimx6sbc.
2. You can download Digi-provided pre-built images from XWayland images.
Untar the root file system tarball (*.tar.xz) in the NFS exported directory of your development workstation. See Set up native Linux PC.
```
$ sudo tar xvfp image.tar.xz -C /exports/nfsroot-ccimx6sbc
```
Copy the kernel *.bin file to the TFTP exported directory of your development workstation.
```
$ sudo cp <kernel-file>.bin /tftpboot
```

Copy the device tree *.dtb file to the TFTP exported directory of your development workstation.

$ sudo cp <device-tree-file>.dtb /tftpboot

Read the board_id and soc_family of your platform from U-Boot to find out the appropriate device tree file for your platform. For example:

=> printenv board_id
board_id=129
=> printenv soc_family
soc_family=imx6q

The dtb file name of the device device tree for your platform follows the format: <soc_family>-<platform>-id<board_id>--6.6-r<X.Y>-<platform>-<date>.dtb

2. Configure your device’s network settings

Get a dynamic IP for your target:

=> setenv autoload no
=> dhcp

or you can set a static IP:

=> setenv ipaddr 192.168.115.222

Configure the IP of the development workstation with TFTP and NFS servers installed. See Set up native Linux PC:
```
=> setenv serverip 192.168.115.1
```

3. Boot from network

Boot from TFTP+NFS

Set the directory with the rootfs to mount. This directory is the one exported via NFS in your development workstation. See Set up an NFS server.
```
=> setenv rootpath /exports/nfsroot-ccimx6sbc
```
Specify the device tree (*.dtb) file name. This is the name of the *.dtb file you copied to the TFTP exported directory of your development workstation.
```
=> setenv fdt_file <device-tree-file>.dtb
```
Establish the kernel file (*.bin) name. This is the name of the *.bin file you copied to the TFTP exported directory of your development workstation.
```
=> setenv zimage <kernel-file>.bin
```
Save the changes.
```
=> saveenv
```
Boot from TFTP.
```
=> dboot linux tftp
```
You can make these changes persistent by writing the following command:

=> setenv bootcmd 'dboot linux tftp' => saveenv

The target now loads the kernel and device tree from the TFTP server and the root file system from the NFS server.

Boot entirely from NFS

To avoid using TFTP for kernel and device tree files and boot everything from NFS, copy the kernel *.bin and device tree *.dtb files to the NFS-exported directory of your development workstation (instead of to the TFTP directory). See Set up an NFS server.

=> dboot linux nfs

Boot from microSD card

U-Boot can start a complete Digi Embedded Yocto system from a microSD card. See Boot from microSD card for instructions on creating a bootable microSD card and booting from it.