RPN83P: RPN calculator for TI-83+ TI-84+ inspired by HP-42S

[jthole]

Communicating via the registers (and stack) already works fine between TI-Basic and RPN83P.

PROGRAM:STOREG
Prompt R
Prompt V
V -> lREGS(R+1)

(TI-OS)
prgmSTOREG
V=?123
R=?0

(RPN83P)
RCL 00
123

Edit:

Of course you can do that from the TI-OS home screen as well (instead of from a program). What is nice as well, is that you can use the Ans variable (corresponding to LastX in RPN83P) in the TI-84+ solver too.

So the STK, REGS, and Ans (list) variables are really the link between the RPN calculator part, and the remaining TI-84+ functions.