FPGA file formats

These are all secret. If you will use FPGAs you have to accept that you will be able to work only with the high-level programming tools available for the respective silicon. Same is valid for the CPLDs - although at least there you can - under NDA - get the fusemap translation JEDEC -> JTAG sequence, at least this is valid for the Coolrunner CPLD.

Dimiter

------------------------------------------------------ Dimiter Popoff Transgalactic Instruments

------------------------------------------------------

you mean, even the name of the file format is kept as a secret by the company? or is it the mapping of the fusebits to the different bits in the file format?

i was planning to implement a programer that would work with any fpga

regards cherin

Why do you assume they would have bothered with giving it a name in the first place?

The fact that you're asking here pretty much guarantees that the chip vendors won't give you the necessary information.

I would not know. How they call their secret internal data is beyond the scope of my interest.

That's definitely secret. I know of no alternative source of FPGA and of only one for CPLD programming software. The latter is my lc for DPS for the original (Philips) coolrunners - and I had to do some significant reverse engineering back then to get to all the data I needed to do it.

You are unlikely to get much beyond good luck wishes from anyone; you have mine. Other than that you will be on your own. I would be curious to see your results if any in a years time.

Didi

------------------------------------------------------ Dimiter Popoff Transgalactic Instruments

------------------------------------------------------

Original message:

Afaik, FPGAs were only reverse-engineered once: NeoCad put out a

3rd-party CAD suite for some of the Xilinx parts. Their tools were better than Xilinx, so Xilinx bought them, & everything went back under wraps again.

Still, not a totally unpleasant outcome for the 3rd party - especially if they paid a reasonable amount for it.

Cth

You have to differentiate between a 'compiler' type of function and a 'downloader' type of one.

The information to write a compiler is closely held - NDA, or worse.

The information needed to download bitstream files produced by official tools is quite a bit more accessible, usually published by the manufacturer for some formats (possibly even with example source code), or often already reverse engineered by someone.

In addition to a variety of HDL source file formats, configuration files, and output file options, there are also a metric ton of proprietary, partially understood, and fully specified intermediate files unique to each tool flow. Listing them all would be a lengthy exercise!

In my experience it has always been "worse", and I have been asking. Around 2000 I even thought I had all the info I needed from Philips on their Coolrunners and designed some in - only to discover I was missing an important piece of data (the multiplexor addressing scheme). It took writing a specific software to reverse engineer that, a few weeks of serious work.

Yep, that's what Philips had given me back then without an NDA. Until recently Xilinx would not give even that even under NDA, but this changed for the better since my latest thread on that in comp.arch.fpga .

Didi

------------------------------------------------------ Dimiter Popoff Transgalactic Instruments

------------------------------------------------------

Original message:

Well, "thanks" to the DMCA and similar legislation, these days they most likely wouldn't receive a single dime. They'd just get their pants sued right off 'em. They might have to consider themselves lucky if they can avoid a jail sentence.