Canon MultiPASS C50 Service Manual page 231

Connector signals
The following table lists the signals and input/output status of the pin assignments used for parallel
communication.
Pin No. Signal
1 -STROBE
2 DATA1
3 DATA2
4 DATA3
5 DATA4
6 DATA5
7 DATA6
8 DATA7
9 DATA8
10 -ACKNLG
11 BUSY
12 P.E.
13 SELECT
14 -AUTO FEED XT*2
15 No Connection
16 GND
17 GND
18 +5V*4
* 1 . All -RETs are connected to GND.
* 2 . These signals are valid only in Epson LQ mode.
* 3 . This signal is connected to +5.0V via 3.3k resistor.
* 4 . The level is raised to +5V at 390 resistor.
Signal descriptions
-STROBE
When the printer receives a low -STROBE pulse of width greater than 0.5µs from the computer, it reads
the data from the interface and makes the BUSY line high.
DATA
These signals are the 8 bits of parallel data from the computer. A high level indicates a logical 1; a low
level, a logical 0. The printer reads the DATA lines when a -STROBE pulse is received.
-ACKNLG
The ACKNLG pulse tells the computer that the printer has read the data from the previous -STROBE
pulse. An -ACKNLG pulse is also generated when the printer is powered on, or at the completion of
printer initialization by an -INIT signal requested from the computer.
I/O Pin No.
Input 19 -STROBE -RET*1
Input 20 DATA1 -RET
Input 21 DATA2 -RET
Input 22 DATA3 -RET
Input 23 DATA4 -RET
Input 24 DATA5 -RET
Input 25 DATA6 -RET
Input 26 DATA7 -RET
Input 27 DATA8 -RET
Output 28 -ACKNLG -RET
Output 29 BUSY -RET
Output 30 P.E. -RET
Output 31
Input 32 -ERROR
33
34 No Connection
35 +5.0V*3
Output 36 -SLCT IN*2
1-7
Chapter 1: General Description
Signal I/O
-INIT Input
Output
GND
Output
Input