verypossible / nerves_system_cl_iot_gate_imx8plus

Nerves System - CompuLab IoT Gateway iMX 8m Plus

Nerves CompuLab IOT-GATE-IMX8PLUS

This is the base Nerves System configuration for the CompuLab IOT-GATE-IMX8PLUS.

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Feature	Description
CPU	4 x 1.8 GHz ARM Cortex-A53
MCU	800 Mhz ARM Cortex-M7
Memory	1-8 GB DRAM
Storage	16-128 GB eMMC Flash
Linux kernel	5.15 imx-linux
IEx terminal	UART ttymxc1
GPIO, I2C, SPI	Yes - Elixir Circuits
Camera	None
Ethernet	2x 1000Mbps
WiFi	802.11ax WiFi
HW Watchdog	Hardware watchdog enabled on boot. Be sure to enable heart in your vm.args or the device will reboot

Using

The most common way of using this Nerves System is create a project with mix nerves.new and to export MIX_TARGET=cl_iot_gate_imx8plus. See the Getting started guide for more information.

If you need custom modifications to this system for your device, clone this repository and update as described in Making custom systems.

Preparing your CompuLab IOT-GATE-IMX8PLUS

The IOT-GATE-IMX8PLUS gateway uses the hardware BOOT part 1 to store the U-Boot bootloader. The system needs to be initially programmed using the uuu programming utility.

To program the system you will need the bootloader file from the NERVES_SYSTEM images directory, and a disk image from the FWUP file.

For mor information see the initialize_firmware project in the system directory.

Provisioning devices

This system supports storing provisioning information in a small key-value store outside of any filesystem. Provisioning is an optional step and reasonable defaults are provided if this is missing.

Provisioning information can be queried using the Nerves.Runtime KV store's Nerves.Runtime.KV.get/1 function.

Keys used by this system are:

Key	Example Value	Description
nerves_serial_number	"12345678"	By default, this string is used to create unique hostnames and Erlang node names. If unset, it defaults to part of the BBB's serial number.

The normal procedure would be to set these keys once in manufacturing or before deployment and then leave them alone.

For example, to provision a serial number on a running device, run the following and reboot:

iex> cmd("fw_setenv nerves_serial_number 12345678")

This system supports setting the serial number offline. To do this, set the NERVES_SERIAL_NUMBER environment variable when burning the firmware. If you're programming MicroSD cards using fwup, the commandline is:

sudo NERVES_SERIAL_NUMBER=12345678 fwup path_to_firmware.fw

Serial numbers are stored on the MicroSD card so if the MicroSD card is replaced, the serial number will need to be reprogrammed. The numbers are stored in a U-boot environment block. This is a special region that is separate from the application partition so reformatting the application partition will not lose the serial number or any other data stored in this block.

Additional key value pairs can be provisioned by overriding the default provisioning.conf file location by setting the environment variable NERVES_PROVISIONING=/path/to/provisioning.conf. The default provisioning.conf will set the nerves_serial_number, if you override the location to this file, you will be responsible for setting this yourself.