Hi, I hope this question is not too stupid. I'm aware of many free software (or rather free hardware) soft-cores for FPGAs on opencores.org and elsewhere, which is a great trend. However, is there also a free/open FPGA/CPLD design on which you can actually _use_ the free soft-cores? I'm not really an FPGA expert so maybe I'm missing something, but so far it looks like all the underlying FPGAs on which people use free soft-cores are highly proprietary and closed systems. That's at least true as far as the hardware is concerned (layout, schematics, chips, etc of which the FPGA consists, as well as JTAG and other programmers etc.), and very often also the software used for programming these things (often Windows-only, binary-only, proprietary software). Now, my questions is: does such a thing as a free (as in Free Hardware, i.e. VHDL/schematics/whatnot under an open license) together with free programming hardware and free programming software (and other tools) exist? Anybody working on such a thing? If not, what are the major obstacles? The ultimate goal would be to be able to build/design hardware solutions which are _really_ 100% Free/Open, even down to the FPGA layer itself. Thanks, Uwe. -- http://www.hermann-uwe.de | http://www.holsham-traders.de http://www.crazy-hacks.org | http://www.unmaintained-free-software.org

FPGA design software is an interesting thing, First up, to get the best of any FPGAs, the tools need to 'know' the chip , in detail, probably more detail than is open source / data book. Your talking NDA level. Second up, each chip family would need it's own optimiser. Now I say "gnu C, is a great free compiler", and I agree, but, there are a lot more different types of FPGA's that need 'special' bits than there are processors, QED: we'd need a lot more design effort than the gnu c guys have put in as we'd need more code. and unfortunately , we are primarily hardware guys, not C coders, so you might not find that many people to help. I seem to remember companies like ST once tried to support a GNU FPGA tool set, and if you do a grep around, you'll find a few tools on the web, But mainly for FPGA's , I'd suggest that people use one tool for simulation, and another tool to put code into FPGA. If your doing small designs, these tools are free form vendors, if your doing big designs, you are commercial, and you negotiate / pay for tools. andrewm at opencores.org -----Original Message----- From: cores-bounces at opencores.org [mailto:cores-bounces at opencores.org] On Behalf Of Uwe Hermann Sent: 26 February 2008 18:23 To: cores at opencores.org Subject: [oc] Free/Open FPGA/CPLD design? Hi, I hope this question is not too stupid. I'm aware of many free software (or rather free hardware) soft-cores for FPGAs on opencores.org and elsewhere, which is a great trend. However, is there also a free/open FPGA/CPLD design on which you can actually _use_ the free soft-cores? I'm not really an FPGA expert so maybe I'm missing something, but so far it looks like all the underlying FPGAs on which people use free soft-cores are highly proprietary and closed systems. That's at least true as far as the hardware is concerned (layout, schematics, chips, etc of which the FPGA consists, as well as JTAG and other programmers etc.), and very often also the software used for programming these things (often Windows-only, binary-only, proprietary software). Now, my questions is: does such a thing as a free (as in Free Hardware, i.e. VHDL/schematics/whatnot under an open license) together with free programming hardware and free programming software (and other tools) exist? Anybody working on such a thing? If not, what are the major obstacles? The ultimate goal would be to be able to build/design hardware solutions which are _really_ 100% Free/Open, even down to the FPGA layer itself. Thanks, Uwe. -- http://www.hermann-uwe.de | http://www.holsham-traders.de http://www.crazy-hacks.org | http://www.unmaintained-free-software.org _______________________________________________ http://www.opencores.org/mailman/listinfo/cores No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.21.1/1298 - Release Date: 25/02/2008 20:45 No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.21.1/1300 - Release Date: 26/02/2008 19:50

Moin, On Tue, 26 Feb 2008 19:22:58 +0100 Uwe Hermann uwe at hermann-uwe.de> wrote:

Actually that's is not true. There are many free/open FPGA boards,
programmers and programming software available. The FPGAs are well
documented on the external interface, so you could even build your
own programmer and write your own software easily. That is definitly
not the problem.

The problem lies in the bitstream files. Their format is not documented.
Which means, it would be "easily" possible to build a synthesiser that
produces an EDIF, you could even do some place and route based on the
specs in the data sheet, but you couldn't build a tool that would produce
a bitstream file to program the FPGA.



Hardware is available. There are lots and lots of FPGA boards out there.
Just google for them. Programming software for bitstream files is also
available.



You are definitly not the first one who wish for this.

Attila Kinali
--
Praised are the Fountains of Shelieth, the silver harp of the waters,
But blest in my name forever this stream that stanched my thirst!
-- Deed of Morred

Comments in your text.

At 01:22 PM 2/26/2008, you wrote:


No, you didn't miss anything. There are no open source FPGA/PLD chip
designs.




Yes, even ignoring the proprietary chips, there are no complete
development chains for PLD design. Most/all PLD vendors want to
protect their designs, so they keep secret the details of the
architecture as much as possible. That means there are one or two
pieces of software that are very hard to write.

The other pieces exist open source, HDL compilers, simulators and
even debugging tools.




The big obstacle to open source PLD chips is the cost. Software can
be developed a bit at a time by a lot of people so that none have to
contribute excessive amounts of time or money. Even boards can be
designed without excessive amounts of time or money (depending on
your definition of excessive). But chips are very expensive and time
intensive beasts to build. Chip design is only practical in larger
volumes. There are also any number of patent issues as this field is
full of patent land mines.

I believe there are places where you can get chips made as cheaply as
boards, but there are minimum quantities that make the total cost
significant.




This has been batted around in various forums before and it is not an
easy task. Think of it as designing your own CPU architecture like a
SPARC and getting the device made in addition to all of the support
software... no small task and no small expense.

Rick