VDK format

[admin]

Hi there!

I'm a long time enthusiast of old computers and I own a Dragon 64 with a disk drive.

I've tried succesfully to write disk images to disks and run them in the actual machines. Now I'm trying the same with dragon disks. The question is that there are many programs that can write a number of exotic formats to disk, but none appear to read the .VDK files.

Are there any specs of the format or any windows tool that can format/write dragon disks?

Regards!

[admin]

The only "Microsoft" tool that will read/write VDK is a tool called VCOPY.EXE (attached to this post)... However, this will only work under MS-DOS/Win98 and not Win 2K, XP or Vista due to the way it talks directly to the disk controller. Phil has some instructions for doing this under Linux which he posted to the old forum - I will see if I can dig them out and re-publish.

I use an MS-DOS boot disk/USB key with the VCOPY.EXE file + any files I want to write......

To write a Dragon image you must "format" the disk on the Dragon first (INIT) and then write the image to it.

VDK is a very simple format that only stores the content of a disk, not its structure but it was the 1st format adopted by the Dragon emulators - current emulators will work with DMK files.

[admin]

Thanks for the tip!

I managed to run Vcopy but I don't have my Dragon at hand to format the disks, so it won't write them...

There is a tool for formatting 3.5" and 5.25" disks for Amstrad CPC use called CPCDiskXP, which relies on a special driver by Simon Owen (FDInstall) for low-level acces to the disk controller(obviously Windows cannot read disks formatted that way but hey, you got your disc ready for use).

I don't know if the program is open source but it would be a nice thing to have a program like that for Dragon disks.

By the way, I think that it would be nice to have a code section in the wiki so that people can submit code that can be helpful to others. I wrote a C++ class for reading and saving .VDK files, that it's quite simple, but I had a hard time looking at emulators code just to figure out how it worked.

[admin]

Attached is an attempt by the VCOPY author of a program to INIT dragon disks on a PC... .Never tried it myself and it isn't widely available... Let me know if it works...

[admin]

Thanks for the tip!
There is a tool for formatting 3.5" and 5.25" disks for Amstrad CPC use called CPCDiskXP, which relies on a special driver by Simon Owen (FDInstall) for low-level acces to the disk controller(obviously Windows cannot read disks formatted that way but hey, you got your disc ready for use).

I don't know if the program is open source but it would be a nice thing to have a program like that for Dragon disks.

Well, the programming interface is available on the fdrawcmd site, as I used it to write an interface unit for Delphi, which I have used to write utilities to exchange files with Spectrum +3/Amstrad disks, and another with Acorn BBC DFS disks. A Dragon VDK reading/writing utility should be fairly easily doable.

By the way, I think that it would be nice to have a code section in the wiki so that people can submit code that can be helpful to others. I wrote a C++ class for reading and saving .VDK files, that it's quite simple, but I had a hard time looking at emulators code just to figure out how it worked.

Seconded, or to provide Dragon/CoCo code that others might find usefull.

Cheers.

Phill.

[admin]

Attached is an attempt by the VCOPY author of a program to INIT dragon disks on a PC... .Never tried it myself and it isn't widely available... Let me know if it works...

Hi! Just tried it and works pretty well. Now vcopy does write the image to the disk. I'll try the disk as soon as I can to confirm it really works on a real machine.

Thank you!

I'll take a look at the driver documentation and I'll try to init a disk using the driver.

[admin]

I have the source code for VCOPY if thats any use - its (c) Stuart Orchard but if it would help to develop a better utility...

[admin]

It may be very useful, because I'll need to know the actual sector and track layout. In any case both of you we'll be credited for your help.

Is there any manual on how is the data layout on the disk? I remember the Amstrad CPC has the disk structure in the user manual, but I don't if the dragon user's manual contains such information.

Thank you very much for your help!

[admin]

I remember the Amstrad CPC has the disk structure in the user manual, but I don't if the dragon user's manual contains such information.

Unfortunately, it does not : all the Dragon Data manuals were pretty "basic", to say the least.
There might have been more advanced information published in some other books, but I just don't know. I can't remember ever reading any such information in "Inside The Dragon", though I may check...

[sixxie]

Graham Kinns' info files to the rescue once more!

http://www.grempc.demon.co.uk/dragon/info/drgndos.html

Must remember to archive these some day just in case... It's (mostly) all stuff that's written down in other places (in this case, I'm pretty sure I learnt the DragonDOS directory structure from an issue of Dragon User), but nicely collated