Yamaha TG500 Owner's Manual page 98

PERFORMANCE EDIT MODE / 3: Full Edit. 3-1: Layer
EF Param (Effect parameter)
86 3-2-11: CONTROL 1 / 3-2-12: CONTROL 2
MIDI CONTROL CHANGE NUMBER/DEVICE
Range: Depends on selected effects.
Selects the effect parameter to be controlled by the specified MIDI device.
"Ef1Prm1" through "Ef1Prm8" on the display stand for "effect 1 parameter 1"
through "effect 1 parameter 8". Likewise "Ef2Prm1" through "Ef2Prm8" on the
display stand for "effect 2 parameter 1" through "effect 2 parameter 8". The
parameters available for each effect are different, but the name of the selected
parameter will be shown between the parentheses on the top line of the display.
Parameters that can not be assigned to the sliders are indicated by dashes
("--------") instead of a parameter name. In addition to the indivual effect
parameters a range of send level, balance, and LFO parameters are also avail-
able, as listed below: