VHDL PDP11

On Nov 13, 2011, at 12:17 AM, Mouse wrote: That's great, and I'm with you in that I'd much rather see open source tools for this. However, the devices themselves and their configuration details are generally closely-held trade secrets, so closed vendor tools are what we've got. If you're not willing to run Windows or Linux to develop FPGAs, you better be satisfied with only simulation. I would love that. For my master's thesis, I'd hoped to gain some insight into the configuration bitstreams so I could configure the FPGA as a neural network dynamically. I got a very flat "no, and if you try to reverse engineer our bitstreams there may be trouble" answer from the major vendors. It would be nice to see someone make more open silicon, but without literally billions of dollars and thousands of employees, you couldn't hope to compete with the major players on performance (or even performance per watt), or in the marketplace. It's a sad aspect of the Free Market(tm), I guess. There is as much money and R&D poured into developing FPGA silicon as there is in memory and CPUs; those three are basically the main areas TSMC (and a few other foundries) focus their efforts on. There's always simulation. You can go a long way in simulation (in fact, you should) and have someone else implement it in an FPGA (if you've done your job right and read the synthesis manual, they shouldn't even need to tweak your code), and there are definitely open-source ASIC design tools. Icarus Verilog will even synthesize to a netlist intermediate, but that still requires closed vendor tools to turn it into a hardware implementation. I would also say that closed-source design implementation tools aren't as abusive towards the users as you might think; it's really just a proprietary translation using optimization algorithms they've spent millions of dollars on. While I think there's a case to be made that they could offer the source for money (like DEC did for most of their OSes), it would be a hard sell. You're welcome to lobby them; I'd support that effort. I think it could improve the ecosystem; I think the existence of cheap, GCC-based developer tools has bolstered the sales of ARM chips, for example, much more than Keil or IAR would like to admit. It'll be an uphill battle, though, because you have to convince the people who just want to make money that it will make them more money (I can tell you categorically that they are not interested in goodwill from the community, nor are they interested in hobbyists; they are interested in military and telecom sockets, because that's where their money comes from).

- Dave