Worth Data P11/12 - Manual (Page 59)

L-2
Before inserting the new EPROM, notice that the EPROM has a small groove in
one end; the end with the groove in it must match the groove in the socket which
it is to be inserted into. Don't insert the chip backwards -- line up the groove in
the chip to be on the same side as the socket's groove.
You may need to slightly bend into the center the legs of the EPROM so that they
can be inserted into the socket. Place the chip into the socket and begin to lightly
push the chip into the socket. Unless you check, you may bend one of the leads
not in a hole underneath the chip -- making your Reader disfunctional. Once you
are sure all legs are positioned into the holes correctly, you can push hard until the
chip is firmly positioned into the socket.
After turning the re-powering the WDP by plugging back in the "Y-Cable", you
should hear 3 beeps. This indicates that the EPROM has been successfully
installed. If it doesn't beep three times, immediately unplug the "Y-Cable" and
remove the EPROM and check for bent legs. Also be certain you have not placed
it in upside down, (not matching the notches). If you have placed it upside down
and were a little slow in removing power, you probably have burnt out the EPROM
and will have to replace it before proceeding.