Structure of the W30 disk - Rev 1 - Jan 95
1) Tone Directory : Location : Side 1 Track 7 Sector 9
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16 bytes per tone :
Offset Size Field Remarks
0 8 Name
8 1 Output # Often 0
9 1 sub-tone # indicates the parent subtone number
10 1 sub-tone flag 1 if tone is subtone, otherwize 0
11 1 rate flag 1 if rate=15K zero if rate=30K
12 1 org key Key where sample is recorded (midi number?)
13 1 ram number 0 if RAM A, 1 if RAM B, 2 if unused
14 1 Data position Used to determine where the sample data is
15 1 Data size Number of 0.4 sec blocs the data is made of
2) Sample Data location :
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The location of the first tracks containing the sample data can be
computed using the following formula :
Track=8+2*(Data Position)+36*(RAM number)
Side=0
Sector=0
And is in the following order :
Track i+1
Side 0
Sector 1,2,...9
Side 1
Sector 1,2,...9
Traack i+1
Side 0
.. and so on
It is stored in chunks of 0.4 sec. meaning that each size units is made
of 2 tracks.
2 tracks= 2*2*9*512 bytes=18342 bytes.
Since the samples are 12bits, you store only 2 samples into 3 bytes.
The storing is made like this
Take 3 consecutive bytes and split them into 4 bit parts
Byte 1 Byte 2 Byte 3
H1/L1 H2/L2 H3/L3
The two samples values are H1/L1/H2 and H3/L3/L2
from each unit you should extract 18342/1.5 = 12288 samples.
3) Tone Parameters : Location : Side 1 Track 7 Sector 1->8
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128 bytes per tone... should be pretty much like the S-550
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