< Most Xilinx FPGAs can be configured by a serial bitstream from a
< microcontroller or a PC printer port. Not too hard to do, and a lot
< easier to modify than an EPROM.
I use EEproms... easier still. They can also take a serial bit stream
but in some apps the controller isn't operable until the FPGA is up.
< The problem with most of these devices is that the format of the
< bitstream is not documented (in fact some companies actively prevent it
< being documented) and that you have to use their expensive software
< (which often runs under an OS that I don't have...). However, take a loo
< at the Xilinx 6000 chips - they are 100% documented. It's possible to
< write your own compiler and downloader for these. They also look
< interesting devices...
Most the serial format is easy and a loader is not much but the compiler
is not trivial as you have to do route maps and that's not trivial.
< Take a look at the PICs as well. The programmer for those is very simple
< and Microchip do document the programming algorithms. A 16C84 programmer
< is 2 cheap TTL chips, a few discretes and a PC printer port.
I've looked at them and like most single chips MCUs they are bizzare.
They also offer a windows emulator that pretty neat.
Allison