Crane Snack Eenter I, Troubleshooting & Repair Manual

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Snack - Based Troubleshooting and Repair Guide
1670065 Page 2 of 54 September, 2002
2. EPROM Replacement
CAUTION:
Do not remove the new EPROM from its shipping carton until you are ready to
use it.
CAUTION:
Observe Electrostatic Discharge precautions to protect the electronics from
damage while they are being handled. Wear a grounded wrist strap connected to
any unpainted metal part of the machine. If a wrist strap is not available,
remove any electrostatic charge (static electricity) from yourself by touching any
unpainted metal part of the machine before handling any electronic component.
Do this often during the removal and installation process.
1. See the shaded area representing EPROM U4(figure 1). These devices have various means
of showing how they are to be oriented on the circuit board. Some EPROMs will have a
small notch which matches the notch printed on the controller board. Other EPROMs may
have a small dimple as shown, others may have a painted stripe. Take note of where the
locating mark is on the EPROM currently mounted on the controller board. Your new
EPROM will be placed in that same orientation. Some EPROMs have 28 pins, (opposed to
32 pins on newer snack-based models), so they will not use the entire socket (Newer snack-
based machine’s EPROMS will cover entire socket). The shaded area on the figure is where
the new EPROM will go, leaving the four holes at the bottom of the socket empty if you are
using older EPROM.
2. Carefully remove the old EPROM from the controller board. Use an EPROM removal tool
or a thin tool such as a small screwdriver or knife blade to gently rock the EPROM from its
socket.
3. Carefully insert the new EPROM in the controller board. MAKE SURE THE LOCATING
MARK (NOTCH, DIMPLE, STRIPE) ON THE EPROM IS FACING THE SAME WAY AS
ON THE OLD EPROM! Make sure each of the pins is in its respective hole in the socket
before pushing the EPROM into place.
4. Carefully seat the EPROM into place using uniform pressure all around.