Epson LQ 1050 - B/W Dot-matrix Printer - DIP Switch Circuit and Jumpers

2.3.4.3 DIP Switch Circuit
The printer has two types of
REV.-A
and Jumpers
DIP switches and two jumpers. Figure 2-31 shows the DIP switch circuit.
+5V
1
I
RM 1
1
PBO
1
CPU :
(781OHG)
4
(46) :
7
AN3
4
CN 1
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PA?
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36 m
PA6
M
- 14 AUTO
FEtD XT
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IK
k
J1
SW2-4
Figure 2-31. DIP Switch Circuit
DIP switch settings are read by the DIP switch circuit whenever the printer power is turned on and
whenever the INIT signal is sent to the printer from the host computer.
Jumpers
There are two jumpers on the PEGX board.
J 1: Determines whether or not the internally fixed printer selection signal
(SLCTIN) is selected by the
host computer.
When jumper J 1 is connected, the
SLCTIN signal is internally fixed (always selected).
J2: Switches the memory capacity (5
12K bits or 256K bits) for the PROM (IC4A).
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