DEC LA30N, User Manual

Page: 153 / 193

D-5
Interface Information
Serial Options
The serial options for the computer and the printer must match. Use the printer control
panel, the computer operating system, or your software to change options specified as
“selectable.”
Transmission mode: Asynchronous, full duplex
Speed: 600, 1200, 2400, 4800, 9600, or 19200 baud (selectable)
Data bits: 7 or 8 bits (selectable)
Parity bit: Even, odd, none, or ignore (selectable)
Start bit: 1 bit
Stop bit: 1 bit
Buffer control: XON/XOFF (DC1/DC3) or DTR (Data Terminal Ready)
(selectable)
Buffer size: 2K, 8K, 16K, 32K, or 64K bytes (selectable)
Cable Wiring
Use a null-modem cable to connect the printer to a computer terminal, as shown below:
Ready Out
Transmit Data +
Transmit Data –
Receive Data –
Receive Data +
Ready In
Host Printer
(Pin 1)
(Pin 2)
(Pin 3)
(Pin 4)
(Pin 5)
(Pin 6)
#
# indicates grounding.
(Pin 6)
(Pin 5)
(Pin 4)
(Pin 3)
(Pin 2)
(Pin 1) Ready In
Receive Data +
Receive Data –
Transmit Data –
Transmit Data +
Ready Out
#
Cable
Buffer Control
Buffer control is a communication protocol used by the computer terminal and the printer to
secure data transmission between the two devices. The buffer control ensures that the
computer does not send information to the printer faster than the information can be
processed in the printer. By telling the computer when the printer can receive data, the
buffer control prevents the printer’s buffer from overflowing.
This printer offers a choice of two different buffer controls for connection to a variety of
computers: XON/XOFF and DTR. If you computer documentation does not recommend a
particular buffer control, try DTR. The following table describes the buffer control.
#D Appendix D 23/05/96, 15:13 5