NXP i.MX 8M Plus on the Debix Model A SBC
NXP i.MX 8M Plus
NXP's i.MX 8 M Plus has some fairly powerful capabilities and an upstream device tree. 🙂
Source repositories for the i.MX series of processors are often under Freescale¨ not NXP because they were named before the merger of Freescale and NXP.
i.MX 8M Plus Evaluation Boards
NXP provide two official evaluation boards for the i.MX 8M Plus
[Evaluation Kit for the i.MX 8M Plus Applications Processor https://www.nxp.com/design/design-center/development-boards-and-designs/8MPLUSLPD4-EVK]
[i.MX 8M Plus Evaluation Kit Enabling Power Measurement https://www.nxp.com/design/design-center/development-boards-and-designs/8MPLUSLPD4-PEVK]
With upstream device tree.
Polyhex Debix Model A SBC
Polyhex have designed a range of inexpensive Debix Model A SBCs (Single Board Computers) based on the NXP i.MX 8M Plus. Prices vary depending on the amount or RAM (Random Access Memory) on the board and whether eMMC (embedded Multi Media Card) non-volatile storage is included on the the board.
For embedded Linux a Debix Model A with the minimum 2GB of RAM and no eMMC storage is fine (the Linux image and data can be stored on an SD card instead of on eMMC).
The upstream device tree for the Debix Model A is here
The Debix Model A SBC can connect direct to Debix 200A, 500A or 1300A camera modules via their 24Pin/0.5mm Pitch FPC cable.
Both the Raspberry Pi Camera modules and the Debix Model A use the modern industry-standard MIPI-CSI2 (Mobile Industry Processor Interface Camera Serial Interface 2) camera interface (the interface used by almost all modern smartphone cameras and almost all modern cameras for semi-autonomous vehicles).
However... they have a different number of pins - Debix use a 24Pin/0.5mm Pitch FPC connector, RPi cameras use a 15-way 1mm-pitch connector and the RPi 5 uses a 22-pin 0.5 mm pitch connector 🙈. A DEBIX IO Board (product number EMB-AS-E01) converts from the connectors on the Debix Model A to connectors the Raspberry Pi V2 and V3 Camera modules. The DEBIX IO Board also provides a PRi compatible GPIO header.
Polyhex Debix SoM A
The SoM (System on Module) A provides the NXP i.MX 8M Plus on a small circuit board. This is intended for production use and for prototyping it may be best to use it with the Debix SOM A I/O Board (often referred to in source code repositories by its product number BMB-08).
The upstream device tree for the Debix SoM A is here
The upstream device tree for the Debix SoM A mounted on the Debix SoM A I/O= board is here
The Debix SOM A I/O Board uses yet another camera connector - a dual in line 20pin/1.25mm Pitch connector see details in the Camera Adapter Board for DEBIX SOM A I/O Board User Guide - to connect it to a Debix camera requires a DEBIX Camera Adapter Board (product number EMB-AS-08).
By now you're probably getting a bit confused by some of the naming:
the "Debix Model A" and the "Debix S0M A" are not the same board 😉
the "DEBIX I/O Board" and the " Debix SOM A I/O Board" are not the same board 😉
bytesatwork i.MX 8M Plus SoM
bytesatwork in Winterthur also produce a [i.MX 8M Plus SoM https://www.bytesatwork.io/en/product/byteengine-imx8m-plus-quad/]
Roll Your Own Linux
All sounding too good to be true...?
The catch is that to attach peripherals like MIPI CSI-2 cameras to these platforms the correct kernel drivers have to be added to the device tree to form a custom Linux distribution for your application... that's difficult and will be the subject of the next section...