RE: just dreaming.... 6525.... CPLD ... replacement for 6525

I have already coded up the VHDL for a 6525 TPI running in MODE 0 only for the CBM II 8088 coprocessor. I have synthesised it for a XILINX 
XC9572-7PC84 - but it could be synthesized for any other device if you have the necessary development tools. The CPLD I have used will 
need to be enhanced if interrupts are to be supported as I have 'maxed out' the macrocell usage of the XILINX device with just mode 0 
supported. I have tested the device in the simulator - but not in reality (I do not have a 6525 chip to compare my code to or any 
Commodore machine(s) to try it in).

If you would like a copy of my VHDL code - please send me a PM and I will be glad to forward you the files.

I would be more than happy to enhance the code to support the full functionality of the 6525 TPI device - but there are a few "grey areas" 
in the device documentation that I have uncovered that we will need to try and 'plug' to ensure 100% compatibility.

The biggest issue is the availability of 5V devices these days - as most manufacturers are moving to 3.3V or 1.8V devices. A small 
daughter card with the requisite voltage regulator and level shifting buffers should solve this problem though. Any PCB guys out there 
interested?

Dave


> Message Received: Jul 26 2012, 11:45 AM
> From: "didier derny" <didier@aida.org>
> To: cbm-hackers@musoftware.de
> Cc: 
> Subject: just dreaming.... 6525.... CPLD ... replacement for 6525
> 
> Hi
> 
> it's just a dream I had while I was reading the 6500 technical reference 
> manual.
> 
> recently you were looking for some 6525 to repair some equipement.
> apparently you never found the count of components you wanted ....
> 
> any hope to build  a replacement on a small board with a chip like 
> EPM7064SLC44-10N
> 
> I guess the 6525 is not too complicated .... ?
> the EPM7064SLC44-10N is 5V PLCC 44 not so expensive...
> 
> perhaps it could be used on a small board
> 
> something looking like a rom-el but to replace a 6525 ??
> 
> is it a problem of cost or an electrical problem ?
> 
> 
> --
> didier
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 

       Message was sent through the cbm-hackers mailing list