DX7_8X_EXP
Page 4 of 6
Install v2.22
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Preliminary
Remove the EPROM and SRAM ICs
The next step is to
remove
the EPROM and two SRAM
ICs
.
The EPROM is found in
location IC14 and the two
M5M5118P SRAM chips are
located at IC21 and IC20.
Remove
them
by
prying
slowly at each end of the chip
back-and-forth with a small
flat-head screwdriver. Avoid
touching any of the metal pins
with the screwdriver.
Place them safely aside on
anti-static foam. You can use
the reverse side of the foam
shipped with the DX7-8X-
EXP.
The photo above shows the 3 chips removed.
Install the DX7_8X_EXP Wiring
FOLLOW THE INSTALLATION STEPS EXACTLY.
Do NOT install the circuit board at this time!
Carefully unplug the 3-conductor cable from
the DX7_8X_EXP board and set the board
aside. The 3 wires that make up this cable
need to be soldered onto chips that are
already present on the DX7 main board. (Do
not mistake the wire colors for power and
ground. They are not.)
The cable is about twice the length you need
for the standard installation. Some alternate
solder points are provided if you want to be
creative. You don't have to shorten the wires
but it is recommended that you cut the length
down by half then strip and tin the leads.
PCB shown reverse angle.
CE20* :
The RED wire should be soldered onto IC22 pin 3.
A15 :
The WHITE wire should be soldered onto IC23 pin 4.
[Alternate A15 points:
IC63 pin 4 -or- IC34 pin 5.]
A14 :
The BLACK wire should be soldered onto IC23 pin 5.
[Alternate A14 points:
IC63 pin 3 -or- IC34 pin4.]
