Epson 8900 Series manual Connection, ETX/ACK end-of-text/acknowledge, DTR Pin

ETX/ACK (end-of-text/acknowledge)

For this busy-handling protocol, the host sends an ETX control character at the end of each data transmission, and the printer responds with an ACK control character to indicate that it is ready to receive additional data. If the printer is busy when it receives the ETX control character, it delays sending the ACK control character until the busy condition is cleared. The default setting is OFF.

Connection

This feature provides selections for use when connecting the printer directly to the host computer or indirectly via a modem. When you connect the printer to a modem, set the connection parameter to MODEM. When you connect the printer directly to the host computer or a terminal, select DIRECT and set the busy-handling parameters to conform to the requirements of the computer. The default setting is DIRECT. The following paragraphs describe the direct connection, ready/busy protocol.

DTR (Pin 20)

For this parameter you can choose either READY HIGH or ALWAYS HIGH. For the READY HIGH setting, the printer sets interface pin 20 high to indicate that it is ready to receive data and low to indicate that it is busy. For the ALWAYS HIGH setting, pin 20 is not used for busy notification; one of the other busy-handling options must be chosen. The default setting is READY HIGH.

PIN 11

For this parameter, you can choose either READY HIGH or READY LOW. For the READY HIGH setting, the printer sets interface pin 11 high to indicate that it is ready to receive data and low to indicate that it is busy. For the READY LOW setting the printer sets interface pin 11 low to indicate that it is ready to receive data and high to indicate that it is busy. The default setting is READY LOW.

Printer Setup 2-13