I wanted to make a scrolling display for my desk on parents’ evening, and thought I might use a micro:bit. Then I thought 5 micro:bits might be even better. But how to get them scrolling one message across? I didn’t want to use a computer to control them, I wanted them to be standalone, self-contained. And the radio abilities of the micro:bit mean that no wires should be needed.
So here’s a very simple bit of Python that will turn any number of micro:bits into a rough and ready big scrolling display. There are two different programs, one for the transmitting micro:bit which goes on the right-hand end. Code your message into the Python script and flash it using the Mu editor. When all your other micro:bits are ready, press button A to begin.
-------------------- |RX4|RX3|RX2|RX1|TX| --------------------
The receiver code goes on all the other micro:bits numbered 1 upwards, lower numbers on the right. Change the number for each device. When powered up they stay blank until they receive the message from the transmitter.
Transmitter code – this goes on the micro:bit on the far right. Code your message in here:
from microbit import * import radio message = 'Mr Booth - ICT' while True: if button_a.was_pressed(): radio.on() radio.send(message) while True: display.scroll(message)
Here’s the receiver code – change the rxnumber for the device number, numbering from 1 on the right, higher numbers as you go left:
from microbit import * import radio radio.on() # set the receive device number here rxnumber = 1 sleeptime = rxnumber * 750 while True: incoming = radio.receive() if incoming: sleep(sleeptime) while True: display.scroll(incoming)
Unbeknown to me, Philip Meitiner of the micro:bit Educational Foundation has been working on pretty much exactly the same idea! Can’t wait to see his code as I suspect his is a much more elegant solution:
— Philip Meitiner (@pragmaticPhil) November 5, 2017