The 6530-002 AND 6530-003 RRIOT (RAM ROM I/O Timer) are the heart of the KIM-1. The mask programmed ROM contains the KIM-1 software, very early and smart 6502 code.
These ICs are not available for a long time now, and that prevents repairing a KIM-1 with a faulty 6530.
Ruud Baltissen designed many years ago a KIM-1 clone, where the 6530 was replaced with the nearly identical, no ROM, 6532. This led to the MicroKIM, the PAL-1, the Corsham clone.
Also boards to replace the 6530 with a 6532, a small EPROM and some glue logic were made.
Bob Applegate and Eduardo Casino did this with PCBs and through hole components. Rather large boards that work fine.
Retrospy Technology used SMD to shrink the PCB to to a bit oversized 6530. Samll enough to fit on a KIM-1 in an IC socket.
Description from the Retrospy store:
Drop in replacement for impossible to find and replace MOS/Commodore KIM-1 specific MOS 6530 integrated circuit.
- Small footprint.
- Low profile.
- Configurable for either U2 or U3 via jumpers.
- Small enough that 2 can be used simultaneously in U2 and U3.
- Will fit over most socketed RAM.
- Requires MOS 6532 RIOT IC to be installed.
- Requires a socket at U2 and/or U3.
Jumpers on teh board switch between 6530-002 and -003.
