SparkFun Forums

[Furusato]

Hi, I'm considering purchase of the STM32 version of the Micromod and was wondering which of the carrier boards provided the maximum number of Analog Digital Converters (ADCs). I'm guessing the ATM carrier board would have the most of course, but if there's only two (A0 and A1from what I can see from the schematic) then any of the Micromod carrier boards would be roughly the same in this regard. Are there only two ADCs on an STM32?

Am I missing something? According to https://store.micropython.org/product/PYBv1.1#image5 the Pyboard seems to have 12 ADCs.

Thanks!

[TS-Russell]

There are only 2 dedicated pins, but each processor will have many more capabilities that can be controlled/set via programming

The STM32 should have 14 ADC-capable pins that could be assigned to the ATP pins....

I haven 't tried it before but looks like the user can potentially get 15x ADC pins on the MicroMod STM32. I was referencing the STM32 IC pinout [ https://microcontrollerslab.com/stm32f4 ... -examples/ ] with the schematic [ https://cdn.sparkfun.com/assets/8/a/a/7 ... cessor.pdf ] and it looks like you could use the other dedicated pins for ADC

[Furusato]

Thanks, it took me awhile even to quite follow what the page you referenced actually meant. On the Discovery board that would be GPIO7 to GPIO22, the lavender colored tags on that diagram. But translating that to the actual pins, first on the Micromod STM32, then the carrier boards, is not trivial. It's first translating the diagram from the STM Discovery board's pins to the STM schematic on the SparkFun STM32 schematic, then figuring out which pins those are on the Micromod, then figuring out which pins show up on the various carrier boards. And of course each board has its own (often multiple) ways of describing a pin. And then knowing if the pin is actually available or if it's being required for something else.

https://cdn.sparkfun.com/assets/8/a/a/7 ... cessor.pdf
https://cdn.sparkfun.com/assets/2/9/5/8 ... ematic.pdf
https://cdn.sparkfun.com/assets/5/8/e/f ... ematic.pdf
https://cdn.sparkfun.com/assets/c/e/3/f ... cromod.pdf

[TS-Russell]

True - On the other hand, if you simply wanted to extend ADC functionality, you could chain several of these https://learn.sparkfun.com/tutorials/qw ... okup-guide with muxes https://www.sparkfun.com/products/16784 ... 1622745974

Or alternatively, the teensy 4.1 has 18 analog pins that can be read via its single ADC https://www.sparkfun.com/products/16771 ... 1622745974 if incorporating pre-processed signal is an option

[Furusato]

Thanks, I'm specifically looking for an I2C slave implementation, and was told by someone in on the MicroPython team that the STM32 (like the PyBoard or ST NUCLUO boards) had implemented it, with the Sparkfun Micromod STM32 showing up as one of the options, whereas so far as I understand it's not implemented on the Teensy.

I took the PDF of the Micromod STM32 and mapped (in color) between the pins of the STM32 and the Micromod (in Inkscape). Now I've got to map to first the ATM carrier and then my goal, which would be either the Feather or the Data Logger, to see if I can get six ADCs (which is what I actually need).

Curiously, unless I'm doing it wrong I wasn't able to determine where STM32's C3, labeled as "FLASH_CS", ends up on the Micromod. It doesn't look like it goes anywhere...