Yuzo Koshiro (NES Driver)

Yuzo Koshiro

Released 1987-07-17 Programmers Yuzo Koshiro Language 6502 Assembly

Yuzo Koshiro is the unofficial name of the NES sound driver used by Yuzo Koshiro in Aspect's only NES game, Legacy of the Wizard (NES). It is assumed Koshiro programmed the driver for a few reasons:

1.) He was the audio role credited in the game.
2.) Koshiro is known to program his own sound drivers on every game console he worked on.
3.) The driver used in Legacy of the Wizard doesn't seem to match with any other NES sound drivers.

Release History

The driver was only used in one game, Legacy of the Wizard (NES). The game was released in both North America and Japan, but never saw a release in Europe.

Output

Yuzo Koshiro's NES sound driver outputs to the RP2A03 and, like most NES sound drivers, doesn't use the DPCM channel.

Games

Released	Title	Sample
1987-07-17	Legacy of the Wizard (NES)

Technical

Frequency Registers

Koshiro's driver, along with several other NES sound drivers, use a special algorithm. Only the first/lowest octave is coded, and then the driver is programmed to divide each note of the lowest octave by 2 to achieve higher octaves. For example, C-1 is 6AE in hexidecimal, and 6AE % 2 = 357, which is what note C-2 is. It is assumed this algorithm proceeds until B-7.

B-7 = 0E
A#7 = 0F
A-7 = 0F
G#7 = 10
G-7 = 11
F#7 = 12
F-7 = 14
E-7 = 15
D#7 = 16
D-7 = 17
C#7 = 19
C-7 = 1A
B-6 = 1C
A#6 = 1E
A-6 = 1F
G#6 = 21
G-6 = 23
F#6 = 25
F-6 = 28
E-6 = 2A
D#6 = 2C
D-6 = 2F
C#6 = 32
C-6 = 35
B-5 = 38
A#5 = 3C
A-5 = 3F
G#5 = 43
G-5 = 47
F#5 = 4B
F-5 = 50
E-5 = 54
D#5 = 59
D-5 = 5F
C#5 = 64
C-5 = 6A
B-4 = 71
A#4 = 78
A-4 = 7F
G#4 = 86
G-4 = 8E
F#4 = 97
F-4 = A0
E-4 = A9
D#4 = B3
D-4 = BE
C#4 = C9
C-4 = D5
B-3 = E2
A#3 = F0
A-3 = FE
G#3 = 10D
G-3 = 11D
F#3 = 12E
F-3 = 140
E-3 = 153
D#3 = 167
D-3 = 17D
C#3 = 193
C-3 = 1AB
B-2 = 1C5
A#2 = 1E0
A-2 = 1FC
G#2 = 21A
G-2 = 23A
F#2 = 25C
F-2 = 280
E-2 = 2A6
D#2 = 2CF
D-2 = 2FA
C#2 = 327
C-2 = 357
B-1 = 38A
A#1 = 3C0
A-1 = 3F9
G#1 = 435
G-1 = 475
F#1 = 4B9
F-1 = 501
E-1 = 54D
D#1 = 59E
D-1 = 5F4
C#1 = 64E
C-1 = 6AE

Addresses

Legacy of the Wizard (U): $1FDC1-$1FDDA
Legacy of the Wizard (J): $1FDD0-$1FED9