Appendix A System Interface Description

1.2Transmission Protocols and Connection Diagrams

1.2.1DTR - Ready/Busy

(Supported RS-232C Protocols) - Full Duplex Local Connection

This protocol uses the following signal lines:

S Pin

1 Protective Ground (PG)

S2 Transmit Data (TXD)

S3 Receive Data (RXD)

S5 Clear to Send (CTS)

S7 Signal Ground (SG)

S20 Data Terminal Ready (DTR)

Note: The signal lines TXD (pin 2) and CTS (pin 5) are only necessary if the Device Status Report is required.

The READY / BUSY DTR protocol uses the DATA TERMINAL READY (DTR) line to control the transmission of data from the host to prevent a buffer overflow.

Note: Printer DTR may be connected to host DSR + CTS or only to host DSR and a bridge between RTS and CTS.

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Epson C I - 4 0 4 0, C I - 4 0 5 0 user manual Appendix a System Interface Description