HP35s / RPN Calculator Simulator in Excel / Java?


Has anyone seen (or perhaps already done) a RPN calculator/simulator in Excel(VBA) or Java?

My particular interest has been picqued by writing code for the HP35s and wanting to be able to see the data memory as the algorithm was executing.

While there are several simulators(even bit-accurate emulators) out there for various machines, I was thinking it would be nice to have a simulator, for example the HP35s where one could not only see the full stack, but all (or many - perhaps 100) data memories while code is executing to see the movement of data while the algorithm executes. I've begun this process (in Excel97) and was curious if perhaps this has been done already - or if anyone else out there would have a need for such a piece of code. Certainly, Java would be more universal, but I'm currently more conversant in Excel(VBA).

Thoughts and opinions appreciated,

( I also posted in comp.sys.hp48)


I am not joking...

I am trying to write one right now (java) as I type (well not *exactly now*...).

And my reasons are yours! Thing is, I got ideas for HP35s programs, not gonna have it for months it seems, so need simulator...

Well, writing simulators are tedious stuff... AND to get it right you need very exact documentation and time to study it... I dont have that :-(

So my approach is to *try* write a generic rpn hp calculator with the stuff I need for my programs AND try to match it according to what I can understand of the machine by online doc.. (HP, anytime now would be ok for that manual pdf to be posted).

Propably fail, but if not will put stuff up as open source...

What as a simulator/emulaotor wannabe would like would be a database of hp calc operation normalized by name, brand and description (exact) operation.

Well, nuff posting, back to hacking...



pleaswe take a look at

RPN Calc simulations




Thanks. Yes,these are fine simulators - even bit-accurate in most all cases.

My need here is more driven - not so much by an absolutely accurate model of the machine - but by being able to watch the machine perform while executing steps in a program. I am writing some code for the HP35s to do Matrix operations, and ascertaining that my code is using data memory properly, I need to 'see inside' the machine while the data is being moved around and modified. Checking that a 5x5 or 10x10 matrix has been moved and/or operated on via the HP35s display is a bit tedious. I can see all 100 or so memories simultaneously on a spreadsheet.

I've gotten the basic code done for stack and data operations done. Doing the program interpretation is going to be significantly more tedious.



What code 'done' are you talking about? I would be interested!



I am working on an RPN2 simulator in Excel (and Excel VBA). This is a version of RPN that support paged variables (single variables and matrices), global labels, and local labels. The result is the ability to write subroutine that have their own variables that don't necessarily clash with other routines that use variables with similar names (but associated with a different page name). I designed RPN2 to allow a routine to switch page name (as many times as you wish) and access variables in different pages. Also, RPN2 has global and local level labels, goto commands, and subroutine commands.

My intent is to create a new version of a programmable RPN engine that can compete with RPL.

RPN2 supports single numeric variable, flags, strings, and also matrices. I am tapping into Excel's commands to support matrices without slowing down the interpreter.

I am working on the documentation and that will take a while.



Hello Namir:

Your project sounds most interesting!!! Would like to know more as it becomes ready.

My current project is very simple - only real numbers (for now - I really do need smooth complex number handling). I anticipate that extending it to 3D vectors as the 35s does will not take too much effort. My demand was driven to 'see' what is going on inside my HP35s while solving matrices and manipulating significant blocks of memory.

I am using Excel97 and VBA. Thus the application will run across many (more modern) Excel platforms. Should speed become an issue, I may use VB4 or VB6.


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