RPN scientific calculator firmware for $13 calculator kit

[jklsadf]

Yes, it's a pin-compatible drop in replacement. The only disadvantage is that when programming the flash, it takes longer to erase. To program a blank microcontroller, you have to add a couple of additional options to stcgal: -l 1200 -t 12000

Just as an update, haven't made any progress on anything, but hopefully eventually...