Wednesday, February 13, 2019

RetroChallenge 2019/03

RetroChallenge Updates:

Check out all of my RetroChallenge 2019/03 posts and updates.

RetroChallenge Goals:

Apple IIe Kim-1 Simulator (Kim-2e ?) Summary

I am really excited to finally get to do some work on an Apple IIe KIM-1 simulator. I don't have the money or space for a KIM-1, so this is as close as I am going to get. The end goal will be to have something that can run unmodified KIM-1 software. This will be tricky due to the conflicting address spaces between a KIM-1 and Apple II.
It will basically be a MOS 6532 RIOT IC on an Apple II peripheral card with some logic to enable it at the proper address locations. I will need to use an Apple IIe so that I can disable the built-in RAM at the addresses that KIM-1 software would expect the 6532. This RAM inhibit feature is not available on the Apple II+. I was considering including a ROM, but it will be easier to load the KIM-1 ROM data in Apple II RAM at the correct address. We will see how that works out. I am also considering using Mike Willegal's SuperProto card as a base for this project since the pinouts of the 6532 and 6522 are fairly close.
I don't think I will have time to build the keypad and display, but I may be able to add an RS232 circuit for user input.
Growing collection of Apple II and KIM-1 prototyping parts. 

No comments:

Post a Comment