Re: [stella] FE, 3F, Bankswitching, and Data lines

Subject: Re: [stella] FE, 3F, Bankswitching, and Data lines
From: Adam Wozniak <adam@xxxxxxxxxxxxxxxx>
Date: Wed, 18 Dec 2002 09:18:32 -0800 (PST)
On Wed, 18 Dec 2002 mickey_m@xxxxxxxxx wrote:
> While I was making my cart, I put a frequency counter on A12 and got about a 
> 1Mhz for access.  I now this isnt the best way to do it, but it was enough for 
> me to realize that there was no way my microcontroller was going to be able to 
> make it.  Remember that some microcontrollers take multiple clock cycles per 
> instruction.  I was running at 20MHz but, at 4 cycles per instruction I was 
> really at 5MHz.  Thats at best 5 instructions per cart read!  Not enough time 
> for me.  I looked into CPLDs.

Ubicom (formerly Scenix) makes a 50MHz 8 bit micro (SX52BD) which 
does one instruction per cycle.

50/1.19 ~= 42 instructions per read.

Still a little tight for me.  I'm looking at CPLDs now.

Will code for food.


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