set Baud Rate

Set the baud rate of the serial connection.


The baud rate of the serial connection is the speed at which it will transmit data. You can set one of several standard rates for the transmit speed. The receiving micro:bit or device must be set to receive data at the same speed as the sending micro:bit.

Bits and bauds

Baud, or baud rate, is a very old measure of data speed. It originates from the early days of teletype when characters of the alphabet were transmitted over telegraph wires. Signal changes on the wires are used to encode a sequence of bits that represented a character in a message. The baud rate is how many times per second these signal changes happen. When binary data (digital bits) is transmitted over an analog system, like telegraph or telephone wires, the bits are modulated by a signal changing scheme to represent them. Sometimes mutliple bits are transmitted in a signal change which makes the actual bit rate faster than the baud rate.


  • rate: The baud rate to set for the serial connection. The default rate is 115200 baud, The rates to choose from are:
    • 1200 baud
    • 2400 baud
    • 4800 baud
    • 9600 baud
    • 14400 baud
    • 19200 baud
    • 28800 baud
    • 31250 baud
    • 38400 baud
    • 57600 baud
    • 115200 baud

Logging serial data

In order for the serial console log to record your serial data, the baud rate MUST remain at 115200 (the default).


Set the baud rate to 9600 and send a message over USB serial to a computer.

serial.writeString("This is my SERIAL message!")

See also