Re: Simple Forth processor witten in VHDL.
A couple of items regarding this project. I have been programming in Forth
for over ten years now. It is used in all of our robot products. The
educational line of robots that include Whiskers, uses a 68HC11 with Forth
on it. This machine is programmable by the user. Forth is essential for
this product. We also make military robots that are really embedded systems
where the user does not need to program the robot at all. These systems use
the 68HC11 with Forth currently. I envision being able to replace the
68HC11 and Forth with an ASIC/FPGA VHDL solution down the road. I looked
around for someone who might have implemented a Forth Processor and really
only found one person in China and he didn't finish it. It was based on the
MISC type architecture. So I said to myself, I guess I will work one and
see if there is any interest out there to help if it is public domain
design.
My personal reasons are:
1) Learn how to build systems in VHDL.
2) Build a Forth Processor for people to use in their designs.
3) It will be fun and educational, everyone who participates will learn
some interesting stuff about Forth Processors, VHDL and FPGA's.
4) I also am very curious about the gates count/FPGA cost to implement
the design.
I talked to Quicklogic, if we supply them the VHDL code and an order for 100
chips, it would cost only $16 if the code would fit on their 12,000 gate 84
pin PLCC device. A 25,000 144 pin device would be about $31 dollars.
A 200 mhz Forth Processor with custom I/O ports for these prices would
interest me, anyway.
Don Golding
