Interface Specifications

Handshaking

The printer’s serial interface can use DTR (Data Terminal Ready) signal levels and XON/XOFF communication protocols either separately or in combination

XON/XOFF protocol

When the vacant area for data in the input buffer drops to 128 bytes, the printer outputs an XOFF code, indicating that the printer cannot receive more data. Once the vacant area for data in the buffer recovers to 256 bytes, the printer outputs an XON code, indicating that the printer is again ready to receive data.

XON/XOFF protocol can be enabled using SelecType. The factory setting is “ENABLE.”

DTR/DSR protocol

When the printer can receive the data, the printer sets the DTR signal level to high (SPACE). When the printer cannot receive data, the printer sets the DTR signal level to low (MARK). If the DTR menu in SelecType is set to off, the DTR signal is always treated as high (SPACE.) The printer sends the TXD (transmitted data) only when the DSR signal level is set to high (SPACE) except the DSR menu in SelecType is set to off. If the DSR menu in SelecType is set to off, the DSR signal is always treated as high (SPACE.)

DTR/DSR protocol can be enabled using SelecType. The factory settings are DTR “ON” and DSR “OFF.”

Error handling

A * character is printed if a parity error, framing error, or over-run error is detected.

8-18 Technical Specifications