A |
4.Alternate tracks per volume is taken from the attach packets alternate cylinders to reserve field (byte offset $1F for "old" attach ($08), or offset $29 for "new" ATTACH ($78)) multiplied by the number of heads (to convert to tracks).
5.The number of sectors per track, logical sectors per track, the attach packet (byte offset $0C) plus spare sectors per zone (byte offset $1E) if zone = track bit 11 byte offset $10 = 1
6.Bytes per sector is taken from the attach packet byte offset $1C.
7.Interleave is taken from the format packet byte offset $0E.
8.Track skew factor field is left as the default value as returned from the mode sense command.
9.Cylinder skew factor field is left as the default value as returned from the mode sense command.
10.Drive type field bits HSEC bit are set if the
11.This field is left as the default value as returned from the mode sense command.
Before formatting a Winchester disk, the MVME147 SCSI firmware sends a mode select command for drive geometry parameters (page 4) to the controller. Below is the command descriptor block for the mode select command:
Mode Select Command CDB
| BYTE OFFSET | VALUE | COMMENTS | |
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0 | 15 | Command code | ||
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1 | 10 | LUN = 0, PF = 1, SP = 0 | ||
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2 | 00 | Reserved | ||
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3 | 00 | Reserved | ||
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4 | (Note) | Parameter list length | ||
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5 | 00 | Control byte: no link, no flag | ||
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