Getting Started with the DK/BL/DL i.MX8MM

This guide is intended for first time users of the i.MX8MM Demo Kits and provides help in getting the board up and running. Each demo kit includes an i.MX8MM board and accessories like a power supply and a USB-to-Serial converter.

Hardware User Guide

Please consult the "Hardware User Guide" for detailed descriptions of the connectors and pinouts. You can find in in the products section of our website.

Full Guide for Dunfell BSP

For a full "Getting Started" guide including working with the Yocto Dunfell BSP, please see this page.

Connecting Power

Connect the power supply that came with the Demo Kit and plug it into the X1 socket on the board. Do not connect the power supply adapter to the mains yet. The power socket on the board is next to the two USB ports and has only two pins.

The following image shows the power connection done with an actual BL i.MX8MM board.

Connecting the Debug Cable

Now take the USB cable from the box and plug the USB-Mini plug into the USB-Mini port, named X3, at the side of the board next to the HDMI port. This connector is not really a USB port, but rather a serial port which allows the user access to UART 3 (Debug Console) and to communicate with the operating system later on without the need for a network setup. The other end of the cable (USB type A) has to be plugged into the USB-to-Serial adapter which came with the Demo Kit. The other end of the USB-to-Serial adapter can now be plugged into a computer.

The following image shows the BL i.MX8MM board with the debug cable attached as well as the power cable hooked up.

First Start

Before turning on the power for the BL i.MX8MM, make sure the USB-to-Serial adapter is plugged into the computer and that you have a terminal or console program running on the COM port the USB-to-Serial adapter is registered at. In Linux this will usually be a ttyUSB and in Windows a COM port device.

Once this is set up, the board can be powered on and text should appear in the terminal program, which means the operating system is starting. After a short wait the text output should stop and a login prompt is visible. The image below shows an example what should be shown in the terminal program. The login prompt is right at the end of the screen.

To log in use the user root and no password is needed. Once logged in there are many things that can be done with the system, but for a start why not try to turn the digital output 1 (DIO1) on and off. The pre-installed system should have the libgpiod library and its service programs already installed, this means we can use a program called gpioset to change the state of DIO1.

Configure DIO1 as an output and setting it to 1 (On).

gpioset gpiochip0 3=1

The onboard LED for DIO1 should light up and signal that its output is now active. With this one command the DIO1's corresponding GPIO was configured as an output and then set to 1 in one go.

Turning DIO1 off can be done by simply setting it to 0 with the following command:

gpioset gpiochip0 3=0

The LED for DIO1 should now be off again, meaning the output is no longer active.

This concludes the getting started guide for the BL i.MX8MM board. As mentioned above, also see other sections of this online documentation to learn more about other connection and communication options and how to setup your own Yocto Linux build system to create your own OS.

Troubleshooting

The BL i.MX8MM board in the Demo Kit should have an OS pre-installed on the internal eMMC memory and is ready to go. If this is not the case, you can still get the board working by making an SD card with a pre-build image from our server.

Download this "image" for example to get a base system. Unpack the file and write the .wic file onto a blank SD card. If you are working under Windows, you might have to rename the file extension from .wic to *.img to be able to use one of the many SD card writing programs available. Insert the SD card into the BL i.MX8MM boards SD card slot and plug in the power supply. The board should now boot from the SD card automatically and the above mentioned text should appear in the terminal program. You should now be able to log in and try the GPIO example above.