No it wasn’t. It’s true that the Utility disk does need to have the 
write-protect tab set to work properly. But my copies of the disk didn’t start 
working properly until I figured out the sector IDs and how to write them to 
the copy of the disk.

 

Kurt

 

From: M100 [mailto:m100-boun...@lists.bitchin100.com] On Behalf Of Brian White
Sent: Sunday, August 27, 2017 9:14 AM
To: m...@bitchin100.com
Subject: Re: [M100] Utility disk image from sector access

 

It wasn't this simple?

 

On Aug 23, 2017 8:16 PM, "Brian White" <bw.al...@gmail.com 
<mailto:bw.al...@gmail.com> > wrote:

Did you open the write-protect tab on the disk?

 

I have observed that it ignores an officially copied disk (made on a 720K disk 
using the backup utility), if the write-protect hole is closed.

 

On Aug 23, 2017 4:05 PM, "Kurt McCullum" <kurt.mccul...@att.net 
<mailto:kurt.mccul...@att.net> > wrote:

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 
<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. 

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