Nintendo GAME BOY Programming Manual page 86

Game Boy Programming Manual
Name Address Bit 7
NR32 FF1C
Output Level:
00: Mute
01: Output waveform RAM data (4-bit length) unmodified.
10: Output waveform RAM data (4-bit length) shifted 1 bit to the right (1/2).
11: Output waveform RAM data (4-bit length) shifted 2 bits to the right (1/4).
Name Address Bit 7
NR33 FF1D
Name Address Bit 7
NR34 FF1E
Counter/Continous Selection
0: Outputs continuous sound regardless of length data in register NR31.
1: Outputs sound for the duration specified by the length data in register NR31.
When sound output is finished, bit 2 of register NR52, the Sound 3 ON flag,
is reset.
Initialization Flag
When the Sound OFF flag (bit 7, NR30) is set to 1, setting this bit to 1 restarts
Sound 3.
6 5 4 3 2 1
6 5 4 3 2 1
6 5 4 3 2 1
0
R/W(Only the shaded portion
( ) can be read.)
Output Level Selection
0
W
Low-Order Frequency Data
0
R/W(Only the shaded portion
( ) can be read.)
Output Level Selection
Counter/Continuous Selection
Initialization Flag
86