[Coco] V.PAGE 46551 and 46552 drivers

George Ramsower georgeramsower at gmail.com
Tue Jul 22 00:35:30 EDT 2008



> On Mon, 21 Jul 2008 15:46:42 -0600, George Ramsower 
> <georgeramsower at gmail.com> wrote:
>
>> ----- Original Message ----- From: "L. Curtis Boyle" 
>> <curtisboyle at sasktel.net>
>>
>>>>
>>>     That may be true for disk controllers, but RS-232 does allow 
>>> multiple cards (the Comm-4 board from Alpha technologies had 4 ports, 
>>> as an example). The device descriptor determines it by the address of 
>>> the card, and each get's their own buffer (especially if using SACIA 
>>> for 6551 based ports, and DACIA for 6552 based ports). When we used to 
>>> run the Coco 3/Nitros9 system here at work, we had 3 parallel ports, 
>>> and 8 serial ports (4 6551, 4 6552 (2 ports per chip on the latter), 
>>> and we drove 8 ADM terminals from those.
>>>
>>
>>  Are the drivers and descriptors available for these chips? I've been 
>> wanting to build a new board for my coco using one of these chips to 
>> replace the 6551 chips I'm using now.
>>  My current board has three of the 6551 chips and from what I hear, the 
>> 46551 and 46552 are superior.
>>  I use stock OS-9 L2 on a 512K CC3.
>>
>> Thanks,
>>
>> George
>
> Both SACIA and DACIA were part of Nitros9 at least up until 2.01, so I 
> assume the source should be with the current NitrOS9 project. Both were 
> originally done by Bruce Isted, and I don't recall too many changes being 
> done afterwards by any of us on the NitrOS9 team.
> Also, what I meant with "4 6551, 4 6552" is that we had 4 ports running 
> off of 6551 chips (4 chips; 1 port per chip), and 4 running off of 6552 
> chips (2 chips, 2 ports per chip, with up to 38.4kbaud and none of the 
> nasty bugs with date/DTR that the 6551's had). The 6552 was used in the 
> TC-9, and the Eliminator disk/hard drive/clock/parallel port/dual serial 
> port controller that Frank Hogg sold for the Coco. That was an excellent 
> controller, except for no RS-DOS compatibility, and it's use of obscure 
> (even at the time) WD-1002-05 controller cards (hope I got that last 
> number right; going from foggy memory here).
>
>
> -- 
> L. Curtis Boyle

 Thank you for being so kind with my stupidity. I was thinking of the chips 
from another mfg that works better. I think they have five digits in their 
nomenclature.

 I need to look into the 6552 and see if it is pin compatible.
 Perhaps I could just swap the chips if they are. .... assuming the drivers 
will work on those.
 Darn.. I still have about seven or eight of the 6551 chips left.

 The OS9 drivers work good up to about 9600 with the 6551 chips. Faster is 
always better!

George 




More information about the Coco mailing list