Epson 890N - FX B/W Dot-matrix Printer, Service Manual

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EPSON FX-890/2190 Revision B
PRODUCT DESCRIPTIONS Interface 23
1.2 Interface
This printer provides bi-directional 8-bit parallel interface, USB interface and Type-B
optional interface slot as standard.
1.2.1 Parallel interface (Forward channel)
†
Specifications
„
Transmission mode: 8 bit parallel, IEEE-1284 compatibility mode
„
Adaptable connector: 57-30360 (Amphenol) or equivalent
„
Synchronization: -STROBE pulse
„
Handshaking : BUSY and -ACKNLG signals
„
Signal level: TTL compatible (IEEE-1284 level 1 device)
Note : In/Out shows the direction of signal flow from the printer’s point of view.
Table 1-25. Connector pin assignment (Forward channel)
Pin
No. Signal
Name
Return
GND
Pin
IN/
Out*
Function description
1 -STROBE 19 In
Strobe pulse. Input data is latched at falling edge of
the signal.
2 DATA1 20 In Parallel input data to the printer. bit 0: LSB
3 DATA2 21 In bit 1
4 DATA3 22 In bit 2
5 DATA4 23 In bit 3
6 DATA5 24 In bit 4
7 DATA6 25 In bit 5
8 DATA7 26 In bit 6
9 DATA8 27 In bit 7: MSB
10 -ACKNLG 28 Out
This signal (negative pulse) indicates that the
printer has received data and is ready to accept next
one.
11 BUSY 29 Out
This signal’s high level means that the printer is not
ready to accept data.
12 PE 28 Out
This signal’s high level means that the printer is in
a state of paper-out error.
13 SLCT 28 Out
Always at high level when the power to the printer
is on.
14 -AFXT 30 In Not used.
31 -INIT 30 In This signal’s negative pulse initializes printer.
32 -ERROR 29 Out
This signal’s low level means the printer is in a
state of error.
36 -SLIN 30 In Not used.
18 Logic H - Out
This line is pulled up to +5 V through 3.9 k
Ω
resistor.
35 +5 V - Out
This line is pulled up to +5 V through 1.0 k
Ω
resistor.
17 Chassis - - Chassis GND.
16, 33
19-30
GND - - Signal GND.
15, 34 NC - - Not connected.
Table 1-25. Connector pin assignment (Forward channel) (continued)
Pin
No. Signal
Name
Return
GND
Pin
IN/
Out*
Function description