Showing changes from revision #2 to #3:
Added | Removed | Changed
Offset | Meaning |
---|---|
+0 | Sector size |
+4 | Gap 1 side 0 |
+8 | Gap 1 side 1 |
+C | Gap 3 |
+10 | Sectors per track |
+11 | |
+12 | Options |
+13 | Start sector on a track |
+14 | Sector interleave |
+15 | Side/side sector skew (signed) |
+16 | Track/track sector skew (signed) |
+17 | Sector fill value |
+18 | Number of tracks to format (ie cylinders/drive: usually 80) |
+1C-23 | Reserved, must be 0 |
+24 | Sector ID buffer (1 word/sector) |
# | Meaning |
---|---|
0 | Hard disc |
1 | Single density (125 Kbps FM) |
2 | Double density (250 kbps FM) |
3 | Double density (300 kbps FM), i.e. higher rotation speed DD |
4 | Quad density (500 kbps FM) |
8 | Octal density (1000 kbps FM) |
Bit | Meaning |
---|---|
0 | Index mark required |
1 | Double step |
2 – 3 | 0 = Interleaved side |
1 = Format side 1 only | |
2 = Format side 2 only | |
3 = Sequenced sides | |
4 – 7 | Reserved, must be zero |
Bit | Meaning |
---|---|
0 – 7 | Cylinder number mod 256 |
8 – 15 | Head (0 onwards) |
16 – 23 | Sector number |
24 – 31 | Log2(sector size)-7 |