BBC micro:bit - Radio string transfer random carriage returns

Question

I have two BBC Micro Bit and using Radio function to transfer data from one slave to the master Micro Bit. When the data is transferred I am getting random carriage returns, I am not sure what is the problem, I have tried to strip any random CR etc, but still getting the same problem.

a=1,On,

12

=2,

Off, 77

=3,

On, 88

===================================================

Gateway code

from microbit import *
import radio

radio.config(group=0)
radio.on()

while True:
   incoming = radio.receive()
   if incoming:
      uart.write(incoming)  

==============================================

Slave code

from microbit import *
import radio

radio.config(group=0)
radio.on()

while True:
  if button_a.was_pressed():
      radio.send('Matt,A=On,Off' + '\n')  # a-ha
      display.scroll("A")

  if button_b.was_pressed():
      radio.send('Matt,B=On,Off' + '\n')  # a-ha
      display.scroll("B")

=========================================================

PySerial code

import sys
import glob  
import serial


def serial_ports():
    ports = ['COM%s' % (i + 1) for i in range(256)]

result = []
for port in ports:
    try:
        s = serial.Serial(port)
        s.close()
        result.append(port)
    except (OSError, serial.SerialException):
        pass
return result


if __name__ == '__main__':
  print(serial_ports())
try:
ser = serial.Serial('COM5', 115200, timeout = 0)
print("connected to: " + (ser.portstr))
except serial.SerialException:
pass

while True:
line = ser.readline().decode('utf-8')
# Read a line and convert it from b'xxx\r\n' to xxx 

if line:  # If it isn't a blank line
    f = open('output.csv', 'a+')
    f.write(line + '\n')
    print(line)
    f.close()

ser.close()

Answer 1

I found your scripts worked without sending extra carriage returns. I tested using two microbits. I used the REPL in mu and also CoolTerm, set to 115200 baud. I am using Linux Mint as my OS. CoolTerm output: Matt,B=On,Off Matt,A=On,Off

Added after the pyserial code was posted: The code below works for me to produce the expected output without extra blank lines. The newline is removed by using the end='' in the print statement. Finding the microbit using the pid and vid enables you to have other serial devices attached. Credit to microbit-playground for posting example code on how to use pid and vid to find the microbit.

I tested this on Linux using the jupyter notebook. It should work on Windows without modification.

import serial
import serial.tools.list_ports as list_ports

def find_microbit_comport():
    ports = list(list_ports.comports())
    for p in ports:
        if (p.pid == 516) and (p.vid == 3368):
            return str(p.device)

if __name__ == '__main__':
    ser = serial.Serial()
    ser.baudrate = 115200
    ser.port = find_microbit_comport()
    ser.open()

while True:
    line = ser.readline().decode('utf-8')
    if line:  # If it isn't a blank line
        f = open('output.csv', 'a+')
        f.write(line)
        print(line, end='')
        f.close()

ser.close()