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Apple II file corruption?

Posted: Fri Dec 30, 2011 1:22 am
by Cliff
Having received a Kryoflux from Santa I was eager to check out my (very, very, very) old Apple II disks. I set up with a Samsung SFD-560D drive and all seemed to be well. I used the Windows graphical UI set to "Apple DOS 3.3+ sector image" to read the disks. The first couple of disks I attempted contained several bad sectors but four or five others read all 35 tracks without complaining about any errors. I duly attempted to load the images into the WinApple emulator and all the disk images listed the files on them when entering "CATALOG". The strange thing is that every single BASIC program on every single disk seem corrupted. They load okay, but when you attempt to list them the line numbers are jumbled and most listings end with a line number 255 being displayed repeatedly, but amidst this there are elements of the correct program being shown.

I know that at least some of the files are okay as I managed to test them on a real Apple II less than a year ago. Can anyone shed any light onto why this might be happening? Could the floppy disk drive that I'm using be at fault? Do I need to set some parameters? Should I be using the command line tool for more control over the imagine process?

I seem to be so close to seeing those programs I wrote as a ten year old so many years ago. So close and yet so far....

Re: Apple II file corruption?

Posted: Fri Dec 30, 2011 1:39 am
by TeaRex
Use DTC's image type 8a "DSK, DOS 3.3 interleave", not 8 "Apple DOS 3.3+ sector image", for all 5.25" Apple II images. By established convention, almost all Apple II emulators expect "DOS order" images, which is what image type 8a produces; they can't deal correctly with the type 8 "sector header order" images.

Re: Apple II file corruption?

Posted: Fri Dec 30, 2011 1:51 am
by Cliff
You, sir, have made my day! That worked straight away. It's amazing that these disks still work after over 30 years! Kryoflux is a truly amazing piece of kit. Looks like tomorrow is going to be spent going through a myriad of Apple II and BBC Micro floppy disks. Happy days :)