Sets the data rate in bits per second (baud) for serial data transmission. For communicating with Serial Monitor, make sure to use one of the baud rates listed in the menu at the bottom right corner of its screen. You can, however, specify other rates - for example, to communicate over pins 0 and 1 with a component that requires a particular baud rate.
An optional second argument configures the data, parity, and stop bits. The default is 8 data bits, no parity, one stop bit.
Serial: serial port object. See the list of available serial ports for each board on the Serial main page.
speed: in bits per second (baud). Allowed data types:
config: sets data, parity, and stop bits. Valid values are:
SERIAL_8N1 (the default)
SERIAL_5E1: even parity
SERIAL_5O1: odd parity