Figured it out. There is indeed an ID field for every track. This is read by backup.ba before the track data is read. Then on the write portion of backup.ba, it is written back to the track before the data is laid down. The end result is a perfect copy that boots just as the original Utility disk.
Kurt From: M100 [mailto:m100-boun...@lists.bitchin100.com] On Behalf Of Kurt McCullum Sent: Wednesday, August 23, 2017 1:06 PM To: m...@bitchin100.com Subject: Re: [M100] Utility disk image from sector access A bit too soon to declare total success. I can duplicate data disks without any issues. I can even duplicate the Utility disk. But even though the duplicate has all the same data, it won’t auto boot. So those extra save commands that I think play with the ID portion of the track are essential to creating a true duplicate of the Utility disk. I’ll get there but it’s going to take a bit to figure out the ID information. Kurt From: M100 [mailto:m100-boun...@lists.bitchin100.com] On Behalf Of Kurt McCullum Sent: Wednesday, August 23, 2017 10:13 AM To: m...@bitchin100.com <mailto:m...@bitchin100.com> Subject: Re: [M100] Utility disk image from sector access I’ll document what I’ve got John. The backup utility that uses floppy does some strange calls which I don’t understand at all. But, if one reads the tracks from 0 to 80 and then in turn writes them from 0 to 80, those calls are not needed. Backup does some extra reads to determine just how many sectors to copy instead of reading the entire disk. And there are some writes that I don’t understand at all. I suspect they have something to do with the ID of the sector but I’m not sure. Without a manual I’m just guessing. My utility is a simple brute force read of every track and then the same routine in reverse. Slow, but it works. Kurt From: M100 [mailto:m100-boun...@lists.bitchin100.com] On Behalf Of John R. Hogerhuis Sent: Wednesday, August 23, 2017 9:36 AM To: m...@bitchin100.com <mailto:m...@bitchin100.com> Subject: Re: [M100] Utility disk image from sector access On Wed, Aug 23, 2017 at 9:24 AM Kurt McCullum <kurt.mccul...@att.net <mailto:kurt.mccul...@att.net> > wrote: Success! I’ve got my utility reading AND writing TPDD2 disk images with the sector access commands. I’ve got a bit of cleanup and testing left to do and then I’ll put it in the members area. Kurt Documentation on the sector access protocol would be good too :-) It's the one dark corner of tpdd2 protocol (that we know of). -- John.
