Epson 680Pro - LQ B/W Dot-matrix Printer Service Manual page 15

EPSON Stylus COLOR 680/777/777i
Table 1-4. Typical Time of tack
Parallel I/F Mode
High Speed
Normal Speed
Table 1-5. Signal Level: TTL Compatible (IEEE-1284 level 1 device)
Parameter Minimum
VOH* -
VOL* -0.5V
IOH* -
IOL* -
CO -
VIH -
VIL 0.8V
IIH -
IIL -
CI -
* A low logic level on the Logic H signal is 2.0V or less when the printer
is powered off, and this signal is equal to or exceeding 3.0V when the
printer is powered on. The receiver shall provide an impedance
equivalent to 7.5K ohm to ground.
PRODUCT DESCRIPTION
Typical Time of tack
0.5us
2us
Maximum Condition
5.5V
-
0.32mA VOH = 2.4V
12mA VOL = 0.4V
50pF
2.0V
-
0.32mA VIH = 2.0V
12mA VIL = 0.8V
50pF
INTERFACE
Table 1-6. Connector Pin Assignment and Signals
Return
Pin No. Signal Name
GND Pin
1 -STROBE 19
2 DATA0 20
3 DATA1 21
4 DATA2 22
5 DATA3 23
6 DATA4 24
7 DATA5 25
8 DATA6 26
9 DATA7 27
10 -ACKNLG 28
11 BUSY 29
12 PE 28
13 SLCT 28
14 -AFXT 30
31 -INIT 30
32 -ERROR 29
36 -SLIN 30
18 Logic H -
Revision B
In/Out Functional Description
The strobe pulse. Read-in of data is
In performed at the falling edge of this
pulse.
In
In
In
The DATA0 through DATA7 signals
represent data bits 0 to 7, respectively.
In
Each signal is at high level when data is
In
logical 1 and low level when data is
logical 0.
In
In
In
This signal is a negative pulse indicating
Out
that the printer can accept data again.
A high signal indicates that the printer
Out
cannot receive data.
Out A high signal indicates paper-out error.
Always at high level when the printer is
Out
powered on.
In Not used.
The falling edge of a negative pulse or a
low signal on this line causes the printer
In
to initialize. Minimum 50us pulse is
necessary.
A low signal indicates printer error
Out
condition.
In Not used.
Out Pulled up to +5V via 3.9 K ohm resistor.
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