Mode 3: Simplified serial.
Simplified serial mode uses TTL level RS-232 serial data to set the speed and direction of the
motor. This is used to interface the Sabertooth to a PC or microcontroller. If using a PC, a level
converter such as a MAX232 chip must be used. The baud rate is set via DIP switches.
Commands are single-byte. There is also a Slave Select mode which allows the use of multiple
Sabertooth 2x25 from a single microcontroller serial port.