Serial Interface

The printer’s resident serial interface can be set for RS-232C operation. This interface has the following characteristics:

Data format

Word length:

7 or 8 bits

Parity:

None, odd or even

Stop bits:

1 or 2

Printer ready protocol:

Enabled (XON/XOFF protocol set to

 

ON)

Baud rate (bits per second):

300 to 115,200

Note:

When using the serial interface as RS-232C, the awailability of baud rates over 38400 depends on your computer’s hardware reliability (including the interface cable). Also, set the XON/XOFF protocol on OFF and use DTR/DSR control. EPSON does not recommend or guarantee the use of any particular brand of computer.

Signal level: RS-232C:

Conformes to EIA

Connector

D-sub 25-pin or 9-pin connector (computer)/D-sub 25-pin. (printer)

Handshaking

The printer’s default serial interface settings can use DTR (Data Terminal Ready) signal levels and XON/XOFF communication protocols, either separately, or in combination. When the vacant area for data in the input buffer drops to 256 bytes, the printer outputs an XOFF code or sets the DTR signal level to low (MARK), indicating that it cannot receive more data.

Once the vacant area for data in the buffer recovers to 512 bytes, the printer outputs the XON code or sets the DTR flag to high (SPACE), indicating that it is again ready to receive data.

When using a baud rate of 38400 or higher in communications, set the XON/ XOFF protocol on OFF and set both DTR and DSR on ON and use DTR/DSR control. If the communications speed is fast, the interval for sending of XON/ XOFF signals becomes shorter and the computer may noto be able to process them. In addition, if you have changed this setting, change the computer’s serial interface settings also.

A-12Technical Specifications