Epson LQ-300 - Impact Printer, Service Manual

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Service Manual Product Description
1.3.1.2 Reverse Mode
reverse mode supports nibble mode, described in this section.
Transmission mode: nibble mode
Signal level:
level 1 device
Adaptable connector:
36-pin 57-30360 or equivalent
Table 1-14. Signal and Connector Pin Assignments for Parallel Interface
Pin No. Signal Name
Description
1 19
In
Host clock signal.
2-9 20-27
In
Signals through DATA7 represent data
bits O to 7.
10 28 out Printer signaL
11
PtrBusy /
29
Printer busy signal and reverse channel transfer
data bit 3 or 7.
12
AckDataReq
28
Acknowledge data request signal and reverse
DataBit-2,6
channel transfer data bit 2 or 6.
13
I
28
X-flag signal and reverse channel transfer data
DataBit-l,5
bit 1 or5.
14
HostBusy
30
In Host busy signal.
15 NC
— —
Not
16
. —
Signal ground.
17 Chassis
— —
Chassis ground.
18 Logic-H
—
o u t Pulled up to +5 via 3.9K resistor.
—
—
Signal ground.
31
In Not used.
32
DataAvail
29
Data available signal and reverse channel
DataBit-0,4
transfer bit O or 4.
33
— —
Signal ground.
34 NC
—
—
Not
35
+5
—
o u t Pulled up to +5 via 3.3K S2 resistor.
36
1284-Active
30
In 1284 active signal.
The l/O column indicates the direction of the signal as viewed from the printer.
Rev. A 1-13