[Coco] mess HD problem

Bill Nobel b_nobel at hotmail.com
Wed Aug 6 23:48:58 EDT 2014


Yeah thats why I am confused as well.  I do know Alan’s code as we have worked together, what he did in mess is what I don’t know.  There must be something in RBF that makes the difference.  I need to check that, but I think that be why.

Bill Nobel

> On Aug 6, 2014, at 8:58 PM, Bob Devries <devries.bob at gmail.com> wrote:
> 
> Hi Bill,
> 
> If the hpa setting isn't used, then I'm at a loss to explain why "correcting" that setting in my DD descriptor has made the problem go away.
> 
> Regards, Bob Devries
> Dalby, QLD, Australia
> 
> On 7/08/2014 12:22 PM, Bill Nobel wrote:
>> Yep I thought so emudsk itself doesn’t touch hpa from the descriptor at all, it’s hard coded for $FF8x,  so that won’t make a difference for Bob’s problem, unless he isn’t using emudsk.
>> 
>> Bill Nobel
>> 
>>> On Aug 6, 2014, at 7:00 PM, Bill Nobel <b_nobel at hotmail.com> wrote:
>>> 
>>> Hmm, Robert your post pointed out something I have wrong in my /DD descriptor.  Mine is currently set to $FFE0 and I’m using EmuDsk.  I do only use one vhd and everything works good.  I now need to look at the source now to see if hpa is even used.
>>> 
>>> Bill Nobel
>>> 
>>>> On Aug 6, 2014, at 5:09 PM, Robert Gault <robert.gault at att.net> wrote:
>>>> 
>>>> Bob Devries wrote:
>>>>> Hi all,
>>>>> 
>>>>> well, changing the port address to $FF80 appears to have fixed the problem.
>>>>> 
>>>>> I don't know how I came by a module with the incorrect hpa. Could it be that a
>>>>> previous version of emudsk used that address?
>>>>> 
>>>>> Thanks for your input everyone.
>>>>> 
>>>>> Regards, Bob Devries
>>>>> Dalby, QLD, Australia
>>>>> 
>>>> Bob,
>>>> 
>>>> Here is some info.
>>>> 
>>>> *Technical specs on Virtual Hard Disk interface Alan DeKok: JVC, MESS and VCC
>>>> 
>>>> *	Address       Description
>>>> *	-------       -----------
>>>> *	FF80          Logical record number (high byte)
>>>> *	FF81          Logical record number (middle byte)
>>>> *	FF82          Logical record number (low byte)
>>>> *	FF83          Command/status register
>>>> *	FF84          Buffer address (high byte)
>>>> *	FF85          Buffer address (low byte)
>>>> *       FF86          DR# 0=first drive 1=second drive; MESS only
>>>> 
>>>> Look at MESS/SRC/machine/coco_vhd.c
>>>> 
>>>> -----------------------------------------------------------------------------
>>>> *	The JV Coco3x has 2 .vhd drives with the second address set as:
>>>> *	Address       Description
>>>> *	-------       -----------
>>>> *	FFE0          Logical record number (high byte)
>>>> *	FFE1          Logical record number (middle byte)
>>>> *	FFE2          Logical record number (low byte)
>>>> *	FFE3          Command/status register
>>>> *	FFE4          Buffer address (high byte)
>>>> *	FFE5          Buffer address (low byte)
>>>> 
>>>> 
>>>> -- 
>>>> Coco mailing list
>>>> Coco at maltedmedia.com
>>>> http://five.pairlist.net/mailman/listinfo/coco
>>>> 
>> 
> 
> 
> -- 
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco



More information about the Coco mailing list