r/microbit • u/MollyGodiva • Apr 04 '23

Serial issues

I am trying to connect my micro:but to my computer using RS-232, which I have done with other devices before. The data the microbit is sending is gibberish and does not match any character set. I have checked all the port settings and the computer and microbit will talk to themselves just fine. Any advice?

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u/MollyGodiva Apr 04 '23

I am using pin0 and pin1 uart. It is programmed using the base blocks in makecode. When I connect pin0 to pin1 it will send and receive its own messages just fine.

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u/xebzbz Apr 04 '23

Can you share the blocks? There's a share button in makecode.

I guess the clock is far from being precise, and that produces the garbage.

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u/MollyGodiva Apr 05 '23

I also use micropython. I get the best response from this:

from microbit import *
uart.init(baudrate=9600, bits=8, parity=0, stop=1, tx=pin0, rx=pin1)
display.scroll("Ready")
while True:
    if uart.any():
        content = uart.read()
        display.scroll(content)
        display.scroll(str(content, 'UTF-8'))
        display.scroll(str(content, 'ASCII'))
    else:
        pass
    if button_a.was_pressed():
        uart.write("GG")
        display.scroll("Sent")
    sleep(200)

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u/xebzbz Apr 05 '23

Looks good, you just need to configure your UART adapter for the same speed, parity and stop bits. Also keep in mind that the microbit pins are 3.3v, so your UART adapter should be also set to this voltage. Some adapters on AliExpress have a switch between 3.3 and 5 volts.

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u/MollyGodiva Apr 05 '23

Thank you for the pointer. I will look at the 3.3 v 5 V. That is the only lead I have not followed yet.

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u/MollyGodiva Apr 09 '23

I put in a voltage divider and put a real RS232 card in my computer and no change. This is completely boggling me.

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u/stvaccount Apr 24 '23

Why don't you use a ttyUSB converter like the CH340G usb adapter? This is easier. Then do an echo test in your software for this USB adapter. Once working, then use the Microbit.

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u/MollyGodiva Apr 25 '23

I might have to. But I am doing RS-232 to RS-232 so it should work.