Yamaha DX7 II FD Supplemental Booklet page 23

Accessing a Cartridge
Microtuning Scale
You may access a microtuning scale from a properly formatted
following the steps below.
Insert a cartridge formatted for Micro Tuning data into the cartridge slot. Then. ..
>Table select: for selecting a Micro Tuning,
including any of the 63 micro tunings in
the cartridge.
>A and >B: for setting which bank(s) the
selected micro tuning will affect.
>Key: a number of Micro Tunings will also
include this parameter to establish the
tonic key for the scale.
-19 -
RAM 4
cartridge by