Yamaha Portable Grand DGX-670 Owner's Manual page 14

Before connecting the instrument to other electronic
components, turn off the power of all the components.
Also, before turning any components on or off, make
sure to set all volume levels to minimum (0). Otherwise,
damage to the components, electrical shock, or even
permanent hearing loss may occur.
Assigning a function to each pedal
Various functions can be assigned to each pedal
connected to the [AUX PEDAL] jack or the [PEDAL
UNIT] jack „ including start/stop of Song playback
and controlling Super Articulation Voices.
These can be set on the Pedal tab of the Controller
display called up via the [MENU] button (page 100).