boards: Support Teensy Micromod

[KurtE]

The Sparkfun Teensy Micromod was designed by Paul of PJRC and manufactured and sold by Sparkfun.com

Note: Earlier I created an Issue about this, which was then converted to a discussion
#88210

The functionality of this board is very similar to the Teensy 4. It has the same basic pin definitions of the Teensy 4 but added 6 additional IO pins. Which added a lot of possibilities to use the flexio system in new ways, such as for camera input.

It was unclear if the board should be added here or all of this duplicated under Sparkfun, but now Sparkfun is also now responsible for the manufacturing and sales of the Teensy 4 and Teensy 4.1, here feels like a good place.

Note: I am mainly doing this as a learning experience on how to use zephyr directly, as most of my experiences with Zephyr is done through the current WIP Arduino Wrappers for some of their boards.

So far I duplicated the Teensy 4.1 files, then modified, like removed the ethernet and added the I2C2 object. I updated the flash information as these come with a 128mbit version versus the 64 on T4.1 or 16 on T4.

So far I have only test blink.

[nordicjm]

lowercase filename

[nordicjm]

Suggested change

	identifier: teensyMM
	identifier: teensymm

and filename to lowercase

[KurtE]

I renamed the files as I mentioned for earlier review plus the teensyMM -> teensymm

[nordicjm]

CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC=600000000 should come from DTS

[KurtE]

I have not done this one yet as this is a direct copy of the Teensy 41 defconf file
So have been trying to be consistent.

There are parts of the current configs that I don't fully understand why. Example, it shows support for the SDCard (SDIO) for the Teensy 4.1, but not the Teensy 4, yet the T4 can support it through the connector on the bottom
of the board.

Will look at this more

[josuah]

It seems like the Sparkfun Teensy Micromod is having a completely different pinout than the PRJC classic Teensy boards:

https://cdn.sparkfun.com/assets/5/a/3/6/0/MicroMod-Teensy_V1_3.pdf
https://learn.sparkfun.com/tutorials/designing-with-micromod/all#pin-specifications

Could you confirm which pinout you are documenting here?

As an alternative from the "teensy", you can also aim for the "boards/sparkfun/micromod" board as a directory as it is a SparkFun-made board.

Thank you for extending the MicroMod collection!

[KurtE]

It seems like the Sparkfun Teensy Micromod is having a completely different pinout than the PRJC classic Teensy boards:

I guess it depends on what we mean by pinout.
The pinout I am showing is the Teensy Arduino programming model for these boards.

That is, if you buy one of these boards, you are directed to install the Teensy boards through the Arduino
board manager (assuming Arduino 2.x) for 1.x you install using Teensyduino.

The pin numbers shown are the ones defined in cores/teensy4. They match the pins for the T4 with 6 pins added at the
end.

We could additionally show the Micromod pin numbers as well if desired. Like I could show the complete list for
the MMOD and add column with the MMOD pin number. I have all of that stuff in my Excel documents I created
when helping to add support for it when it was in alpha/beta mode.

As an alternative from the "teensy", you can also aim for the "boards/sparkfun/micromod" board as a directory as it is a SparkFun-made board.

That is a possibility. Although it gets confusing these days.

As I mentioned: From a recent blog on PJRC

SparkFun To Manufacture Teensy
We are excited to announce the expansion of our partnership with SparkFun Electronics to include the manufacturing of all Teensy products. Teensy 4.0, Teensy 4.1 and related accessories will now be manufactured by SparkFun in Colorado, USA.

SparkFun will also fulfill direct sales and also sell to other distributors, so you can continue to buy from stores which currently carry Teensy.

With Pin numbering/naming wondering if maybe from a current conversation on the Arduino Zephyr porting. Where one
suggestion was to explot the Zephyr GPIO nexus nodes abstraction. Don't know enough about that yet.
Right now playing along with some Arduino people on how to handle the pin numbering/naming on the Portenta H7 port/wrapping for zephyr.

[KurtE]

Note: I pushed up a new copy of the index.rst, which duplicates the MMOD pin mappings and it includes
the actual MicroMod pin numbers as well. Let me know what you think

[josuah]

Just to summarize the different pin naming used.

Teensy doc (PCB pin number)

SparkFun doc (using Arduino IDE names, PCB pin numbers of the original Teensy, and micromod pin number)

NXP doc (final chip numbers)

Here, this is turned into a teensy board: the pinout matches names of another PCB, given by SparkFun for backward compatibility purpose. It can become tedious to make the teensy pin numbers the standard while the pinout of the board is the MicroMod standard. Willing to try turning this into a MicroMod? :) This might really not be as hard as it sounds.

Links that helped me:

• https://github.com/zephyrproject-rtos/zephyr/pull/72985/files
• https://learn.sparkfun.com/tutorials/micromod-teensy-processor-hookup-guide/all
• https://www.nxp.com/products/i.MX-RT1060?tab=Documentation_Tab&linkline=Reference-Manual
• https://github.com/zephyrproject-rtos/hal_nxp/blob/master/dts/nxp/nxp_imx/rt/mimxrt1061dvj6a-pinctrl.dtsi

[josuah]

Every vendor has a different way to specify GPIO pins, sometimes it is <0 3 &gpioa 21>, sometimes it is <&gpio0 25>... A "mapping" or "nexus" helps vendor-neutralizing this all.

zephyr/boards/sparkfun/micromod/micromod_nrf52840.dts

Lines 38 to 61 in 3c2d2a6

	micromod_header: connector {
	compatible = "sparkfun,micromod-gpio";
	#gpio-cells = <2>;
	gpio-map-mask = <0xffffffff 0xffffffc0>;
	gpio-map-pass-thru = <0 0x3f>;
	gpio-map = <0 0 &gpio0 4 0>, /* A0 */
	<1 0 &gpio0 5 0>, /* A1 */
	<2 0 &gpio0 27 0>, /* D0 */
	<3 0 &gpio1 8 0>, /* D1/CAM_TRIG */
	<4 0 &gpio0 15 0>, /* I2C_INT# */
	<5 0 &gpio0 29 0>, /* G0/BUS0 */
	<6 0 &gpio0 3 0>, /* G1/BUS1 */
	<7 0 &gpio1 13 0>, /* G2/BUS2 */
	<8 0 &gpio1 12 0>, /* G3/BUS3 */
	<9 0 &gpio1 11 0>, /* G4/BUS4 */
	<10 0 &gpio0 17 0>, /* G5/BUS5 */
	<11 0 &gpio1 6 0>, /* G6/BUS6 */
	<12 0 &gpio1 4 0>, /* G7/BUS7 */
	<13 0 &gpio1 14 0>, /* G8 */
	<14 0 &gpio0 9 0>, /* G9/ADC_D-/CAM_HSYNC */
	<15 0 &gpio0 10 0>, /* G10/ADC_D+/CAM_VSYNC */
	//<16 NO CONNECTED /* G11/SWO */
	<17 0 &gpio0 20 0>; /* SPI_CS */
	};

Once this is done, it becomes possible to use new names like <&micromod_header 7 0>: micromod pin numbers... and that's it, we are done! You can then use it with --shield sparkfun_carrier_asset_tracker and all other carrier boards defined in the future.

Further reading:

• https://docs.zephyrproject.org/latest/hardware/porting/shields.html#gpio-nexus-nodes
• https://github.com/zephyrproject-rtos/zephyr/pull/72985/files
• https://github.com/devicetree-org/devicetree-specification/blob/4b1dac80eaca45b4babf5299452a951008a5d864/source/devicetree-basics.rst#nexus-nodes-and-specifier-mapping

[josuah]

The GPIO nexus probably does not need to be added on this PR though...

In addition to what @nordicjm pointed at (thank you!) I only spotted one small detail that needs at least a comment on the README.rst, or be removed to avoid dealing with it on this PR.

Besides this, LGTM thank you!

[kartben]

just pushed some minor doc fixups (including using transparent image and not the weird screenshot that was there initially)

also dropped the unrelated change you had made to blinky :)

[nordicjm]

compliance errors need resolving also

[nordicjm]

newline

[KurtE]

Sorry not sure what you mean by newline? do you mean I should add a blank line or
was there a windows cr/lf...

[nordicjm]

add a newline so that there is a newline e.g.:

	reg = <0x402a8000 0x4000>, <0x60000000 DT_SIZE_M(8)>;

	/* WINBOND flash memory*/
	w25q128jvxgim: w25q128jvxgim@0 {

[KurtE]

Just pushed up the change

[KurtE]

Oops pushed again. I see editor insterted tabs to align it... removed

[nordicjm]

this isn't right, nxp doesn't create teensy?

[KurtE]

I changed that to sparkfun as they are the one who sells it.
Note: I did not update the Teensy 4 or 4.1 versions which also have nxp.

[KurtE]

@nordicjm @josuah - Not sure what the twister builds are doing?

Is there something I need to change/do to make these work?

Thanks for all of your help

[josuah]

@KurtE It seems like the job that failed is unrelated to the board you added.
In such case, rebasing your branch on top of latest main might be enough to fix it.

Thank you for the efforts!

[KurtE]

In such case, rebasing your branch on top of latest main might be enough to fix it.
Thanks, did the trick

[josuah]

Closing-reopening to retrigger CI

[KurtE]

@josuah @nordicjm - looks like some twister issues. Where if I am reading this correct, the SD test is failing:

west build -p -b teensymm/mimxrt1062 samples/subsys/fs/fs_sample -T sample.filesystem.fat_fs

Again, sorry I am still getting my feet wet with this system!

That test does build for teensy41 and also fails on teensy40.

My wild guess is that maybe the failure is due to me having stuff in it .yaml file:

identifier: teensymm
name: PJRC TEENSY_MICROMOD
type: mcu
arch: arm
toolchain:
  - zephyr
  - gnuarmemb
  - xtools
ram: 768
flash: 8192
supported:
  - counter
  - gpio
  - sdhc
  - usb_device
  - netif:eth
testing:
  ignore_tags:
    - net
    - posix
vendor: sparkfun

I believe I should remove the netif:eth as that is not in the teensy40.yaml file, which makes sense as only the
T41 has the added support for Ethernet.

But: I still wondering about - sdhc
line, as it is not in T40 either, but is on T41. The main difference is that T4.1 has the SD adapter soldered
onto the Board itself, the Teensy 40 has pads on the bottom of the board:

On the Micromod, the pins are on the main main micromod connector: like everything else, gpio, usb, ...

Suggestions: I am thinking I might try removing those two defines? Or should I try adding it
to the ignore_tags ?

Note: I have tried the SD out on a couple of different MMod adapter boards. I believe I showed a few of them.
Here are three of them I use for most things with Teensy MMOD:

EDIT: picture was pasted upside down so editing top to bottom...
Bottom one is again ATP board with my own adapter to make things easier. Like test of my ILI9341 code running on
zephyr. Middle one is one I had a few partially assembled (all of the small pad components). and the top one
is the original one Paul of PJRC made while the Teensy MMOD was in beta. Note: Currently I can not use this one for
Zephyr as it is a locked Teensy, which can not be programmed using teensy_loader_cli.

Thanks again for all of your help

[josuah]

I would propose testing with the twister command: the build flags are very slightly different.

west twister -p teensymm/mimxrt1062 -s sample.filesystem.fat_fs --no-detailed-test-id

try removing those two defines? Or should I try adding it to the ignore_tags?

Maybe it would work to introduce everything except the SD card support, to allow merging this and work on troubleshooting it later if that makes things easier.

[KurtE]

Thanks, I tried that version of command line and it did not appear to work for MM nor 41...

I will try the changes that I mentioned and see if that helps.
Note: with my SD Test sketch it is still able to build and run and list the contents of the SD Card in my ATP adapter