The ConnectCore 91 SOM does not have a corresponding development kit (DVK). This Get Started guides you on how to emulate a ConnectCore 91 using a ConnectCore 93 Development Kit instead.

The ConnectCore 93 Development Kit is shipped without a default operating system loaded. Only U-Boot is flashed in the device. This step demonstrates how to install Digi Embedded Yocto in your ConnectCore 93 Development Kit.

  1. Establish a serial connection with your device

  2. Download the firmware

  3. Program the firmware

1. Establish a serial connection with your device

Open a serial connection with the device. You can use any serial terminal program such as Tera Term, Minicom, CoolTerm, or HyperTerminal.

PuTTY terminal program is not recommended due to an incompatibility with the USB/serial driver.

Open a serial connection with 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

2. Download the firmware

To access firmware images, please fill out the following form to provide some information so we can better understand your project needs.

If the form doesn’t load after a few seconds, you may need to refresh the page. Contact Digi Support Services if you are not able to access the firmware images.

The ConnectCore 91 SOM does not have a corresponding development kit (DVK). This form downloads ConnectCore 93 firmware images that let you emulate a ConnectCore 91 using a ConnectCore 93 Development Kit.

If you have a ConnectCore 93 Development kit already set up, you can go directly to the instructions about how to emulate a ConnectCore 91.

3. Program the firmware

There are multiple methods of programming the firmware to the target:

Program the firmware using UUU

  1. Decompress the zip file in a directory of your choice.

  2. Download the latest Universal Update Utility (UUU), a software tool from NXP.

    UUU version should be v1.5.182 or higher.

  3. Place the uuu executable in a directory in your PATH, such as /usr/bin.

  4. Install udev rules to allow any user to run uuu to access the USB port:

    $ sudo sh -c "uuu -udev >> /etc/udev/rules.d/70-uuu.rules"
$ sudo udevadm control --reload

  5. Connect a USB type-C cable to your development PC and the other end to the target USB type-C connector.

  6. 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 SPL dub-2023.04-r3.2 (Jan 30 2024 - 10:57:23 +0000)
SOC: 0xa1009300
LC: 0x2040010
PMIC: Over Drive Voltage Mode
M33 prepare ok
Normal Boot
Trying to boot from BOOTROM
Boot Stage: Primary boot
image offset 0x0, pagesize 0x200, ivt offset 0x0
Load image from 0x4f400 by ROM_API
NOTICE:  BL31: v2.8(release):lf-6.1.55-2.2.0-0-g08e9d4eef226-dirty
NOTICE:  BL31: Built : 16:47:44, Jan 30 2024


U-Boot dub-2023.04-r3.2 (Jan 30 2024 - 10:57:23 +0000)

CPU:   i.MX93(52) rev1.1 1700 MHz (running at 1692 MHz)
CPU:   Industrial temperature grade (-40C to 105C) at 42C
Reset cause: POR (0x1)
DRAM:  992 MiB
Core:  202 devices, 29 uclasses, devicetree: separate
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
In:    serial
Out:   serial
Err:   serial
Model: Digi ConnectCore 93 Development Kit
ConnectCore 93 SOM variant 0x01: 992 MiB LPDDR4, Wi-Fi, Bluetooth
Boot:  MMC0

BuildInfo:
  - ELE firmware version 0.1.0-44880904

flash target is MMC:0
Net:   eth0: ethernet@428a0000 [PRIME]
Fastboot: Normal
Normal Boot
Hit any key to stop autoboot:  0
=>
    Information in the console log may vary.

  7. On the target, in U-Boot, execute the following command:

    => fastboot 1

  8. On your development PC, change to the directory where you extracted the ZIP file:

    $ cd <zip-folder>

  9. Run the install_linux_fw_uuu.sh script with -h parameter to check the syntax:

    $ ./install_linux_fw_uuu.sh -h
############################################################
#           Linux firmware install through USB OTG         #
############################################################
Usage: ./install_linux_fw_uuu.sh [options]

  Options:
   -b                     Activate bootcount mechanism (3 boot attempts).
   -d                     Install firmware on dualboot partitions (system A and system B).
                          (Implies -b).
   -h                     Show this help.
   -i <dey-image-name>    Image name that prefixes the image filenames, such as 'dey-image-qt',
                          'dey-image-webkit', 'core-image-base'...
                          Defaults to 'core-image-base' if not provided.
   -k <dek-filename>      Update includes dek file.
                          (implies -t)."
   -n                     No wait. Skips 10 seconds delay to stop script.
   -t                     Install TrustFence artifacts.
   -u <u-boot-filename>   U-Boot filename.
                          Auto-determined by variant if not provided.

  10. To program the default image files (core-image-base):

    $ ./install_linux_fw_uuu.sh

  11. Once the firmware is installed, the device boots automatically. The default username is root with no password.

Program the firmware using uSD card

  1. Decompress the zip file.

  2. Place the decompressed files in the root of a FAT-formatted microSD card and insert it in the microSD socket of the board.

  3. 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 SPL dub-2024.04-r1.1-git+g93da01eb81e+p0 (Aug 21 2024 - 16:13:01 +0000)
SOC: 0xa0009100
LC: 0x2040010
PMIC: PCA9451A
PMIC: Nominal Voltage Mode
DDR: 3733MTS
Normal Boot
Trying to boot from BOOTROM
Boot Stage: Primary boot
image offset 0x0, pagesize 0x200, ivt offset 0x0
Load image from 0x3d400 by ROM_API
NOTICE:  TRDC init done
NOTICE:  BL31: v2.10.0  (release):android-14.0.0_2.0.0-rc3-0-g9ce177d6d-dirty
NOTICE:  BL31: Built : 10:04:22, May 29 2024

U-Boot dub-2024.04-r1.1-git+g93da01eb81e+p0 (Aug 21 2024 - 16:13:01 +0000)
Reset Status: POR
CPU:   NXP i.MX91(31) Rev1.0 A55 at 1400 MHz
CPU:   Industrial temperature grade  (-40C to 105C) at 31C
DRAM:  480 MiB
Core:  200 devices, 28 uclasses, devicetree: separate
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
In:    serial
Out:   serial
Err:   serial
Model: Digi ConnectCore 91 Development Kit
ConnectCore 91 SOM variant 0x01: 480 MiB LPDDR4, Wi-Fi, Bluetooth
  Board version undefined, ID undefined
Boot:  MMC0
BuildInfo:
  - ELE firmware version 1.1.0-17eafba6
flash target is MMC:0
Net:   eth0: ethernet@428a0000 [PRIME]
Fastboot: Normal
Normal Boot
Hit any key to stop autoboot:  0
=>
    Information in the console log may vary.

  4. To install the default firmware images (core-image-base) into the internal eMMC, run the following command:

    => run install_linux_fw_sd

    To program other images, set the variable image-name to the DEY image name (such as dey-image-webkit or core-image-base) before running the script.

    => setenv image-name core-image-base
=> run install_linux_fw_sd

  5. Once the firmware is installed, the device boots automatically. The default username is root with no password.

    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

Program the firmware using USB mass storage

Follow these steps to install Yocto in the device:

  1. Decompress the zip file.

  2. Place the decompressed files in the root of a FAT-formatted USB mass storage and insert it in the USB host connector of the board.

  3. 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 SPL dub-2024.04-r1.1-git+g93da01eb81e+p0 (Aug 21 2024 - 16:13:01 +0000)
SOC: 0xa0009100
LC: 0x2040010
PMIC: PCA9451A
PMIC: Nominal Voltage Mode
DDR: 3733MTS
Normal Boot
Trying to boot from BOOTROM
Boot Stage: Primary boot
image offset 0x0, pagesize 0x200, ivt offset 0x0
Load image from 0x3d400 by ROM_API
NOTICE:  TRDC init done
NOTICE:  BL31: v2.10.0  (release):android-14.0.0_2.0.0-rc3-0-g9ce177d6d-dirty
NOTICE:  BL31: Built : 10:04:22, May 29 2024

U-Boot dub-2024.04-r1.1-git+g93da01eb81e+p0 (Aug 21 2024 - 16:13:01 +0000)
Reset Status: POR
CPU:   NXP i.MX91(31) Rev1.0 A55 at 1400 MHz
CPU:   Industrial temperature grade  (-40C to 105C) at 31C
DRAM:  480 MiB
Core:  200 devices, 28 uclasses, devicetree: separate
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
In:    serial
Out:   serial
Err:   serial
Model: Digi ConnectCore 91 Development Kit
ConnectCore 91 SOM variant 0x01: 480 MiB LPDDR4, Wi-Fi, Bluetooth
  Board version undefined, ID undefined
Boot:  MMC0
BuildInfo:
  - ELE firmware version 1.1.0-17eafba6
flash target is MMC:0
Net:   eth0: ethernet@428a0000 [PRIME]
Fastboot: Normal
Normal Boot
Hit any key to stop autoboot:  0
=>
    Information in the console log may vary.

  4. To install the default firmware images (core-image-base) into the internal eMMC, run the following command:

    => run install_linux_fw_usb

    To program other images, set the variable image-name to the DEY image name (such as dey-image-webkit or core-image-base) before running the script.

    => setenv image-name core-image-base
=> run install_linux_fw_usb

  5. Once the firmware is installed, the device boots automatically. The default username is root with no password.

    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

4. Emulate a ConnectCore 91 SOM on a ConnectCore 93

The installed firmware images contain a boot script that allows you to emulate a ConnectCore 91 SOM on a ConnectCore 93 (Digi part number CC-WMX-F26D-L1). This boot script deactivates hardware that’s not available on the ConnectCore 91. More specifically, it:

  • Disables one of the two Cortex-A55 cores

  • Disables the Cortex-M33

  • Disables the NPU

  • Disables video

  • Disables camera

  • Limits RAM memory to 512 MiB

To enable the emulation:

  1. Boot your ConnectCore 93 and stop the boot process in the U-Boot console.

  2. Type the following command to enable the emulation:

    => setenv emulate-cc91 yes

  3. Optionally, save the environment if you always want to boot with emulation:

    => saveenv

  4. Boot the device:

    => boot

    The boot log will include a message stating Emulating a ConnectCore 91 (emulate-cc91=yes).