C# and Spartan 3 Starter Kit

Hello,

    I am a graduating college senior who is working on his seminar
project. I am trying to get a CM11a controller (x10 technology) to talk
to a Spartan 3 starter kit. I've written a programm in C# that allows
me to cut on a light via that controller. My goal is to download this
to the Spartan board, but instead of turning on a light, I would just
to display a simple statement through the board saying, "the signal
from the CM11a has been receive."  So my question is, is it possible to
run a program written in C#  on a Spartan 3 Starter Kit? If so what
will I need to use to run it.


             Thanks in advance,

                  Aaron

Aaron wrote:
> Hello,
> 
>     I am a graduating college senior who is working on his seminar
> project. I am trying to get a CM11a controller (x10 technology) to talk
> to a Spartan 3 starter kit. I've written a programm in C# that allows
> me to cut on a light via that controller. My goal is to download this
> to the Spartan board, but instead of turning on a light, I would just
> to display a simple statement through the board saying, "the signal
> from the CM11a has been receive."  So my question is, is it possible to
> run a program written in C#  on a Spartan 3 Starter Kit? If so what
> will I need to use to run it.
> 
> 
>              Thanks in advance,
> 
>                   Aaron
> 


Hmm......  Short answer no.   It sounds like you want to use an FPGA as 
a microcontroller.  This is normally done using the the Microblaze soft 
core (The Xilinx EDK).  The EDK toolchain (gcc based) allows you to code 
in C.  No one (at least that I know of) has a .net engine running on a 
soft CPU.  I am sure its possible by porting the work done on the Mono 
project but this would be a waste of time.  C# is more of a macro level 
(like VB) development tool.  I (at least in my opinion) don't feel that 
it is a serious tool for embedded programming.  Primarily because it was 
not designed to allow you have unprotected access to memory. No Dynamic 
Allocation, Garbage Collection etc!!!!.  It is critical in embedded 
systems to be able to talk directly to hardware registers, etc. C# 
simply can't do this (at least not in any way that is simple and easy.

  If you are still interested in just doing the work in C, get ahold of 
the EDK.  Its not that hard to get a simple system running using the 
base system builder.  Writing you own custom peripherals will take you 
alot longer if you dont know HDL.

I think you may be better off using a small 8-bit micocontroller (8051, 
PIC, etc).  You will actually get your project done in time.


-Eli

As a former senior design project lab instructor, let me give you a few
hints.

1) Make it simple. You don't have time to debug unnecessary crap. I've
seen great projects that would have earned A's had they been completed
- yet get C's because the students bit off more than they could chew,
and got stuck debugging unnecessary problems. This is an important
skill later, as well. Nobody wants to explain that a product will ship
late because some engineers "toy" broke something, and forced a long,
unnecessary, and expensive debugging cycle.

2) If you don't absolutely need it - don't worry about it. That's why I
asked if you really need configurable logic. FPGA's are neat, and in
some cases, invaluable - but if all you are doing is controlling a
serial device and an LCD - unnecessary. They add complexity, and design
time, without offering much in return. On the other hand, they do allow
you to do true system-on-a-chip designs. The S3 or S3E starter kits are
great for this, because they are entirely self-contained. I would
suggest you look at opencores.org. I am using the Plasma MIPS processor
in a design of my own, and you can cross-compile with either Windows or
*nix based compilers. If you have (or can get) the full Xilinx EDK,
Microblaze is a very nice soft processor, and you get a full
development environment.

Keep in mind, an FPGA will present an additional set of design problems
on top of all the others you have. Specifically, you must make sure
your design can make timing, your pin-out must match what is expected
by the rest of the system, and code debugging becomes more complex than
just "recompiling". You now have to generate a new bitstream, and
upload it to the target everytime you make a change. (EDK helps a lot
here)

3) C#, to my knowledge, is limited to a very few platforms, and as a
previous poster noted, none of them are microcontrollers. I'm not
anti-Microsoft, but .net was not intended for embedded computing. If
you can't use a PC (running Windows) as your controller, and must use a
micro, I would use C and/or assembly. It gets the job done, and you can
get free cross compilers to almost any platform known to man. Yes, you
can write C programs targetting Atari 400/800's and Commodore 64's if
that's your thing.

4) If you are planning to graduate this Spring, I would suggest hoofing
it. Debugging always takes an order of magnitude more than the initial
development - no matter how careful you were in the design phase.
Something about Murphy's law I think...

Finally, if you are set on using an FPGA, consider using finite state
machines (FSM) instead of a full processor. You would be amazed at how
much you can accomplish. I've done designs with reasonably complex user
interfaces with little more than an FSM and a ROM. Your application
practically screams for a well-designed FSM.

Remember, software is essentially a FSM executed on another FSM (the
CPU). Any software function, including recursion, can be fully
reproduced in hardware. The opposite is not true.