Search found 152 matches

by chrismas9
Mon Jul 12, 2021 12:06 am
Forum: Programs, Libraries and Tools
Topic: I ported my first library! MCP9600
Replies: 9
Views: 631

Re: I ported my first library! MCP9600

750pF / 4k7 has a cutoff frequency of 45kHz which is low for 100 kHz clock rate. The MCP9600 spec is 1000 ns, 300 ns for rise and fall and 250 ns setup time. It would be better to use an oscilloscope than a logic analyser and check the rise, fall and setup times. There may be differences in timing, ...
by chrismas9
Sat May 15, 2021 3:29 pm
Forum: Other Boards
Topic: [STM32L432KC] Getting MicroPython on to an STM32L432KC?
Replies: 5
Views: 1295

Re: [STM32L432KC] Getting MicroPython on to an STM32L432KC?

I use the built in STLINK interface with stmcubeprog software. It doesn't need boot0 jumpered.
by chrismas9
Sat May 15, 2021 11:20 am
Forum: General Discussion and Questions
Topic: Is MicroPython the right hammer for my nail?
Replies: 22
Views: 3685

Re: Is MicroPython the right hammer for my nail?

I use MicroPython in commercial environments and recommend it. I know if other applications including medical equipment. One of my clients who writes complex analysis software for test equipment used MicroPython for all his low level hardware control. MicroPython abstracts the machine IO enough that...
by chrismas9
Sat Aug 15, 2020 1:24 pm
Forum: Other Boards
Topic: STM32F767 partition too small
Replies: 6
Views: 1143

Re: STM32F767 partition too small

The F4 and F7 have irregular sector sizes, starting small then going to 128 KB. Most ports only allocate 64KB cache for erase write. If you want to use all the sectors you have to find contiguous RAM for a 128KB cache which will reduce your heap. There is provision to use the first half of the first...
by chrismas9
Tue Jun 02, 2020 4:48 pm
Forum: MicroPython pyboard
Topic: How to properly increase FLASH_FS on pyboardv11?
Replies: 13
Views: 9876

Re: How to properly increase FLASH_FS on pyboardv11?

uPy may report the large fs size based on numblocks, but it won't work. Have you tried filling the fs with files, then editing or replacing them? When you try to change a 512 byte sector in a 128KB flash block the whole 128KB has to be backed up in cache RAM while the block is erased. Then the new s...
by chrismas9
Sun May 31, 2020 4:22 pm
Forum: MicroPython pyboard
Topic: How to properly increase FLASH_FS on pyboardv11?
Replies: 13
Views: 9876

Re: How to properly increase FLASH_FS on pyboardv11?

You can't just keep extending the number of flash sectors on the F4 because the sectors 6 and higher are 128KB and the cache is only 64KB. There is a mechanism in flashbdev.c to use 64KB from each of sectors 6 and 7. Have a look at the F413 port which shows how to get the largest filesystem on F4. Y...
by chrismas9
Fri May 29, 2020 12:40 am
Forum: General Discussion and Questions
Topic: machine.Pin.pull_down ?
Replies: 5
Views: 2031

Re: machine.Pin.pull_down ?

When you drive an input from a push pull source you don't need a pull-up or pulldown, just a normal high impedance input. You only need a pull resistor if the driving source can become high impedance, eg open drain or tristate. If the ESP32 output is push pull, always either 0V or 3.3V, then the STM...
by chrismas9
Thu May 28, 2020 12:02 pm
Forum: Programs, Libraries and Tools
Topic: How to Build and Debug MicroPython Source Code with Eclipse
Replies: 16
Views: 16386

Re: How to Build and Debug MicroPython Source Code with Eclipse

If you install Python from the Windows Store instead of from a download it installs correctly as Python3.
by chrismas9
Mon Apr 20, 2020 1:46 am
Forum: Hardware Projects
Topic: Smallest MCU for micropython
Replies: 15
Views: 5305

Re: Smallest MCU for micropython

Thorsten, Your minimal port is similar to mine. The biggest savings come from disabling FLOAT and SPI. SPI costs about 7k. The only other big change I made was to disable the compiler. From memory this saves about 24k (my notes are at work and I am working at home). #define MICROPY_ENABLE_COMPILER (...
by chrismas9
Wed Apr 15, 2020 5:04 pm
Forum: General Discussion and Questions
Topic: Production Code for Custom Board
Replies: 9
Views: 2509

Re: Production Code for Custom Board

Once you have your code frozen it is part of the single bin, hex, elf or dfu file. You can use dfu over serial with the built in bootloader or SWD witb STLINK to program the flash and it should run. If you want to usd the filesystem as well you can setup one unit, then suck a flash image out and use...