Support Teensy (PJRC and Sparkfun) Micromod

[KurtE]

Currently you have support for the Teensy(PJRC) 4 and 4.1, would be nice if you also supported
the Teensy Micromod (which was designed by PJRC and Manufactured by Sparkfun).

Note: Teensy 4 and 4.1 are now also manufactured by Sparkfun. For Arduino, support for this board is contained in the same board package as all of the other Teensy boards. The main difference with this board, is the
form factor (Micromod), which pins are exposed and the size of the flash memroy.

I thought I might hack it in, but I noticed that a few of the files like:
.../zephyr/boards/pjrc/teensy4/teensy4-pinctrl.dtsi:

have comments in them like:

* Note: File generated by gen_board_pinctrl.py
 * from teensy4.mex

So, wondering if these scripts and input files still exist somewhere?

I believe a version of the python script is up at:
https://github.com/zephyrproject-rtos/hal_nxp/blob/master/mcux/scripts/pinctrl/gen_board_pinctrl.py

But no idea about the .mex file. There may be other such generated files.

Thoughts?

[mariopaja]

Hi @KurtE

You can create .mex file using
https://www.nxp.com/design/design-center/software/development-software/mcuxpresso-software-and-tools-/mcuxpresso-config-tools-pins-clocks-and-peripherals:MCUXpresso-Config-Tools.

There you can do a full setup of the GPIOs, save the .mex file, and then with the script generate .dtsi file.

However, before doing all this you can start by creating the board definition with uart as the only node. This will help you test the board. Then you can go and generate the .mex and .dtsi files

[KurtE]

Thanks @mariopaja,

I think I was looking at this wrong. That was I thought the Teensy4.mex for was specifically for Teensy4, where it is probably
reasonably generic for the different Teensy 4.x boards. What I mean is, I don't think any of the zephyr stuff here refers to
the names that logical objects and pins for the Teensy 4.

So far, my main playing with zephyr is through helping flesh out and test the Arduino wrappers of some of their boards, so for
example there are tables of logical objects:
For example: Serials is defined in the overlay like:
serials = <&board_cdc_acm_uart>, <&usart1>, <&usart2>, <&uart4>, <&usart6>;
And Serial1 is defined as using usart1, ... Serial4 uses usart6...
Likewise for pin numbers:

	zephyr,user {
		digital-pin-gpios = <&arduino_header 6 0>,
						<&arduino_header 7 0>,
...
						<&arduino_header 18 0>,
						<&arduino_header 19 0>,
						<&gpiog 14 0>,				/* TX1 - 14 */
						<&gpioc 7 0>,
						<&gpioh 13 0>,

So on this board if I wish to work on logical pin 14, I would use the api with 14 and it does the look up...
Where here I believe I would use <&gpiog 14 0>

The Micromod has similar pin numbers as the T4 and 4.1 like:

<style> </style>

Pin	MM Pin	MM Func	Name
00	19	*	AD_B0_03
01	17	*	AD_B0_02
02	47	*	EMC_04
03	32	*	EMC_05
04	10	*	EMC_06
05	18	*	EMC_08
06	71	*	B0_10
07	56		B1_01
08	54		B1_00
09	69	*	B0_11
10	55	FNCS0	B0_00
11	59	*	B0_02
12	61	*	B0_01
13	57	*	B0_03

So I mainly need to add the documentation page of it.
Thanks again
Kurt