Progress Documentation

                                         for

                        ADFS 2.50 (82C710 based floppy drivers)

This document records all significant events, bugs, comments etc. during the development of the ADFS 2.50 floppy drivers:

1. 28 Nov 1990 - Design phase begins
2. 10 Dec 1990 - Coding begins on ADFS17
3. 29 Jan 1991 - First version to provide basic operation:

           a) Read/write sectors
           b) Background operations
           c) Mount automatically determines ANY! density and sector size
           d) State driven motor controller and disk control system
           e) Disk Control Block based queued operations
   

   The following deficiencies are known:

           a) No support for disk change
           b) Min/Max sector number fudged for mount
           c) Seek and Restore DiscOps not supported
           d) Format not supported
           e) MultiFS format not supported
           f) Double step and sequenced head options not handled
              correctly for mount after format
           g) Logical to physical drive mapping is required to
              support non sequential drive numbers
           h) Drive detection after reset
           i) Implement escape and timeout inhibit
           j) Implement read track DisCOp as read track of ID's
           k) Error number mapping
           l) Retry algorithm
   

   4) 31 Jan 91 - Old style format support, error number mapping

   5) 6 Feb 91 Disk change support

   6) 11 Feb 91
   

           a) Mount now reads whole track of sector ID's to identify sectors
              per track and min/max sector numbers.
           b) ReadTrack, Seek and Restore DiscOps added.
           c) Escape and timeout options.
   

   7) 18 Feb 91 - First complete working version

        The following enhancements will be made:
           a) New FIQ routines to improve data transfer rate with scatter lists
           b) 177X MultiFS format track support
           c) Test for 40 track drives in FlpInit
           d) Lock/Unlock drive to use DCB's
        The following anomalies remain:
           a) A restore may be needed after each change of drive, need 2 drives to check this
           b) During "*BACKUP" the scatter lists sometimes appear to have no end!
           c) Jonathan's "Tester" program sometimes bombs with "insufficient stack for
              trap handler".
       
   

   8) 21 Feb 91 - Problems with scatter lists fixed, works with RiscOs 2.08

        The following enhancements remain to be made:
           a) New FIQ routines to improve data transfer rate with scatter lists
           b) 177X MultiFS format track support
           c) Test for 40 track drives in FlpInit
        RiscOs 2.08 format action does not check for disk in correctly!
        When running under V2.08 sometimes get error with directory '@' not found
   

   9) 1 Mar 91 - New FIQ routines introduced.

   10) 8 Mar 91 - Merged with CP's IDE drivers, all working