Search found 142 matches

by chrismas9
Wed Apr 08, 2020 12:54 pm
Forum: Hardware Projects
Topic: Smallest MCU for micropython
Replies: 12
Views: 634

Re: Smallest MCU for micropython

It's more than a board directory. Some of the changes are in the port files. I will try to put something useful together. I just nuked my laptop and I haven't installed everything yet so I probably won't be able to do anything until next week. I am not using a filesystem. I debug in RAM using Thonny...
by chrismas9
Wed Apr 08, 2020 2:12 am
Forum: Hardware Projects
Topic: Smallest MCU for micropython
Replies: 12
Views: 634

Re: Smallest MCU for micropython

I am developing products using L072, primarily because of its on board EEPROM. I did an exercise first to build a minimum useful STM32 port and got it down to about 150k. Not all features can be disabled in mpconfigboard.h. You need to work through all the config files and disable what you don't nee...
by chrismas9
Thu Apr 02, 2020 2:38 pm
Forum: Hardware Projects
Topic: Smallest MCU for micropython
Replies: 12
Views: 634

Re: Smallest MCU for micropython

If you are new to MicroPython and don't want to learn how to port it yet you should be able to use the NUCLEO_L432KC port without modification on the QFN STM32L432KC chip. You will have to compile it as the binary is not in the downloads. It reserves 26k flash for the file system, not all of which w...
by chrismas9
Sat Mar 28, 2020 1:51 am
Forum: Hardware Projects
Topic: Smallest MCU for micropython
Replies: 12
Views: 634

Re: Smallest MCU for micropython

Also the STM32L072. Use the L073 port. This chip is memory limited (192k flash) and sometimes gets broken when new features are added. If cost is more important than size I have MicroPython running on STM32F030. It's just over $US1 in volume.
by chrismas9
Sat Mar 28, 2020 1:44 am
Forum: Hardware Projects
Topic: Smallest MCU for micropython
Replies: 12
Views: 634

Re: Smallest MCU for micropython

The STM32L432 in QFN32 is supported via the NUCLEO_L432KC port. It should be well supported because it is derived from the Pyboard port.
by chrismas9
Wed Mar 11, 2020 11:56 am
Forum: General Discussion and Questions
Topic: Custom Board - 32KHz Crystal
Replies: 2
Views: 123

Re: Custom Board - 32KHz Crystal

You don't need the 32kHz crystal. PYBLITE uses the same MCU in 64 pin package and the 32jHz crystal is optional. I suggest using a 12NHz main crystal and rely on the PLL to step it up to required frequency. If you have USB on your board you should be able to get a REPL prompt using the PYBLITE binar...
by chrismas9
Sat Feb 29, 2020 12:22 pm
Forum: MicroPython pyboard
Topic: STM32F446 vs STM32F405
Replies: 2
Views: 219

Re: STM32F446 vs STM32F405

PB11 is not available on the STM32F466. The pin requires a bypass cap for the internal core voltage regulator. It may not run reliability without this cap. You will need to start with the NUCLEO_F446 port and edit mpconfigport.h to suit your pin allocations. Make sure the PLL values match your cryst...
by chrismas9
Mon Feb 24, 2020 1:09 pm
Forum: Development of MicroPython
Topic: Slowing things down
Replies: 3
Views: 304

Re: Slowing things down

If you want to slow it down permanently, maybe to save power, you could edit the PLL values in moconfigboard.h and rebuild it. I suggest running the clock config utility in stm32cubemx to find the right values. Make sure the USB clock is still 48MHz if you are using USB.
by chrismas9
Wed Jan 29, 2020 11:43 pm
Forum: General Discussion and Questions
Topic: Help with motor control - Sorry I am just learning
Replies: 6
Views: 310

Re: Help with motor control - Sorry I am just learning

I like to learn by example. There are plenty of robot kits with sample code. Just search "micro:bit robot MicroPython". Here is one example:

https://github.com/KitronikLtd/micropyt ... cs?files=1
by chrismas9
Mon Jan 27, 2020 10:01 am
Forum: Other Boards
Topic: Boot time is 10 seconds for a NUCLEO_L452RE build
Replies: 3
Views: 457

Re: Boot time is 10 seconds for a NUCLEO_L452RE build

I just updated my build to latest, rebuilt mpy-cross, updated submodules and built NUCLEO_L452RE using WSL. the NUCLEO board boots immediately. I am using gcc 9.2.1 from ARM and WSL/UBUNTU 16.04. >>> MicroPython v1.12-96-gc3095b3 on 2020-01-27; NUCLEO-L452RE with STM32L452RE Type "help()" for more i...