Epson Stylus COLOR 670 Service Manual page 16

EPSON Stylus Color 670
Table 1-4. 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 -
NOTE: * A low logic level on the Logic H signal is 2.0 V or less when
the printer is 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 7.5 K ohm to ground.
Table 1-5. Connector Pin Assignment and Signals (F-Channel)
Pin Signal Return
In/Out
No. Name GND Pin
1 -STROBE 19
2 DATA0 20
Product Description
Maximum Condition
5.5V
-
0.32mA VOH=2.4V
12mA VOL=0.4V
50pH
2.0V
-
0.32mA VIH=2.0V
12mA VIH=0.8V
50 pF
Function Description
The strobe pulse. Read-in of data is
In performed at the falling edge of this
pulse.
The DATA0 through DATA7 signals
represent data bits 0 to 7, respectively.
In Each signal is at high level hen data is
logical 1 and low level when data is
logical 0.
Table 1-5. Connector Pin Assignment and Signals (F-Channel)
Pin Signal Return
No. Name GND Pin
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
35 +5V
Interface
In/Out Function Description
In
In
In
In
In
In
In
This signal is a negative pulse
Out indicating that the printer can again
accept data.
A high signal indicated that the printer
Out
cannot receive data.
A high signal indicates paper-out
Out
error.
Always at high level when the printer
Out
is powered on.
In Not used.
The falling edge of a negative pulse or
a low signal on this line causes the
In
printer to initialize. Minimum 50 us
pulse is necessary.
A low signal indicates printer error
Out
condition.
In Not used.
- Out Pulled up to +5V via 3.9K ohm resistor.
- Out Pulled up to +5V via 3.3K ohm resistor.
Revision A
16