semi-homemade micro - test-drb@ccmp.vtda.org

13 Nov 2005

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Subject: Re: semi-homemade micro
   From: "Chuck Guzis" <cclist at sydex.com>
   Date: Sun, 13 Nov 2005 17:33:32 -0800
     To: cctalk at classiccmp.org

On 11/13/2005 at 5:19 PM woodelf wrote:

 >Want to try an emulation project?  take a 8048
or 49, strap EA 
>(uses external rom then) and write a program to make port 0 and 
>some latches and stuff on the bus port look like a version of
>your favorite CPU of any word length.  Sure it will be slow 
>(8049 @11mhz run instructions at 1.3us) but different! hang 
>ram rom and IO even front pannel on the emulation and you have
>anything you can imagine and fit in 4k or eprom and 128bytes 
>of internal ram (8049).  
Why not something like an Atmel ATMega?  Fast and cheap. 
That would work too.  I picked 8049 or 8051 series as they are also 
cheap often found in useless  equipment and tools to work with them 
are free and I have a coffee can full of them. ;)

At the other extreme a PIC might do a it too. The idea remains
no differnt than using a PC to emulate Xyz save for a smaller 
machine IE: a chip maybe slower and embeddable.  The side benefit is
the "microcode" can have a debugger built in.

Allison