79
1: INTERFACES
Handshake:
DSTB to printer and BUSY to host.
Interface cable
Computer end:
Depends on type of host computer.
IBM-PC: DB25 male connector.
Printer end:
36-p male Centronics connector.
Pin
Function
Transmitter
1
-Strobe
Host
2–9
Data 0–7
Host
10
Busy
Printer
11
Busy
Printer
12
Paper empty
Printer
13
Select
Printer
14–15
N/C
16
Signal ground
17
Chassis ground
18
N/C
19–30
Signal ground
31
-Init
32
-Fault
Printer
33
Signal ground
34–36
N/C
Protocol (default):
9600 baud, No parity, 8 data bits, 1 stop bit
XON/XOFF, DSR/CTS
To change serial settings, use the Y command, see page 41.
Interface cable
Computer end:
Depends on type of host computer.
IBM-XT & PS-2: DB25 female connector.
IBM-AT: DB9 female connector
Printer end:
DB9 male connector.
Host
9-pin
25-pin
9-pin
Printer
1
+5V
RXD
2
3
2
TXD
TXD
3
2
3
RXD
DTR
4
20
4
N/C
GND
5
7
5
GND
DSR
6
6
6
RDY
RTS
7
4
7
N/C
CTS
8
5
8
RDY
9
N/C
Parallel Interface
Serial Interface (RS 232C)
UBI EasyCoder 71 – Appendices