Classicamiga Forum Retro Edition
Thread: Program to Chop files (880kb) to fit in a 720Kb dd disk
Tiago 13:45 16th August 2007
Dont know if anyone post anything about it, but here it goes:

If you need to pass a file from PC -> Amiga (if you want to convert ADF to real amiga disk) you can do this:

After you format a PC disk to 720kb you need to put the ADF (or other file) in it, but the adf is 880kb, so you may need to chop the file in smaller parts.

There is a program (15kb) called chooper (easy to find) that can chop the file.

Example:

In PC type:
CHOPPER S=#64 MYGAME.ADF MYGAME

it will chop the file in multiple 64kb files.

In Amiga type:
CHOPPER +J MYGAME MYGAME.ADF


In PC works nice, and i am sure that in amiga with Crossdos will work also.

There is also the Chopper file for the Amiga. Dont know if the Pc file will run in normal crossdos emulation. But there is a the Amiga file.
[Reply]
Harrison 14:16 16th August 2007
Using a file splitting tool is definitely a good method to get larger files over to the Amiga using 720K PC floppy disks..

An alternative method that will work well for most ADFs is to ZIP the ADF which will normally get it down below the 720K size needed and then using TransADF to transfer it back to disk on the Amiga as that can use the files while still zipped so no need to decompress them on the Amiga first.

http://aminet.net/search?query=TransADF
[Reply]
Tiago 14:23 16th August 2007
Originally Posted by Harrison:
Using a file splitting tool is definitely a good method to get larger files over to the Amiga using 720K PC floppy disks..

An alternative method that will work well for most ADFs is to ZIP the ADF which will normally get it down below the 720K size needed and then using TransADF to transfer it back to disk on the Amiga as that can use the files while still zipped so no need to decompress them on the Amiga first.

http://aminet.net/search?query=TransADF

hummm, that sounds good.
But, TransADF will recognize the zip made under Windows?

so transadf is like a Unzip+adf2disk mix?
[Reply]
Harrison 14:50 16th August 2007
Originally Posted by :
But, TransADF will recognize the zip made under Windows?
No, sorry. I should have mentioned that. ZLib (which TransADF uses) supports PKZip and GZip. These two compression formats are more widely used across all platforms that Zip but use the same compression routines due to ZLib being written by the same developer as Zip.

When you see an ADF file with the file extension ADZ it has normally been compressed using GZip. But on the PC you can rename these files to .zip and WinZIP will open and allow you to extract the contents. You just cannot write to GZIP files using WinUAE.

To create the gzipped files on the PC use the free utility IZArc found here. IZArc can also handle LHA and many other formats so is very useful.

Originally Posted by :
so transadf is like a Unzip+adf2disk mix?
Yes, TransADF is a bit like adf2disk or transdisk, with the ZLib library support built in for the compression. It also allows you to make Zipped ADFs straight from disk on the Amiga or to write zipped ADFs directly back to disk. There is also a GUI frontend available to make it easier to use.

The big advantage of creating zipped ADFs directly on the Amiga is that they often offer even better compression than DMS, and are easier to work with.
[Reply]
Tiago 15:20 16th August 2007
Sounds good, i will do it.
Thanks Harrison
[Reply]
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