Update firmware from microSD

If you don't have a TFTP server, you can still program Yocto in your ConnectCore 6UL device using a microSD card. The microSD card must be FAT formatted.

To program Yocto from the microSD card:

Place the Yocto firmware images in the root of the FAT formatted microSD card:
- <u-boot-file>.imx
- <boot-file>.boot.ubifs
- <recovery-file>.recovery.ubifs
- <rootfs-file>.ubifs
After building the Yocto firmware, you can find the image files inside the project directory at:
<project>/tmp/deploy/images/ccimx6ulsbc

Note You can download Digi provided pre-built image from:

U-Boot: Download the *.imx file for your hardware variant from ftp://ftp1.digi.com/support/digiembeddedyocto/2.2/r3/images/ccimx6ulsbc/x11/.

See hardware variants to verify which U-Boot binary you need.

Connect the board to your host computer. See Step 2: Set up the hardware for instructions.
Open a serial connection to the serial port the device is connected to. Use the following settings:
- Port: Serial port where the device is attached
- Baud rate: 115200
- Data Bits: 8
- Parity: None
- Stop Bits: 1
- Flow control: None

Reset the device (press the Reset button on the board) and immediately press a key in the serial terminal to stop the auto-boot process. You will be stopped at the U-Boot bootloader prompt:

U-Boot dub-2015.04-r8.3+g0de0373ade (Apr 24 2017 - 02:22:53)
CPU: Freescale i.MX6UL rev1.1 528 MHz (running at 396 MHz)
CPU: Industrial temperature grade (-40C to 105C) at 35C
Reset cause: POR
I2C: ready
DRAM: 256 MiB
MCA: HW_VER=1 FW_VER=0.6
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, Wireless, Bluetooth
Board: ConnectCore 6UL SBC, version 2, ID 135
Net: FEC0
Hit any key to stop autoboot: 0
=>

Optional. Update the U-Boot image:
1. Execute the following command to update the U-Boot image:
2. Reset the board to boot into the recently updated U-Boot, and press any key to stop the auto-boot process.
3. Reset the U-Boot environment to default values (this will not reset protected variables like the MAC address). To do so, issue this command:
```
=> env default -a
```
4. Save the U-Boot environment to apply the default configuration.
```
=> saveenv
```

Update the boot image (extension .boot.ubifs) by executing this command:
```
=> update linux mmc 0 fat <boot-file>.boot.ubifs
```

Wait until the process ends, then update the root file system image (extension .ubifs) by issuing this command:
```
=> update rootfs mmc 0 fat <rootfs-file>.ubifs
```
Wait until the process ends, then update the recovery image (extension .recovery.ubifs) by issuing this command:
```
=> update recovery mmc 0 fat <recovery-file>.recovery.ubifs
```

You can format the update partition or directly boot the new firmware:
- To format the update partition, run the following commands. They boots in recovery mode to format the partition and then boots the device normally with the new firmware:
```
=> setenv recovery_command wipe_update
=> saveenv
=> run recoverycmd
```
- If the update partition is already formatted or you want to preserve its contents, boot the device with the firmware you have just programmed:
```
=> boot
```