7.3.4 Optional Serial Interface RS232C
Your printer’s serial interface supports the RS232C specification. The signals are received
and transmitted by a 9 pin connector.
Basically 3 lines are enough for exchanging information between computer and printer (one
receive line, one send line, one line for common grounding).
OFF (log.1) -3 V to -15 V
ON (log. 0) +3 V to +15 V
ITT Cannon connector, series DB-9 S
XON/XOFF, ENQ/STX, READY/ BUSY,
Robust XON/XOFF, ETX/ ACK, ACK/NAK
512Byte min. 256KByte max