Epson Stylus Color C70, Service Manual

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EPSON Stylus COLOR C70/C80 Revision A
PRODUCT DESCRIPTION INTERFACE 16
NOTE: (*) A low logic level on the Logic H signal is 2.0V or less when the
printers powered off and this signal is equal or exceeding 3.0V when
the printer is powered on. The receiver shall provide an impedance
equivalent to 7.5K ohm to ground.
z
NOTE: In/Out refers to the direction of signal flow from the printer’s point of
view.
Table 1-6. Typical Time of tack
Parallel I/F Mode Typical Time of tack
High Speed 0.5us
Normal Speed 2us
Table 1-7. Signal Level: TTL Compatible (IEEE-1284 level 1 device)
Parameter Minimum Maximum Condition
VOH* - 5.5V
VOL* -0.5V -
IOH* - 0.32mA VOH = 2.4V
IOL* - 12mA VOL = 0.4V
CO - 50pF
VIH - 2.0V
VIL 0.8V -
IIH - 0.32mA VIH = 2.0V
IIL - 12mA VIL = 0.8V
CI - 50pF
Table 1-8. Connector Pin Assignment and Signals
Pin No. Signal Name
Return
GND Pin
In/Out Functional Description
1 -STROBE 19 In
The strobe pulse. Read-in of data is performed at
the falling edge of this pulse.
2 DATA 0 20 In The DATA 0 through DATA 7 signals represent
data bits 0 to 7, respectively.
Each signal is at high level when data is logical
1 and low level when data is logical 0.
3 DATA 1 21 In
4 DATA 2 22 In
The DATA 0 through DATA 7 signals represent
data bits 0 to 7, respectively.
Each signal is at high level when data is logical
1 and low level when data is logical 0.
5 DATA 3 23 In
6 DATA 4 24 In
7 DATA 5 25 In
8 DATA 6 26 In
9 DATA 7 27 In
10 -ACKNLG 28 Out
This signal is a negative pulse indicating that the
printer can accept data again.
11 BUSY 29 Out
A high signal indicates that the printer cannot
receive data.
12 PE 28 Out A high signal indicates paper-out error.
13 SLCT 28 Out
Always at high level when the printer is
powered on.
14 -AFXT 30 In Not used.
31 -INIT 30 In
The falling edge of a negative pulse or a low
signal on this line causes the printer to initialize.
Minimum 50 us pulse is necessary.
32 -ERROR 29 Out A low signal indicates printer error condition.
36 -SLIN 30 In Not used.
18 Logic H - Out Pulled up to +5V via 3.9 K ohm resistor.
35 +5V - Out Pulled up to +5V via 3.3K ohm resistor.
17 Chassis GND - - Chassis GND
16,33,
19-30
GND - - Signal GND
15,34 NC - - Not connected
Table 1-8. Connector Pin Assignment and Signals (continued)
Pin No. Signal Name
Return
GND Pin
In/Out Functional Description