[Coco] 6821 and 6551 compatible parts @ 14Mhz Bus Speed

[Stephen H. Fischer]

Hi,

Rockwell was not the origin of 6521 and other chips in the 65xx series.

Synertek right here in Sunnyvale, CA created them and I have the original 
data sheets, data books and so on.

Not to mention a large number of Synertek 65xx chips in KIM's, SYM's and 
home built boards.

I even have SN 00001 of the conversion kit for the SYM-1 to allow use of the 
6809 CPU instead of it's normal 6502.

I ran FLEX 6809 on my SYM-1, perhaps the only person in the world to do so.

Stephen H. Fischer


----- Original Message ----- 
From: <coco at yourdvd.net>
To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
Sent: Sunday, April 29, 2007 9:28 AM
Subject: Re: [Coco] 6821 and 6551 compatible parts @ 14Mhz Bus Speed


> Yes, the 6521 PIA is pin compatible with the 6821, their 6545 is pin
> compatible with the 6845, etc. Rockwell originally made the 65xx
> series, but I suppose WDC (not the one that makes hard drives, but
> Western Design Center) has kept them alive and IMPROVED. -robert