Interface Card

The C823051 serial interface card

If you are using an optional interface, it may be necessary for you to alter the communication protocol of the printer or computer so they can communicate properly. In most cases, you should use the information in your optional interface manual or your computer’s manual to match the computer with the interface.

If you are using the C823051 optional interface card with your printer, make sure that you read through the section below on baud-rate selection. You may also want to refer to the section on handshake timing and error handling for interface information specific to your printer.

For all other data transfer conventions, such as word structure or communications protocol, see the manual supplied with your C823051 optional interface.

Baud rate selection

You can select from the following baud rates: 150, 300, 600, 1200, 2400, 4800, 9600, and 19,200 bps (bits per second). When you set the baud rate, see the baud rate selection table in the C823051 interface manual.

Handshake timing

When the vacant area for data in the input buffer drops to 256 bytes, the printer outputs an X-OFF code or sets the DTR flag to “1” (MARK) indicating that it cannot receive data.

Once the vacant area for data in the buffer increases to 528 bytes, the printer outputs an X-ON code or sets the DTR flag to “0” (SPACE) indicating that it is again ready to receive data.

Error handling

When a parity error is detected, your printer prints an asterisk (*). All other errors, including framing and overrun errors, are ignored.

4-18 Using the Printer Options