FPGA: What We Bought and Why
My dad and others are investigating FPGA as the basis of custom
processor work. LaFarr would like to build a processor capable of
arbitrary length numbers. I would like to build an FPGA Mippy
variant. My dad would like to build a babbage machine.
So we all have our desires.
In common, we'd like to find one FPGA vendor that offers:
- A large enough FPGA for us to do our work; we don't know if
that's 10K gates or 50K gates, but it's more than 1K.
- One that supports memory; either SRAM or DRAM (or SDRAM or DDR
DRAM, etc.). Basically, something with a built in memory
controller.
- Ideally, the board would have RAM on-board; or have a DIM slot for RAM.
- Some devices built in would be useful; USB, EtherNet, Parallel, Serial IO, etc.
We've issued a purchase!
On Tuesday, November 24th, 2003, I issued a purchase for 3
B5-X-Super-Value-Packs , 3
Power supplies,
and 3
mounting boards.
Getting Started Links
This is a NEW section for my dad, LaFarr and I. Hopefully we'll learn
more about FPGA's through these links:
Useful Links
Some of these links are links-to-links, others (I'm interested in)
have been explicitly duplicated here:
Why
Here are the links and notes that got us to the above purchase decision:
- Rabbit
Semiconductor makes a board not with FPGA but with a dedicated Zilog
Z80-like processor. This is a nice board in that it has all the built
in pieces parts we'd want, but instead of giving us an FPGA, it has a
built in processor. Ideally, we'd find a version of the Rabbit board
with a built in FPGA. Maybe we'd make one by adding our own FPGA in
their proto-typing area.
- Some guy (?) has investigated this
board. He seems really happy with it. At US$442, the B5-X-Super-Value-Pack
comes with a 256KB of
SRAM, 32MB of
Compact Flash (slow, but very useful), and some I/O. This seems
like the most reasonable contendor I've seen yet.
- EasyFPGA has two boards.
One hosts the
Xilinx Spartan-II FPGA (Xilinx has moved on to the Spartan 3, and
only the Spartan IIE is hi-lighted on their web site), the other board
hosts the Altera
ACEX FPGA.
- Altera has a list of
development kits.
- Colorado Electronic Product
Design has a couple of boards. The CXS200 also uses the
Xilinx Spartan II . They also have the CAS10 Statrix board
whish uses the Altera
Stratix FPGA. Niether board has any SRAM.
- Parallax (remember the
Basic Stamp?) has
some FPGA based boards. These boards don't have SRAM built in,
either.
- El Camino GmbH (of Germany) has some boards . The Digilab CC
board (EUR$700) comes with an Altera Cyclone FPGA and 1MB of memory
(256K x 36bit of SRAM).
- XESS.com makes a few boards
that are architecturally more interesting. They have more I/O, more
RAM controllers, everything is on the same board (no wires), etc.
It's a very clean system, but it's $900. There is one $150 board that has good
features.
I would think that SRAM, or compact flash would be very useful.
After all, I'm trying to build a micro-processor. And, LaFarr is
trying to build a math-engine. Either way, RAM is really helpful.
So, hmm. It looks to me like the B5-X is still the best.