CIA Question for FPGA Experts

[Plaz]

CIA chips are a common failure on amiga motherboards. I was wondering how much work would be involved in recreating CIA chips in FPGA for classic repairs. With pin out differences, I'm pretty sure a piggyback board would probably be needed. I'm thinking it could revive lots of 1200's and 4000's (maybe some CD32s). Perhaps even another version for 3000's.

Plaz

[Plaz]

Isn't this what Jens is doing with CloneA

Sure but that's a whole new machine with the entire machine probably in one big FPGA. This would be a much smaller project just for patching classics.

Plax

[Plaz]

@downix

Don't see why it would be that difficult. How about I mess with the MiniMig's limited CIA's and see if I can expand them to full complience?

Awesome if you could use minimig as a headstart. Minimig CIA should be similar to those used on A500/2000/3000. I don't know if the surface mount versions on A1200/4000 are different.

Plaz

[Plaz]

Not internally, no. Incidentally, the C128 had a CIA as well.

Same as the ones in Amiga? I might have guessed it would be like the one used in the C64, but functionally a bit different than the ones in Amiga. Interesting if they all used the same design just in differnt packages.

Plaz

[Plaz]

@Zac67

Thanks for the CIA lesson. Interesting about using 8520's in even a C64.

Are 8520s hard to get? Vesalia has them in stock for 6.90€ (DIL) or 3.90 (PLCC) - no way to beat that price with an FPGA!

I saw that today also. I wonder how their stock is holding up. Has any one made CIAs in 10 years?

Plaz