Motor Control - Nintendo GAME BOY Programming Manual

Game Boy Programming Manual
!
Upper ROM Bank Register (ROMB1)
Specifies the higher-order 1 bit of a 9-bit ROM bank.
The ROM bank can be changed by writing the desired ROM bank number to the ROMB1
register (any single address in 3000h-3FFFh).
! RAM Bank Register (RAMB)
Specifies the RAM bank.
The RAM bank can be changed by writing the desired RAM bank number to the RAMB
register (any single address in 4000h-5FFFh).
Bits 0-1: Register for RAM bank setting
Bit 3: Motor control register (1: motor ON; 0: motor OFF)
Note: Be sure to set the bits marked with
The default values are set automatically when power is turned on.

5.5 Motor Control

5.5.1 Vibration Level
Control of the rumble motor consists of setting it to ON or OFF.
The vibration level can be controlled by sending pulses of combined ON/OFF instructions in short
cycles. Please comply with the following points when implementing vibration control.
(1) Set the frame rate to 1 frame per 1/60 second and control vibration frame by frame.
(2) At the start of vibration control, send a startup pulse (at least 2 ON frames).
A startup pulse also should be sent if the width of an OFF pulse is 3 or more consecutive
frames. This is necessary because startup from a complete stop requires a certain
amount of time. (see Ex. 5)
to 0 before using them.
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