[Coco] mess HD problem

[Bob Devries]

Robert,
thanks for that information.

I looked at the drivers and descriptors in the current NitrOS9 
repository, and found that the emudsk there is built using $FF80 as the 
controller address.

I must somehow have mixed up the DD descriptor from an earlier/Alan 
Dekok version.

The CRC of the emudsk module matches that of the current NitrOS9 driver, 
so I assume I need to have $FF80 as the port address. I can't understand 
how it worked at all!

Thanks for your input.

Regards, Bob Devries
Dalby, QLD, Australia

On 7/08/2014 9:09 AM, Robert Gault 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)
>
>