Rainbow ponies for everyone!
No seriously, I'm really confused here. It makes no sense to recreate something that is already in plentiful supply. There are so many other things to be working on that pass the sniff test:
- An IDE controller that the Jr can boot from
- A memory expansion card using an SRAM chip or two instead of DRAMs. This is faster, lower power, and gets rid of the DRAM controller.
- An Ethernet card based on whatever the C64 and Apple ][ people are using. (Better, stronger, and faster than parallel port attach ones.)
- Another run of PCjr bus to ISA adapters so people can experiment with ISA cards on their Jrs.
- Updated BIOS or a BIOS ROM extension for 3.5" 720K floppy support.
- An upgrade to a 16450 UART instead of the built in 8250 UART
- A serial port card that goes in the modem slot
- An XT or AT keyboard adapter
Jrs are unwanted, low dollar machines - go adopt one today. Save the recreation work for 50 years from now.