Re: CBM-900 floppy disk format/encoding

From: Uffe Jakobsen <uffe_at_uffe.org>
Date: Sat, 29 Oct 2011 02:20:24 +0200
Message-ID: <4EAB46C8.9040909@uffe.org>
On 2011-10-29 01:37, Hoffmann-Vetter, Martin wrote:
>
>> Just besides an EPROM labeled "Z8000 Fl. Cont. S41 6-20-85"....
>
> Can you dump the rom?

That is the plan for next week - along with all the other roms

>
>> The EPROM, MOS 6508, MOS 8723 and some other nearby discrete
>> components on the mainboard seems to constitute a separate floppy
>> controller just as the external CBM drives are made.
>
> That's very interesting. So this was a modern SFD1001 without the ieee
> interface? Did anyone know more about the floppy controller chip MOS 8723?
>

PS: The CBM-900 actually does have an external GPIB/IEEE-488 interface 
on its back side.

>
> What's the history from this C900? Is it a workstation or server model?
>

The short story is that it was never returned to Commodore for 
destruction upon request and hence survived at a local Danish 
consulting/engineering company.

It appears to be a server model.
Besides the GPIB/IEEE-488 the mainboard has two RS-232C's and one 
centronics parallel port on the back of the system.

The "mezzanine" graphics card is marked "Z8000 LR DISPLAY BOARD" LR for 
Low Resolution and has a VDC 6845 chip on board and two additional 
RS-232C's.

/Uffe



       Message was sent through the cbm-hackers mailing list
Received on 2011-10-29 01:00:03

Archive generated by hypermail 2.2.0.