Star Micronics LC-8521, Technical Manual

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ACK
Data
STROBE
(EDS B-6 : ON)
STROBE
(EDS B-6 : OFF)
BUSY
4
µ
s
t : More than 0.5
µ
s
4
µ
s
t t t t
4. Parallel Interface
4-1. General Specifications
Item Specifications
Interface Centronics-compatible
Synchronization System Via externally supplied STROBE pulse
I/F Protocol Using ACK and BUSY signals
Logic Level Compatible with TTL level
These signals represent information for the 1st through 8th bit of
parallel data, respectively. Each signal is HIGH when data is logical 1,
and LOW when logical 0.
Fig. 1-6 Timing Charts for Parallel Interface
4-2. Connector Signals
Pin Name Function
1 STROBE Goes low for
≥
0.5
µ
s when active.
2 DATA0
3 DATA1
4 DATA2
5 DATA3
6 DATA4
7 DATA5
8 DATA6
9 DATA7
10 ACK 10
µ
s low to acknowledge receipt of data.
11 BUSY Printer sets line low when ready to receive data.
12 PAPER High when paper runs out.
13 SELECT High when printer is on-line.
14 AFXT Printer ignores this signal.
15 Not used.
16 SIGNAL GND Signal ground
17 CHASSIS Chassis ground (isolated from signal ground)
18 +5V +5V DC output from printer
19~30 GND Twisted pair ground return
31 RESET Printer is reset when this signal goes low.
32 ERROR Low when printing cannot continue due to error.
33 EXT GND External ground
34~35 Not used
36 SELECT IN Printer ignores this signal.