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Converting Cromemco IMD disks to a flat file question

RichCini

RichCini

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Location
Long Island, NY
All --

I'm attempting to use a Cromemco emulator (https://www.sydneysmith.com/wordpress/run-cdos/) as part of some work I'm doing with the 86-DOS project. The emulator seems to use only flat/binary files and I can't seem to get the ImageDisk incantation right to convert available CDOS disk images from IMD to flat -- the images available are generally CDOS DSDD 8" format in which Track 0 is 26x128 and the remaining are 16x512. I've also tried HxC to convert them, but no dice. Does anyone have a method/way to convert these that I can try?

Thanks!
Rich
 
Yes, with and without the /E parameter. The file size that is produced (1182720) does not match the size of the flat file provided by the emulator (1256704) which is (1*26*128)+(153*16*512). I did message the author of the emulator to see if he's done this conversion before or it's quite possible that the images available on Bitsavers and elsewhere have a slightly different format.
 
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AFAIK, the image produced by IMDU is in sector-number order. Did you manually examine the image on bitsavers using the IMDV utility? Could it be that the emulator expects the images in all one side, the all the second side order rather than the side-to-side order that IMD uses? Do you have any single-sided IMDs to play with?
 
No, I didn't examine it yet. Let me do that. Looks like Track 0 is also MFM 512 bytes rather than FM 128 bytes and the chromix header starts at sector 2.

I grabbed a copy of SBASIC from bitsavers and converted it -- regular SSSD 26x128 -- and it works just fine in the emulator with using nothing other than the "/b" parameter. Bitsavers doesn't appear to have a DSDD image to try.

The DSDD images I'm trying are from https://deramp.com/downloads/mfe_archive/010-S100 Computers and Boards/00-Cromemco/40-Cromemco Software/ASMB Assembler/
 
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Will do. I just grabbed a version of CDOS 2.58 from Dave Dunfield's site, converted it, and it ran just fine. It must be an issue with the way those disks had been converted. That disk is the same format as what the emulator author used -- CP/M FM track 0, MFM for the rest.
 
Unfortunately I don't have my imaging setup setup so I can't test it. What I can say from using IMDV on those images is that its a straight 16*512*154 images without the FM Track 0. I'm going to look for other copies of the assembler and see. I'm using this for the Seattle Computer 86-DOS reconstruction work we're doing.
 
I downloaded "run-cdos0258-2.zip" and extracted the files. The drivea.dsk file appears to be
a RAW image (Sector Dump).

Code: 
Track 0 is 26x128 and the remaining are 16 x 512

Track 0 26 x 128 = 3328 = 0xD00

Track 1 16 x 512 = 8192 = 0x2000
153 Tracks = 8192 * 153 = 1253376
153 Tracks + boot track's 3328 = 1253376 + 3328 = 1256704

Directory is at Track 2 = 0x2D00 = 11520 Decimal = 3328 + 8192 = 11520 = 0x2D00
00002D00   81 43 44 4F  53 30 32 35  38 00 00 00  10 80 00 40  .CDOS0258......@
00002D10   00 00 01 00  02 00 03 00  00 00 00 00  00 00 00 00  ................
00002D20   00 43 44 4F  53 20 20 20  20 43 4F 4D  00 00 00 6F  .CDOS    COM...o
00002D30   04 00 05 00  06 00 07 00  08 00 09 00  0A 00 00 00  ................
00002D40   00 49 4E 49  54 32 37 31  20 43 4F 4D  00 00 00 58  .INIT271 COM...X
00002D50   0B 00 0C 00  0D 00 0E 00  0F 00 10 00  00 00 00 00  ................
00002D60   00 58 46 45  52 20 20 20  20 43 4F 4D  00 00 00 3B  .XFER    COM...;
00002D70   11 00 12 00  13 00 14 00  00 00 00 00  00 00 00 00  ................
00002D80   00 43 44 4F  53 47 45 4E  20 43 4F 4D  00 00 00 80  .CDOSGEN COM....
00002D90   15 00 16 00  17 00 18 00  19 00 1A 00  1B 00 1C 00  ................
00002DA0   00 43 44 4F  53 47 45 4E  20 43 4F 4D  01 00 00 80  .CDOSGEN COM....
00002DB0   1D 00 1E 00  1F 00 20 00  21 00 22 00  23 00 24 00  ...... .!.".#.$.
00002DC0   00 43 44 4F  53 47 45 4E  20 43 4F 4D  02 00 00 04  .CDOSGEN COM....
00002DD0   25 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00  %...............
00002DE0   00 57 52 54  53 59 53 20  20 43 4F 4D  00 00 00 09  .WRTSYS  COM....
00002DF0   26 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00  &...............
00002E00   00 53 54 41  54 20 20 20  20 43 4F 4D  00 00 00 48  .STAT    COM...H
00002E10   27 00 28 00  29 00 2A 00  2B 00 00 00  00 00 00 00  '.(.).*.+.......
00002E20   00 45 44 49  54 20 20 20  20 43 4F 4D  00 00 00 38  .EDIT    COM...8
00002E30   2C 00 2D 00  2E 00 2F 00  00 00 00 00  00 00 00 00  ,.-.../.........
00002E40   00 44 55 4D  50 20 20 20  20 43 4F 4D  00 00 00 1C  .DUMP    COM....
00002E50   30 00 31 00  00 00 00 00  00 00 00 00  00 00 00 00  0.1.............


1256704 Jul  8  2018 drivea.dsk


# cpmtools
# CRO5  Cromemco CDOS - DSDD 8" - 512 x 16
diskdef cro5
  seclen 512
  tracks 154
  sectrk 16
  blocksize 2048
  maxdir 256
  skew 11
  offset 11520
  boottrk 0
  os 2.2
end


$ cpmls -f cro5 -D drivea.dsk
     Name    Bytes   Recs  Attr     update             create
------------ ------ ------ ---- -----------------  -----------------
CDOS    .COM    14K    111    
CDOSGEN .COM    34K    260    
DEBUG   .COM    10K     78    
DISKCOPY.COM    12K     86    
DUMP    .COM     4K     28    
EDIT    .COM     8K     56    
INIT    .COM    12K     94    
INIT271 .COM    12K     88    
MEMTST8 .COM     4K     26    
SCREEN  .COM    12K     87    
STAT    .COM    10K     72    
WRTSYS  .COM     2K      9    
XFER    .COM     8K     59    
   13 Files occupying    142K,    1082K Free.


Larry
 
Thanks Larry. The author said to me that his emulator supports only the 4FDC, so I suspect the images I happen to be trying to use from Deramp may be for the 16FDC? Not 100% sure yet, but the author is checking it out to see.

Rich
 
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