In article , Joerg wrote: [...]
I've had to figure out the circuit from something with removed numbers. It took me about an hour. BTW: I was repairing something.
The fun thing about the ASCI is that they have to run signals in and look at the output. If things are a non-linear function of the past, figuring out what a circuit does can be tricky. Think about characterizing an AGC system. It is a lot harder than a simple filter.
The problem with the FPGA idea is that the boot up stuff is not stored right in the chip so it is very insecure. I don't know of a normal DSP that doesn't also have this problem. A DSPic may be the answer for some of the circuit.