Request info on editing disk image files.

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Terry Fox

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Feb 14, 2026, 10:01:18 PMFeb 14
to Altair 8800
 Can I ask how people add/change/delete the programs stored on disk image files?  Such as .dsk and .img, etc...
thank you
Terry

Walt Perko

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Feb 14, 2026, 10:11:20 PMFeb 14
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Hi, 

I mostly PCGET files from my PC via a RS-232 to USB cable and TeraTerm XMODEM ... 

I also PCPUT files so that I can have backups to upload to another computer.  


In this thread, a guy was working on a program:  "adgui.exe"  


I have the last version he posted, but I don't think it's done ... and it's been nearly a year since he posted anything new.  



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Patrick Linstruth

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Feb 14, 2026, 10:13:58 PMFeb 14
to Altair 8800
I use AltairZ80 or Altair8800 simulator to boot CP/M with the image and manage the files under CP/M. Standard CP/M “ERA” can be used to remove files. PIP can be used to copy files. The SIMH “R” and “W” programs are used to move files between the CP/M disk images and the host PC. Another nice thing about using the simulator is this works with any disk image supported by any of the supported disk controllers.

The following can be used with AltaIr8800 sim:

simh> ATTACH DSK0 CPMDISK.DSK
simh> ATTACH DSK1 ANOTHER.DSK
simh> BOOT DSK0

AltairZ80 simulator is a little more involved as you need to load the standard Disk Boot Loader in oder to boot standard Altair CP/M disks.

Altair8800 RW.jpeg

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Patrick Linstruth

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Feb 14, 2026, 10:19:35 PMFeb 14
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One of the problems with these stand-alone programs is they need to be configured for every disk image you’re working with. For example, Tarbell DD disks have the first track SD and the rest are DD. Some CP/M images use sector skewing. Sector size? Sectors per track?

This can be problematic with a separate program.

Using the simulator, you are using the same CP/M that you’d be running on the real hardware, so it’s already configured correctly. Just ERA, PIP, REN, R, W files as you normally would.

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WB4JFI

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Feb 14, 2026, 10:30:37 PMFeb 14
to Patrick Linstruth, Altair 8800
Thanks Patrick.
Yes, it would be great to use a CP/M emulator, but I don't know that the emulators can edit most of the various disk image files.  Can one emulator load & edit both .dsk and .img files for example?  How about other disk images?

I must admit that I'm forgetting more and more about this hobby every day.  Partly because I have too many projects going...
Terry

WB4JFI

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Feb 14, 2026, 10:35:33 PMFeb 14
to Walt Perko, Altair 8800
I would prefer to move more than one file at a time.  Yes, I'm lazy and get tired of manually typing all those file names.

That adgui.exe might fit the bill, if it comes out.
Terry

Patrick Linstruth

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Feb 14, 2026, 10:43:53 PMFeb 14
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I don’t know what an .img file is. If it is just raw sector data, that would be the same as the typical .dsk file. There are IMD files that some of the simulator devices support, though I prefer converting IMD to DSK, since nothing else (like PC2FLOP) support IMD.

AltairZ80, for example, supports the following disk controllers:

DSK (Altair)
DISK1A
DISK2
DISK3
IF3
CROMFDC
FIF
MDSK
MDSA
MDSAD
SCP300F
JADEDD
TARBELL
TDD
ICOM
DJ2D
DJHDC

If you have a CP/M image and the simulator has matching simulated hardware, it will more than likely run. If you email me a couple examples, I can see if they work.

With the exception of the JAIR, I don’t think any of the S100computers CF/SD CP/M images will currently work with the sim as they don’t provide any “standard” interface, though they could be made to.

Walt Perko

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Feb 14, 2026, 10:49:17 PMFeb 14
to Altair 8800
Hi, 

The last version he published is this:  https://www.brainless.org/Altair/Repository/adgui.exe

I've only used it to list the files in a .DSK so I can find a program ... then I mount the .DSK and PIP the file to a new .DSK 
 

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Walt Perko

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Feb 14, 2026, 10:50:26 PMFeb 14
to Altair 8800
Hi, 

Patrick, showing how to manipulate files in the AltairZ80Sim might make for a useful ZOOM demo video.  


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