Nintendo DMG-01 Manual - Page 49

FF23 NR 44

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Game BoyTM CPU Manual 2.13.1. I/O Registers Selection of the shift clock frequency of the polynomial counter: 0000: dividing ratio of frequencies * 1/2 0001: dividing ratio of frequencies * 1/2^2 0010: dividing ratio of frequencies * 1/2^3 0011: dividing ratio of frequencies * 1/2^4 : : : : : : 0101: dividing ratio of frequencies * 1/2^14 1110: prohibited code 1111: prohibited code 26. FF23 (NR 44) Name - NR 44 Contents - Sound Mode 4 register, counter/consecutive; inital (R/W) Only bit 6 can be read. Bit 7 - Initial (when set, sound restarts) Bit 6 - Counter/consecutive selection Counter/consecutive Selection 0 = Regardless of the length data in NR41 sound can be produced consecutively. 1 = Sound is generated during the time period set by the length data in NR41. After this period the sound 4 ON flag (bit 3 of NR52) is reset. by DP Page 49

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Game Boy
TM
CPU Manual
2.13.1. I/O Registers
Selection of the shift clock frequency of
the polynomial counter:
0000: dividing ratio of frequencies * 1/2
0001: dividing ratio of frequencies * 1/2^2
0010: dividing ratio of frequencies * 1/2^3
0011: dividing ratio of frequencies * 1/2^4
:
:
:
:
:
:
0101: dividing ratio of frequencies * 1/2^14
1110: prohibited code
1111: prohibited code
26.
FF23 (NR 44)
Name
- NR 44
Contents - Sound Mode 4 register,
counter/consecutive; inital (R/W)
Only bit 6 can be read.
Bit 7 - Initial (when set, sound restarts)
Bit 6 - Counter/consecutive selection
Counter/consecutive Selection
0 = Regardless of the length data in NR41
sound can be produced consecutively.
1 = Sound is generated during the time
period set by the length data in NR41.
After this period the sound 4 ON flag
(bit 3 of NR52) is reset.
by DP
Page 49