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Raspberry Pi Pico 2 MicroPython problem

tonygo

I've got hold of the new Pico 2 and have tried a graphics program to make use of the extra memory. I'm using a Waveshare 2" Pico display with 320 by 240 pixels and the latest available MicroPython uf2 (v1.24.0-preview.201.g269a0e0e1 (2024-08-09) .uf2) and have hit a snag. The Waveshare display driver is included in the code and works perfectly.

To get this loop to terminate I have to include an 'unnecessary' print statement.

for i in range(r, 0, -1):
    print(i) # <==================== WHY IS THIS NEEDED? ==================
    LCD.ellipse(centre_x, centre_y,i+1, i+1,colour(i*5,i*3,i*4), 1)
    LCD.show()
    time.sleep(0.1)

If I leave it out the Pico 2 locks up at the end of the loop and if I click on the STOP icon in Thonny I get the message:


Unable to connect to COM3: could not open port 'COM3': PermissionError(13, 'Access is denied.', None, 5)

If you have serial connection to the device from another program, then disconnect it there first.

Process ended with exit code 1.

If I include the print statement it runs through to the following code as expected.

The full code can be found here:
https://pastebin.com/Fmk5iQ18

I wonder what is going on.

I know this is a 'preview' version of the UF2 but I was not expecting a problem with a counted for loop! Any ideas?

Parents
  • 0

    maybe it is some timing issue if print can be used as workaround? I wonder if replacing print with sleep would be equally effective...

  • 0 in reply to JWx 

    # Colour Mixing Routine
def colour(R,G,B): # Compact method!
mix1 = ((R&0xF8)*256) + ((G&0xFC)*8) + ((B&0xF8)>>3)
return (mix1 & 0xFF) *256 + int((mix1 & 0xFF00) /256) # low nibble first

# ==== Main ====
pwm = PWM(Pin(BL))
pwm.freq(1000)
pwm.duty_u16(32768)#max 65535

LCD = LCD_1inch3()

LCD.fill(LCD.WHITE)
LCD.show()

'''
# Set up buttons
key0 = Pin(15,Pin.IN,Pin.PULL_UP)
key1 = Pin(17,Pin.IN,Pin.PULL_UP)
key2 = Pin(2 ,Pin.IN,Pin.PULL_UP)
key3 = Pin(3 ,Pin.IN,Pin.PULL_UP)
'''
centre_x =int(LCD.width/2)
centre_y = int(LCD.height/2)
R = int((LCD.width + LCD.height)/4)
r = int((LCD.width + LCD.height)/8)
LCD.fill(0)
LCD.show()

LCD.ellipse(centre_x, centre_y,R,r,colour(255,255,0),1)
LCD.show()
LCD.ellipse(centre_x, centre_y,r,r,colour(0,0,255))
LCD.show()

for i in range(r, -1, -1):

    LCD.ellipse(centre_x, centre_y,i+1, i+1,colour(i*5,i*3,i*4), 1)
    LCD.show()
    time.sleep(0.1)

time.sleep(1)
LCD.fill(0)
LCD.show()

gc.collect
print()
print(gc.mem_free())

    There is already a time.sleep(0.1) in the loop. It did not help.

    If I comment out the button/key setup lines it works properly.

    I also tried the same code, with button setup lines on a RP2040 Pico Lipo and it works correctly.

    I think it is the UF2 for the Pico 2 causing the problem

  • 0 in reply to tonygo

    Hello! 

    if it seems to hang consistently at the end of the loop, have you tried running standalone

    LCD.ellipse(centre_x, centre_y, 2, 2,colour(2*5,2*3,2*4), 1)

    (the last value of problematic range(r, 0, -1))

    (but it will probably succeed if print in the loop remedies it).

    It is strange that it seems to be connected with certain value (when range(r, 1, -1) is ok) and timing/whatever at the same time (when print can be used as a workaround)...

  • 0 in reply to JWx

    I do not think it is my loop. If I comment out the Button setup lines it works perfectly even with 

    for i in range(r, -1, -1):

    controlling the loop.

    I've run the full code, including the button setup, with a Pimoroni Pico Lipo (RP2040) and it works perfectly. You are supposed to be able to just substitute a Pico 2 for a Pico 1 and the same code should work.

    I think the new Pico 2 .UF2 is the problem.

    Once again the hardware is available ahead of the essential software as a proper release is not yet available. The current version is a preview (9th Aug 2024).

Reply
  • 0 in reply to JWx

    I do not think it is my loop. If I comment out the Button setup lines it works perfectly even with 

    for i in range(r, -1, -1):

    controlling the loop.

    I've run the full code, including the button setup, with a Pimoroni Pico Lipo (RP2040) and it works perfectly. You are supposed to be able to just substitute a Pico 2 for a Pico 1 and the same code should work.

    I think the new Pico 2 .UF2 is the problem.

    Once again the hardware is available ahead of the essential software as a proper release is not yet available. The current version is a preview (9th Aug 2024).

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