Not enough ports? Make two ports out of one using this!
Insert this small module into one of the cartridge slots to easily add a power led and reset button to your system.
This cartridge PCB lets you use MMC/SD cards as a removable storage medium for your PCjr and can even replace a hard drive!
Update your SD-Cart JR with this new boot ROM which supports the use of other hard drives on the system, such as a jr-IDE.