TS-4100 baseboard ID
All of our off the shelf baseboards contain a hard-wired 8-input multiplexer to indicate the baseboard model. This is not required to implement in custom baseboards, but it can be useful to identify the board model in software. The baseboard model is determined in the bootloader and the proper device tree is selected for the respective baseboard. For example, the TS-8551-4100 would use the "imx6ul-ts4100-16.dtb" device tree file. In U-Boot the device tree IDs are specified in hex, so 0x16 (U-Boot defaults to using base 16 for number representations) will match baseboard ID 22. If a board does not have a specific device tree, it will fall back to the default device tree which is "imx6ul-ts4100.dtb".
4 DIO pins are used to obtain the baseboard model ID. The red LED (CN2_06), green LED (CN2_08), BUS_DIR (CN1_98), and BD_ID_DATA (CN1_83) are used for this purpose. All of these IO pins can be used normally outside of acquiring the ID number.
The 6 least significant input pins (Y0 - Y5) are used to define the baseboard model. The upper two inputs (Y6 and Y7) define board revision.
For custom baseboards we have reserved the address 42 which will never be used by our standard products.
|1||Reserved, do not use|
|42||Reserved for customer use, never used by us|