soft core micro controller as fpga IP

[Tan]

Hi,
Is it possible to design a micro controller design as fpga IP?
for ex.. i need to design intel 251 core with fpga...is it possible ?I have gone through many sites and could not find a perfect answer to this...Please help me out...

 

[Ice-Tea]

Do you mean off the shelf or do you want to do it yourself?

In addition to what big A and X have to offer, there are a number of softcores already developped: Linky.

 

[Tan]

I know Ice-Tea,If I want to develop it myself,what are the pros-cons?First of all is it possible to do it?
I found only one doc on this

.http://www.cast-inc.com/ip-cores/8051s/r80251xc/

The link you have sent contains the processors,I am talking about the controllers.

 

[joelby]

Pros: You can develop the architecture exactly how you want
Cons: You waste loads of time, when an existing core could have done everything for you

What do you think the distinction between a microprocessor and a microcontroller is? Traditionally, a processor was a chip that had few peripherals or memory built in and was pretty much useless on its own, while microcontrollers bundled RAM/ROM, timers, ADCs, GPIOs, special I/O peripherals and so on. In an FPGA it's reasonably straightforward to build a 'processor' as the core of your design, and then attach only the peripherals you need for a particular application.

Xilinx's EDK is a good example of this - the MicroBlaze processor has no I/O capabilities on its own, but you can attach GPIOs, memory controllers, Ethernet MACs, and so on using a standardised bus.

In general, you can reimplement any processor core on an FPGA. The challenges are that detailed design documents might not be publicly available, or the specifications can be incomplete or even contradictory. For 100% compatibility, you would need to write test programs that exercise ALL functions of the CPU in EVERY conceivable combination, and ensure that your own version replicates the physical device completely. As you might imagine, even with a moderately complicated CPU, this is nearly an impossible task to do unless you have (literally) thousands of years for all tests to run.

If the 80251 is broadly compatible with an 8051, your best bet would be to modify one of the open source or public domain 8051 cores.

 

[Tan]

Hi,
As you guys wrote a micro controller is a combination of micro processor,peripherals,gpio's.
So my question is anyways xilinx or altera or lattice are having soft ip processors in them.Can we use them to design 80251 micro controller?
if so how much time will that take to design and implement it?
first of all is it possible?did anyone did this?

awaiting your replies..

 

[aruipksni]

Hi,
As you guys wrote a micro controller is a combination of micro processor,peripherals,gpio's.
So my question is anyways xilinx or altera or lattice are having soft ip processors in them.Can we use them to design 80251 micro controller?
if so how much time will that take to design and implement it?
first of all is it possible?did anyone did this?

awaiting your replies..

if you really want to use 80251 - you can just buy the core from numerous suppliers.
if you want to do it by yourself as an exrcise - it depends how good you are.

 

[Tan]

if you really want to use 80251 - you can just buy the core from numerous suppliers.
if you want to do it by yourself as an exrcise - it depends how good you are.

Actually...Its not the point of buying it....We have done a project long back that contains 80251..and we want to try the same in FPGA domain...that is the reason for the above query asked......
I could not find enough documents on that..i wonder if anyone tried doing it and i certainly want to try it if it is possible with picoblaze...or the soft processor..

By the way I dint find any opensource code in opensource.org as well...please help me out

something like this....

http://www.cast-inc.com/company/blog/post.php?s=2011-06-20-chip-replacement-with-ip-and-fpgas-68000-processor-example

 

[joelby]

Hi,
As you guys wrote a micro controller is a combination of micro processor,peripherals,gpio's.
So my question is anyways xilinx or altera or lattice are having soft ip processors in them.

No FPGA 'contains' soft IP.. it's up to you to design anything and program it into the FPGA. You can run a soft IP processor in any FPGA (as long as the design fits).

Can we use them to design 80251 micro controller?

Yes! Subject to size constraints - it might not be possible on the absolute smallest FPGA device.

if so how much time will that take to design and implement it?
first of all is it possible?did anyone did this?

That'll be completely up to your design skills. Without very good documentation about the architecture, it will not be an easy task even for a skilled designer. As I said, without sufficient testing it might take a long time to find and fix all of the edge cases.