Communications interface, Parallel interface – TransAct Technologies ITHERM 280 User Manual
Page 32

Specifications and Requirements
iTherm
®
280 Programmer’s Guide
Page 30
Rev C
28-07764
Communications Interface
Parallel Interface
Your printer features two parallel interfaces:
•
An IEEE 1284-A 25-pin, D-shell connector, with pin-outs that interface to a
standard IBM PC parallel printer interface with a one-to-one cable.
•
An IEEE 1284-B, which is a standard Centronics 36-pin connector.
Both interface cards provide a dual cash drawer interface. The following table lists
interface signals and corresponding pins.
25-pin Connector
36-pin Connector Signal
Description
Direction
Pin 1
Pin 1
STROBE
Clock data to printer
Host to Printer
Pins 2-9
Pins 2-9
D0 - D7
Data
Host to Printer
Pin 10
Pin 10
ACK\
Printer accepted data
Printer to Host
Pin 11
Pin 11
BUSY
Printer busy
Printer to Host
Pin 12
Pin 12
PE
Paper Out/Status
Printer to Host
Pin 13
Pin 13
SLCT
Printer selected
Printer to Host
Pin 14
Pin 14
AUTOFD
Autofeed paper
Host to Printer
Pin 15
Pin 32
FAULT\
Printer error
Printer to Host
Pin 16
Pin 31
INIT\
Initialize printer
Host to Printer
Pin 17
Pin 36
SLIN
Select printer
Host to Printer
Pin 17
FG
Frame ground
Printer to Host
-
Pin 18
+5V
Peripheral logic high
Printer to Host
Pins 18-25
Pins 16, 19-30
GND
Ground
Table 4 Parallel Interface Pin-outs
Signal Levels
Voltage levels
0 V and +5 V (nominal)
Logic levels
Logic one
Driver
+2.4 V to +5 V
Receiver
+2.0 V to +5 V
Logic zero
Driver
0 V to +0.4 V
Receiver
0 V to +0.8 V
Current requirements
Logic one
Source
0.25 ma at +2.4 V
Logic zero
Sink 16 ma
Line termination
Data and control
3.3k ohm to +5 V
Strobe
1.2k ohm to +5 V