[Coco] Another MESS Question

Robert Gault robert.gault at worldnet.att.net
Sun Dec 25 08:52:37 EST 2005


The image files will only grow if you write "passed the end" if the 
image. That means you need a version of format or DSKINI which actually 
writes to the image under the conditions of MESS.

Keeping OS-9 in mind as the prime OS, it is imperative that the .vhd 
image be formatted before anything is written to the disk. The catch21 
is that no physical formatting takes place, so nothing gets written past 
the end of the root directory. So, now what?!

There are three approaches for extending the .vhd to its full size 
before OS-9 use. 1) Use RGBDOS for the emulator and dskini any virtual 
Disk Basic drive. 2) Boot OS-9 from a floppy that has .vhd access, open 
/h0@, and write a byte at the end of LSN$59FFF. 3) Use a PC utility to 
populate the full $5A000 sectors with some character, ex. $E5.

Now the .vhd will be the correct size but filled with junk. If you like 
pristine disks and don't want to look at leftover PC files, you will 
need to write a short OS-9 program, probably in Basic09, to "wash" every 
sector passed the root directory.

Bob Devries wrote:
> more on that Virtual HD question... the VHD file is exactly 17291 
> sectors long on the PC hard drive. Even though the /H0 descriptor says 
> it is 90 MB, it isn't. Is it supposed to grow dynamically? If it is, it 
> isn't doing it.
> 
> Here's the ident of EMUDSK and H0:
> 
> Header for:  EmuDsk
> Module size: $00BC    #188
> Module CRC:  $85815B (Good)
> Hdr parity:  $66
> Exec. off:   $0021    #33
> Data Size:   $00FF    #255
> Edition:     $01      #1
> Ty/La At/Rv: $E1 $81
> Dev Dvr mod, 6809 obj, re-en, R/O
> 
> Header for:  H0
> Module size: $002F    #47
> Module CRC:  $BE79DA (Good)
> Hdr parity:  $CB
> Edition:     $52      #82
> Ty/La At/Rv: $F1 $81
> Dev Dsc mod, 6809 obj, re-en, R/O
> 
> -- 
> Regards, Bob Devries, Dalby, Queensland, Australia
> 
> Isaiah 50:4 The sovereign Lord has given me
> the capacity to be his spokesman,
> so that I know how to help the weary.
> 
> website: http://www.home.gil.com.au/~bdevasl
> my blog: http://bdevries.invigorated.org/
> 
> ----- Original Message ----- From: "Bob Devries" <bdevries at gil.com.au>
> To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
> Sent: Sunday, December 25, 2005 8:01 PM
> Subject: Re: [Coco] Another MESS Question
> 
> 
>> It seems that I'm not able to read past sector $438B (17291) using 
>> ded. If I try to, I get error 242, which is write protect.
>>
>> Any comments?
>> -- 
>> Regards, Bob Devries, Dalby, Queensland, Australia
>>
>> Isaiah 50:4 The sovereign Lord has given me
>> the capacity to be his spokesman,
>> so that I know how to help the weary.
>>
>> website: http://www.home.gil.com.au/~bdevasl
>> my blog: http://bdevries.invigorated.org/
>>
>> ----- Original Message ----- From: "Bob Devries" <bdevries at gil.com.au>
>> To: <coco at maltedmedia.com>
>> Sent: Saturday, December 24, 2005 4:49 PM
>> Subject: [Coco] Another MESS Question
>>
>>
>>> Is it possible to write protect the disks in MESS? If so, how is it 
>>> done?
>>>
>>> If not.... why am I getting error 242 when I try to copy files to the 
>>> virtual HD?
>>> -- 
>>> Regards, Bob Devries, Dalby, Queensland, Australia
>>>
>>> Isaiah 50:4 The sovereign Lord has given me
>>> the capacity to be his spokesman,
>>> so that I know how to help the weary.
>>>
>>> website: http://www.home.gil.com.au/~bdevasl
>>> my blog: http://bdevries.invigorated.org/
>>>
>>>
>>> -- 
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> http://five.pairlist.net/mailman/listinfo/coco
>>>
>>>
>>> -- 
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>>> Checked by AVG Free Edition.
>>> Version: 7.1.371 / Virus Database: 267.14.7/214 - Release Date: 
>>> 23/12/2005
>>>
>>>
>>
>>
>> -- 
>> Coco mailing list
>> Coco at maltedmedia.com
>> http://five.pairlist.net/mailman/listinfo/coco
>>
>>
>> -- 
>> No virus found in this incoming message.
>> Checked by AVG Free Edition.
>> Version: 7.1.371 / Virus Database: 267.14.7/214 - Release Date: 
>> 23/12/2005
>>
>>
> 
> 



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