[Coco] Can't copy real floppy to CoCo-SDC on a CoCo 2

[K. Pruitt]

----- Original Message ----- 
From: "Darren A" <mechacoco at gmail.com>
To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
Sent: Saturday, February 28, 2015 7:51 AM
Subject: Re: [Coco] Can't copy real floppy to CoCo-SDC on a CoCo 2


> On Sat, Feb 28, 2015 at 3:51 AM, wrote:
>
>> Thanks, Darren. I connected a different CoCo 2 this morning and got the
>> same results. So that removed the CoCo 2 as being anything unique. The 
>> only
>> remaining variable became the MPI. I have been using an UNMODIFIED MPI
>> (26-3124).
>>
>> I replaced the MPI with a PAL UPGRADED MPI (26-3024) and I can
>> successfully use "BACKUP 0 TO 1" between a real floppy and an SD card 
>> image.
>>
>> So apparently, this problem is only arising when using an UNMODIFIED MPI.
>> This should shed some light on what may be happening in the code when
>> running the "BACKUP" command.
>>
>
>
> I just tried using an unmodified 26-3124 MPI with a 16K CoCo 2 and a 64K
> CoCo 2. There were no problems using BACKUP 0 TO 1 to copy from an FD-501
> floppy (slot 4) to the SD card (slot 1).
>
> You have identified your MPI as being the problem, but I don't think it's
> the UNMODIFIED status at issue. There is something else wonky about that
> MPI but it's not clear to me what it could be.
>
> - Darren
>
> -- 

I have an unmodified 26-3124 and an unmodified 26-3024.

The SDC seems to work perfectly under Basic with the 3124, but hangs when 
trying to boot NitrOS9 and stock OS9.

However, I didn't try the backup thing that Mike is having problems with as 
I don't have a physical drive 1 any longer.  But I did backup a disk from 
the SDC to a physical drive 0 and then back again. without issue using a 
3024 MPI.

The unmodified 26-3024 works perfectly with the SDC and allows full 
functionality under Basic, NitrOS9 and stock OS9.

So yeah, definitely something is up with the 3124.  But I also thought it 
was due to not having the MPI upgraded, but now that we see the problem with 
the 3124 and a Coco 2 that kind of rules it out.

The 3124 is simply wonky.