Creating And Transferring Score Data; Transferring Score Data; Summary Of Bgm Flags - Nintendo GAME BOY Programming Manual

Game Boy Programming Manual

3. CREATING AND TRANSFERRING SCORE DATA

3.1 Transferring Score Data

BGM can be played with the APU by using the SOU_TRN command to transfer original score data to
the prescribed area of APU RAM. The user area is the 8 Kbytes from 2B00h to 4AFFh.

3.2 Summary of BGM Flags

Code
00h Dummy flag for retriggering
10h
Fh
80h BGM stop flag
FEh Use prohibited (used by system)
FFh Use prohibited (used by system)
Note: If 01h-0Fh are set without score data being transferred, the BGM built
into the system is played.
This BGM is exclusively for use by the system, so 01h-0Fh should not be
written as a BGM flag without original score data being transferred.
Even if original score data is transferred, there is risk that the sound
program will run uncontrolled if a non-designated code is written.
Muting is in effect when the system is initialized, so the BGM playback
settings must be made after muting is canceled.
SOUND Command
04h d7-d0 [bit]
Flag Description
190