Yamaha Mark IV Operating Manual page 11

Chapter 2: Basic Operations
5 Press (power button).
The Tablet Controller is turned on and the Play screen appears.
Function bar
Play screen
Note:
This may take approximately two minutes. When turning the Disklavier
back on after shutting down, be sure to wait 10 seconds before doing so.
Tip:
Pressing on the Media Center also turns the Disklavier on. In such
a case, be sure to press (power button) to turn on the Tablet Controller as
well.
Note:
After turning on the Tablet Controller for the first time, set up the Time
Zone. For the procedure, pg. 65 "Setting the Time Zone".
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