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MYIDE.ASM
This page contains links to software that interfaces with the IDE drive/CF card S100 Bus board. The board itself is described here.
 
MYIDE Menu
 
The above menu is that of the most recent version (V3.1) of this software and can be downloaded from the bottom of this page.

The CPM Program MYIDE.ASM now has a fairly long history. It was originally written for the V1 version of the IDE/CF card board with only one IDE slot back in 2009. It was modified for the two slot version of the board later.   

HISTORY
In all cases the program assumes a sector size as 512 bytes/sector.  The original software assumed a CPM3 "disk" format of  61 (3DH) sectors/track with each sector on a track starting 0,1,2, 3 etc.  This format was chosen for a Seagate 6531 IDE drive (a once common HD at the time). The Seagate 6531 had 62 sectors/track, one sector was used as a spare for R/W sector errors -- thus I used a 61 sectors/track format.  With CF cards I retained this CPM3 format and have used it ever since.  This avoids having different CPM disks/CF cards with different/incompatible CPM.SYS files on them. 

In retrospect the choice of 61 sectors/track was a less than optimum choice for CF cards.  This is due to the fact that IDE disk hardware utilized the LBA mode of sector addressing rather than the raw CP/M track and sector values. Sectors are simply numbered 0,1,2,3... FFFFFFH, no heads tracks etc. are involved. So sectors go 0..3DH then
100H...13DH,  then 200H...23DH etc.  Clearly the wasted space ("holes") is not an issue. The maximum capacity of a disk for CPM3 was 8MB, most CF cards are in the GB range.

However if does create a problem when trying to build a CP/M disk image by disk sector map editing software.  It is quite difficult to calculate where to locate data on the disk.  Worse, common software like CPMTOOLS will not work.    The solution was made by David Fry was to make some changes to the ‘wrlba’ code sequences in the CP/M bios files to calculate the true LBA address (without holes) from the track and sector requests,  then we can predictably locate data into the correct disk sector locations and ensure compatibility with the CPMTOOLS toolset.  Please see David's write-up board build info CPM installation info and the corresponding .zip files for more information.

Jay Jaege corrected and enlarged upon the original MYIDE.ASM version yielding a V3.0 version that allows the user to work with the "Holes" or "No Holes" CPM disk Formats. 
The only thing the user has to be careful with is to not mix disk formats.  Here is the signon menu of that version.
        
  MYIDER V3.0 Menu
    
Before Dave Fry's and Jay Jaege's modifications  I incorporated  some elements of MYIDE into the Z80 Master Monitor, the 8086 Monitor and 80386 monitor as well as the FPGA Z80 and FPGA 80286 monitors.  One day I hope to double back and make these IDE modules more generalized. However they all work fine for testing the IDE/CF card board and CPUs for individual sector read/writes etc. as they are.

At the start or 2021 I started writing a version for the 68000 and 68030 CPU Boards to incorporate into their onboard ROM monitors.  This time I tackled the Sectors/track issue by making it completely flexible.  Since we are now dealing CF Cards in LBA mode we can have any number of CPM sectors/track we like.  The IDE program now has a menu option (M) to set this value dynamically.  There is a slight speed advantage in having 0FFH sectors/track.  Normally the user would choose between options:-
 
1.    0....3DH sectors/track.    This is the original "with holes" disk format.  The CPM.SYS file works on my system with all 'old' disks
2.    0....3FH sectors/track      This is the "no holes" format.  This format allows for easy use of CPMTools and other CPM disk image software.
3.    0....FFH sectors/track      This is also a "no holes" format.  It makes a CPM BIOS easier to write and operate. It will not work with most "real" Hard Disks
4.    0....XXH sectors/track      This format could be used for a specific "real" Hard Disk with predefined sectors/track.

While I was at it I made other improvements to the MYIDE menu.  The Menu letters and options arrangement are now a little better arranged. As far as possible the letter corresponds with the command.

There was one other correction/change.  Sectors on a track can be accessed with a numbering scheme of 0,1,2,3... or 1,2,3 4.... The former is usually used for CF cards,  the latter for "real" Hard Disks.  In writing a CPM3 BIOS you can have either option.  The Digital Research CPM3 SKEW Macro defines which. See here.

All of this is now incorporated in the V3.1 version of MYIDE.ASM.  This is the version I recommend for most users. 
You can download the  MYIDE.COM file to a CPM disk from your PC with PCGET.COM

Software Downloads
Old version of  MYIDE.ASM  (V2.91)           (12/23/2017)
Old version of MYIDE.ZIP  (V2.91)           
 (12/23/2017)
 
A 4K ROM based version of MYIDE.ASM can be see here and downloaded here. (3/15/2011)
 
A major updated version of the diagnostic program MYIDE.ASM written by Jay Jaeger can be downloaded from here:-
MYIDE.ZIP  (V3.00)                                (5/31,2019)
MYIDE.ASM (V3.00)                            
  (5/31/2019)

Most Current MYIDE.ZIP   (V3.11)
    
 (2/20/2019)
Most Current MYIDE.ASM  (V3.1)            
 (2/20,2019)

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This page was last modified on 03/05/2021