Yamaha RS7000 Owner's Manual page 277

Plug in the flat cable backward.
4.
Disconnect the flat cable.
•
Insert the opposite plug into the connector.
•
The connector has a cut-out that prevents it from being connected in an incorrect orientation.
Connect the flat cable.
5.
Connect the flat cable from the I/O expansion board (the thin, flat cable) to the corresponding connector on the RS7000's circuit
•
board (marked "C" in the illustration below: CN16).
The connector is "keyed" so that it will only go in one way.
C
6. Insert the AIEB2 I/O expansion board.
Support the I/O expansion board as shown in the illustration below, and fasten it to the rear panel by screwing in the three screws
•
(B) that you removed at Step 3 above.
CN 16
I/O cover
1. Installing Optional Equipment
(B)
(B)
RS7000 277