Teensy MicroMod

[vjmuzik]

I couldn’t help but notice the latest core updates on GitHub and I’m curious about this update here. I can only assume there’s going to be a Teensy 4.x with the Sparkfun MicroMod form factor, more specifically a different form factor for embedded projects. Is there any news on this that can be shared at this time besides what’s already viewable in the update?

[PaulStoffregen]

Is there any news on this that can be shared at this time besides what’s already viewable in the update?

Officially, no news yet.

Unofficially, good guesswork.

[luni]

Wow, that is really great news. Do you plan to stick to the Adafruit pinout? Any rough idea when this will be ready? I need to do a board in a couple of weeks, would love to use/test this form factor.

[brtaylor]

Wow, great news! Especially if it has an industrial temperature range, or close to it, would be nice to use in commercial products.

[WMXZ]

would be interesting to see if flexibility of T4.1 (multiple I2S data ports, PSRAM could be mapped to Sparkfun form factor)
I guess, I stick with T4.1 for some time.

EDIT: OK I may change my mind if there is a camera connection (Sparkfun ML board)

[skpang]

Wow, interesting..

The MicroMod M.2 connector has 75 pins. That means more IO pins from the Teensy can be brought out.

[blackketter]

Wow, interesting..

The MicroMod M.2 connector has 75 pins. That means more IO pins from the Teensy can be brought out.

Definitely interesting!

Looking here https://www.sparkfun.com/micromod#tech-specs at least 8 of those 75 pins are reserved for mechanical keying.

And assuming that a MicroMod Teensy would be compatible with the other MicroMod carrier boards, many of the pins are already specified by that standard. Of course, if you want to design a carrier board specific to the Teensy MicroMod processor board, I'd expect you to be able to repurpose some of the pins (knowing which Teensy pin they correspond to.)

[defragster]

SFUN MicroMod connector page says 67 pins.

5x M.2 MicroMod Connectors
Key: E
Height: 4.2mm
Pin count: 67
Pitch: 0.5mm

Given Paul can't comment ... reading the tea leaves is fun ...

... first assumed the _mm.ld was a placeholder for the HAB work builds ... then saw this thread

beta .ld suggests no PSRAM/EXTMEM - but a 16MB Flash - a WIP ... pin info split between 4.0 and 4.1

... Others available show room for bottom SMD's ...

Supported Interfaces:

USB for programming and serial debug
2x Analog Dedicated
2x PWM Dedicated
2x Digital I/O Dedicated
12x GPIO
2x I2C
2x SPI
2x UART
SDIO
USB-HOST
CAN
SWD
PDM / PCM / I2S
Differential ADC

[PhilB]

Interesting to say the least. I wonder how ethernet would be handled. Hypothetically, of course.

[KurtE]

Looking at the GPIO pins defined in core_pins.h
I believe pins: 0-33 match T4.1, 34-39 SDIO
and pins 40-45 look like something different
Pin Port-Pin
34 3-15 SDIO? Note I converted GPIO6 back to 1... 7 to 2 8 to 3...
35 3-14
36 3-13
37 3-12
38 3-17
39 3-16

40 2-04
41 2-05
42 2-06
43 2-07
44 2-08
45 2-09
I don't see GPIO2-4 to GPI2-9 on T4 or T4.1...

EDIT: 34 is fine, my excel was off...

[skpang]

Looks like everybody is using the M.2 connector.

[KurtE]

Again if I am looking at the pin data correctly
40 2-04 are pins B0_04
41 2-05 B0_05
42 2-06 B0_06
43 2-07B0_07
44 2-08B0_09
45 2-09 B0_09

So that would probably imply we would have pins GPIO2 pins 0-12, 16-19, 28-29 So pretty nice port IO for this one.

[PhilB]

I have only a surface understanding of the core code so I could be wrong but looking at the github page, it appears the hypothetical micromod board would have fewer analog and digital I/O pins than the T4.1. Is that right? I assume that the 55 digital for the T4.1 include memory and SD card pins.

#if defined(ARDUINO_TEENSY40)
  #define NUM_DIGITAL_PINS  40
  #define NUM_ANALOG_INPUTS 14
#elif defined(ARDUINO_TEENSY41)
  #define NUM_DIGITAL_PINS  55
  #define NUM_ANALOG_INPUTS 18
#elif defined(ARDUINO_TEENSY_MICROMOD)
  #define NUM_DIGITAL_PINS  46
  #define NUM_ANALOG_INPUTS 14
#endif

Looking forward to seeing a pinout definition for MM board.

[KurtE]

That would be my guess, but again this is a beta build for a non-announced maybe will be released product which may or may not be final....

The only other thing we know is looking at what the MicroMod connector looks like, example extract from their Carrier board schematic:


As for which of the Teensy pins connect to each of these pins, I could guess on a reasonable number of them, but best thing to do is wait and see.

Obviously there are many details that we can only guess at. For example does it have external PSRAM? So far does not look like it as the startup code does not call the code to initialize it, BUT: also could be that just has not been updated yet. But it also looks like the flash will be twice as big, but again that is all of these details could change.

[PhilB]

Yes, wait and see is good advice. Though, having a product based on the T4.1, I am keenly interested in this development. I think I see the potential for a pony in there.

[skpang]

There is a spreadsheet of the pinout but Teensy is not on there:

https://docs.google.com/spreadsheets...J8k/edit#gid=0

[PaulStoffregen]

Obviously there are many details that we can only guess at. For example does it have external PSRAM? So far does not look like it as the startup code does not call the code to initialize it, BUT: also could be that just has not been updated yet. But it also looks like the flash will be twice as big, but again that is all of these details could change.

Unofficially of course, the code is pretty unlikely to change.

[manitou]

I've briefly played with the sparkfun M4/SAMD51 micromod processor board and the ATP carrier board. The M4 board has the SPI flash on the underside. I assume the Teensy 4 micromod board will have the 16 MB SPI flash on the underside, and along with the 1062 chip there will be the MKL boot chip, crystals (24MHz and 32KHz), pin 13 LED. Will there be room for Ethernet PHY chip and ribbon-cable connector on the processor board??

The carrier board brings out JTAG, so JTAG enthusiasts may have access to T4 JTAG ? The ATP carrier also has USB host connection along with JST/LiPo and many data pins.

The microSD on the data logging carrier board can be controlled by SDIO me thinks... or maybe just SPI ?

T4 micromod should be interesting.

[blackketter]

I sincerely hope that the MicroMod pin labelled RESET# is a real old-fashioned cpu reset pin as described in the MicroMod pin description.

[PhilB]

I wonder if, instead of the 6 pin header, all the ethernet pins (R+, R-, T+, T- and LED) go through the micromod pins. They push USB D+ and D- through them so differential pairs are possible.

[blackketter]

I wonder if, instead of the 6 pin header, all the ethernet pins (R+, R-, T+, T- and LED) go through the micromod pins. They push USB D+ and D- through them so differential pairs are possible.

If they did then it probably wouldn't be MicroMod compatible. The MicroMod pinout here https://www.sparkfun.com/micromod#tech-specs doesn't have any provision for ethernet pins.

[PhilB]

Well, I'm not sure how strict that is. The SFE docs say you don't have to adhere to the pinouts. Honestly, the same 2x3 ethernet header on the compute board would decrease my interest level. At least with the T4.1, I can bring that through to the base board and make for a secure connection. In my product's intended environment, pin headers are not appreciated.

[defragster]

The new beta _MM.ld doesn't show space for QSPI PSRAM - maybe no room on board for that pinout? Would be proper awesome though.

Would be nice if the PHY chip and 6 pins fit on the TeensyMM card, but space is tight - magjack could reside on the base board.

Not sure RESET on 1062 can be done - or it would be on the current 4.x's. Expect that will be Teensy Program - otherwise it won't act like a Teensy?

[blackketter]

Well, I'm not sure how strict that is. The SFE docs say you don't have to adhere to the pinouts. Honestly, the same 2x3 ethernet header on the compute board would decrease my interest level. At least with the T4.1, I can bring that through to the base board and make for a secure connection. In my product's intended environment, pin headers are not appreciated.

Sorry, can you point me to the SFE docs? I'm not seeing them...

[blackketter]

The new beta _MM.ld doesn't show space for QSPI PSRAM - maybe no room on board for that pinout? Would be proper awesome though.

Would be nice if the PHY chip and 6 pins fit on the TeensyMM card, but space is tight - magjack could reside on the base board.

Not sure RESET on 1062 can be done - or it would be on the current 4.x's. Expect that will be Teensy Program - otherwise it won't act like a Teensy?

There are two relevant pins in the MicroMod specification:

RESET - Input to processor. Open drain with pullup on processor board. Pulling low resets processor.

and

BOOT - Input to processor. Open drain with pullup on processor board. Pulling low puts processor into special boot mode. Can be left NC.

My expectation was that BOOT would be used for the PROG pin that puts the teensy into programming mode.

I suppose that the RESET pin could be a Teensy 3.2-style reset pin or a Teensy 4.0 ON/OFF pin. To support a T3.2 style reset this would probably require some integration with the bootloader chip.