[Coco] mess HD problem

[Bill Nobel]

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)
> 
> 
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