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

[bxparks]

(03-15-2024 03:54 PM)Dave Britten Wrote:  Understandable, and I definitely wouldn't be able to tackle that either. But it would be a simpler approach to programmability than writing an entire keystroke-programming system, in any case.

It actually isn't obvious at this moment that shelling out to a TI-BASIC program is easier. That part of the TI 83 Plus SDK is not well documented at all, at least not to my eyes. Some very smart and dedicated people figured it out 20-25 years ago, but I don't know how much that knowledge has been retained. (Only one of the 3 shells that I referenced earlier makes the source code available.) Interacting with the TI-OS is always a long exercise of trial-and-error, since the official documentation is not always accurate or complete, and the undocumented features are scattered all over the internet.

The advantages of implementing my own keystroke programming is that I know and control the entire stack, up and down. I don't have to work around any undocumented and obscure bugs in the OS. The other advantage of adding my own programming is that there are features that have been added to RPN83P that are not available in TI-OS. The next version of RPN83P will include a bucket load of features which are completely outside of TI-OS.

The best thing would be to implement *both*, in other words, por que no los dos?