[Coco] 6809 computer boards (was French Translation Compensation)

jdaggett at gate.net jdaggett at gate.net
Wed Nov 21 00:01:46 EST 2007

On 20 Nov 2007 at 17:08, Joel Ewy wrote:

> Frank Swygert wrote:
> > There are plans for a 6809/6845 based computer here:
> > http://www.dunfield.com/products/projects.htm. I read about it --
> > uses a 14.xx Mhz crystal for everything and runs around 7 Mhz (uses
> > overclocked 68B09E).  Not sure if the floppy controller chip used is
> > available any more though.
> >
> > There don't seem to be any US manufacturers using a 6809 for
> > anything now. The 68HCxx controllers pretty much took over whatever
> > market there was for the 6809. Maybe NitrOS-9 should be ported to
> > something like a 68HC11, which might be usable in a CoCo3 like
> > system...
> >
> Of course, now we can do 6x09 in FPGA...  Who needs dedicated silicon?


Right now NOS of dedicated silicon is still slightly cheaper than FPGA. John Kent's CPU09 
core does fit into a XC2S200 chip with about 65% of the device utilized. This is optimized 
for speed. One could the sacrifice some speed for a smaller area. Also going above about 
300K gate equivalent devices are all in BGA packages. That is without a doubt not 
solderable for most hobbyists. Cost is about $35 for 208 pin QFP in single unit with 
configuration prom.

The Spartan 2 line of Xilinx chips are the only one that will tolerate interfacing with 5 volt 
logic. The Spartan 2e and Spartan3 series will not tolerate 5 volt logic levels. Not certain 
about Altera, Lattice or Actel. 


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