cu
Call Up another system and act as a dial-in/serial terminal or perform file transfers with no error checking.
TLDR
Open a given serial port
$ sudo cu --line [/dev/ttyUSB0]
Open a given serial port with a given baud rate
$ sudo cu --line [/dev/ttyUSB0] --speed [115200]
Open a given serial port with a given baud rate and echo characters locally (half-duplex mode)
$ sudo cu --line [/dev/ttyUSB0] --speed [115200] --halfduplex
Open a given serial port with a given baud rate, parity, and no hardware or software flow control
$ sudo cu --line [/dev/ttyUSB0] --speed [115200] --parity=[even|odd|none] --nortscts --nostop
Exit the cu session when in connection
$ ~.