Follow these instructions to install the serial port module.
With the DC power plug and module’s access door removed, slide the serial port module into the printer. Push the circuit card in slowly but firmly until the card is just past the inside lip of the access door.
Align the bottom of the serial port’s door cover to the bottom lip of the module access opening. Swing the door up and snap the cover closed.
Serial port (RS-232)
For best printer performance, update the printer’s firmware after installing options or immediately after the printer’s initial setup. See Updating Printer Firmware.