[sebhc] Re-creating actual floppies from archive

Dwight Elvey dwight.elvey at amd.com
Wed Mar 15 11:43:40 CST 2006

>From: "Dave Dunfield" <dave06a at dunfield.com>
>> Hi Joe
>>  .h8d are a hard sectored images. Use my utility
>> in the utilities directory. You need to actually
>> write the disk on a H89 with a hard sectored controller.
>> You'll need a PC that boots to real DOS, serial cable
>> and the H89 must have a serial board with the LP: port.
>> You also need a hard sectored disk.
>>  I just described this to someone else a few messages back.
>> Using H89LDR9.ZIP.
>>  Dave's site has some tools to handle emulation on the
>> a PC and I think he has a way to transform h8d files
>> to his format used by his emulator.
>>  I doubt that PIE for hard sector HDOS would run under CP/M.
>> Dwight
>Ok - now I understand whats going on - the original message was
>posted in response to directions on how to find ImageDisk on my
>site, which caused me to think it was related to ImageDisk (or at
>least something from my site).

Hi Dave
 I was getting confused as well.
>Unless someone has abused the extension for other purposes,
>.H8D is just a raw image of the binary content of the hard-sectored
>disks. It does not contain the headers, and the data is in 1:1 (ie:
>non interleaved) ordering.
>I "invented" the .H8D extension name (not the file format) when I
>created my H8 simulator - it goes along with .H8T which is a H8
>Tape Image File. The format of the .H8D file is described in the
>help for the simulator.

 It is a good name. Originally, I create raw images with
the .img name but I think others saw that in conflict with your
tool. You'd already had the H8D format for your simulator
so it was a natural selection to match.

>If I ever get a physical H17, I would write a little program that could
>be booted as a tape image to read/write the disk images - Perhaps
>Dwights program does this?

 It doesn't load from tape. You need to enter 50 bytes to get
the bootstrap started. Once started, one can create a non-hdos
disk that will boot so that you don't need to reenter the 50
bytes( recommended but not required ). 
 The only thing is that it was not written for a soft sectored
controller and uses some vectors into the H17 ROM that are not
standard HDOS disk functions. It could be rewritten to handle
soft sectored if I had a soft sectored controller for either the
H8 or the H89. So far I've not seen one. Of course, someone
else could write the soft sectored operations and use my tool
to bootstrap. As long as the code uses the same sequences
that I use to load and upload images, it can be transferred.
You need to be able to initialize, format, read and write sectors.

>For soft-sectored disks, you should be able to use my ImageDisk
>program. If you have a raw-binary image, you can use the supplied
>BIN2IMD utility to add format information (which you will have to
>know and specify), and then the main IMD program to write the
>image to a physical floppy disk.

 They just need to have a 360K drive on the PC with your tool :)

>dave06a (at)    Dave Dunfield
>dunfield (dot)  Firmware development services & tools: www.dunfield.com
>com             Collector of vintage computing equipment:
>                http://www.parse.com/~ddunfield/museum/index.html
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