MicroPython on STM32F407G-DISC1: Difference between revisions

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'''What Can I Do with MicroPython and the STM32F407G-DISC1 Discovery Board?'''<br>
'''What Can I Do with MicroPython and the STM32F407G-DISC1 Discovery Board?'''<br>
Let's begin with some simple exercises...
Let's begin with some simple exercises...
  '''# Blink LEDs (blinky1.py)'''
'''Turn Blue LED on and off'''
blue=pyb.LED(4)
blue.on()
blue.off()
The above exercise, entered via the REPL interpreter, will create an LED object, called "'''blue'''"<br>
and then call the LED member function '''on()''', and '''off()'''<br>
 
  '''# Blink Four LEDs (blinky1.py)'''
  # LED color vs number: 1: red, 2: green, 3: orange, 4: blue
  # LED color vs number: 1: red, 2: green, 3: orange, 4: blue
  import pyb
  import pyb

Revision as of 11:49, 24 April 2021

MicroPython, https://micropython.org/, a subset of the popular Python 3 programming language, is available to run on many development boards, including a large selection from STMicro.
The original development platform for MicroPython is the Pyboard, using an STM32F405RG microcontroller with 168 MHz Cortex M4 CPU, hardware floating point, 1024KiB flash ROM, and 192KiB RAM.
https://store.micropython.org/product/PYBv1.1H

Due to its feature set, lower price, and additional hardware, I chose the {{#if:|{{#ifexpr:({{#time:U|{{{3}}}}} - {{#time:U|now}}) > 0|STM32F407G-DISC1 Discovery Board|STM32F407G-DISC1 Discovery Board}}|STM32F407G-DISC1 Discovery Board}}, https://www.st.com/en/evaluation-tools/stm32f4discovery.html, for $19.50.
Although many of the associated web pages use the DFU loader to program the MicroPython image into the microcontroller,
I chose to use the on-board JTAG adapter, making this a very easy two step process:

* After downloading the image, convert the .DFU image to .HEX using the DFU File Manager (Part of the DfuSe package).
  https://www.st.com/en/development-tools/stsw-stm32080.html
* Using STM32CubeProgrammer, write the .HEX file to the STM32F407G target processor.
  https://www.st.com/en/development-tools/stm32cubeprog.html

MicroPython with the STM32F407G-DISC1 Discovery Board creates a USB Virtual COM Port as well as a USB Drive when connected to a Host computer.
Files may be added (or modified) within the PYBFLASH drive.
Use TeraTerm, Putty, or other serial terminal program to connect to the USB Virtual COM Port

What Can I Do with MicroPython and the STM32F407G-DISC1 Discovery Board?
Let's begin with some simple exercises...

Turn Blue LED on and off
blue=pyb.LED(4)
blue.on()
blue.off()

The above exercise, entered via the REPL interpreter, will create an LED object, called "blue"
and then call the LED member function on(), and off()

# Blink Four LEDs (blinky1.py)
# LED color vs number: 1: red, 2: green, 3: orange, 4: blue
import pyb
msdelay = 300 # ms delay
# Create list of LED objects in the order you wish to have them blink
leds = [pyb.LED(3),pyb.LED(1),pyb.LED(4),pyb.LED(2)]
while True:
    for i in range(4):
        leds[i].on()
        pyb.delay(msdelay)
        leds[i].off()

The above text may be copied - paste into a file, blinky1.py, on the PYBFLASH drive
At the REPL prompt, enter:
>>> import blinky1
That will cause the file, blinky1.py, to be loaded and executed
- Use control-C  ^C  to break from loop and return to REPL interpreter