< 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