[Coco] Re: CoCo gcc project

[Theodore A. Evans]

On 11/02/03, jdaggett at gate.net wrote:

> My thoughts on CORDIC approach is to do the algorithms in FPGA 
> and stick the chip off as a coprosessor. One can tap off the 28MHz 
> clock of the Gimme chip and buffer it to provide the clock to the 
> FPGA. Inside a Spartan II/IIe part you can then double that 
> frequency and run the coprocessor at 56MHz. If it takes the Cordic 
> processor 21 cycles to generate the sine of an angle, that will be 
> about 375 nS. 
> 
> There are a few cordic cores for FPGA that are open and free to 
> use on the internet. Just need to write and add more functions.

If you are going to go to all that trouble, it is probably easier,
cheaper, and faster to use a dedicated math coprocessor like the
m68881 or m68882 instead.

-- 
Always yield to temptation, it may never return.
Theodore (Alex) Evans            | alxevans at concentric.net
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