[Coco] Re: Converter update

jdaggett at gate.net jdaggett at gate.net
Fri Apr 8 10:44:24 EDT 2005


Torsten 

The advantage that a microcontroller will have over a PLD is if one wants a 
software solution over a hardware solution.The Xilinx  9500XL series of CPLDs are 
3.3 volt with 5 Volt tolerance devices. They operate at speeds up to about 175MHz 
and 36 macrocell devices are  generally in the $1 to $2 range. Software to design 
and  program them is free. It is quite easy to make a JTAG interface cable or buy 
one for under $30. 

Also if one is willing to extend the learning curve, the hardware solution can be 
simulated before committing to programming and testing. A 36 macrocell PLD will 
be equivalent to about 800 logic "and" gates. 


Basically it all depends on which the designer is most familiar with. In something as 
simple as this interface is,  either approach is adequate.

james

On 8 Apr 2005 at 8:58, Torsten Dittel wrote:

To:             	coco at maltedmedia.com
From:           	Torsten Dittel <Torsten at Dittel.info>
Date sent:      	Fri, 08 Apr 2005 08:58:47 +0200
Subject:        	[Coco] Re: Converter update
Send reply to:  	CoCoList for Color Computer Enthusiasts 
<coco at maltedmedia.com>
	<mailto:coco-
request at maltedmedia.com?subject=unsubscribe>
	<mailto:coco-
request at maltedmedia.com?subject=subscribe>

> > Any particular reason for choosing a programmable logic chip over a
> > low-end microcontroller? A microcontroller would give more
> > flexibility and be much easier to code for.
> 
> I agree an MC would speed things up and make it more flexible for
> future adaptions. I'm sure there are cheap solutions out there which
> are EEPROMable via a serial port like the 6811 has been. Maybe the
> CoCo should better "talk serial" to the MC and the MC doing all the
> communication with the AL chips with its IC2 bus.
> 
> Torsten
> 
> 
> -- 
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco





More information about the Coco mailing list