www.SwissMicros.com

No mystery, as the OP says it's all the same page, https://www.swissmicros.com/models.php, which is about the various models. Scroll (up and) down and you will see all the places to request to be notified.

You can enter the page at different points and the end of the url reflects the entry point.

Ah... I see now that this is directly related to your project to 'compile' existing code (btw, coming along nicely!) so I agree my suggestion isn't helpful for that use. My suggestion about flags - I was thinking of using a single LBL/RTN subroutine which would dispatch to a series of other places v...

How would you go about writing your own gosub stack? Do you mean use GTO I with flags and such to simulate a GSB/RTN ? Not sure, one way would be to put the stack pointer in register 0, having it contain the register number that contains the line number to jump to on return. There is an easier work...

but a Gosub to an arbitrary line number is poor programming so they probably prevented it. Not if you only use this to jump to specific line numbers because you ran out of labels. In any case though the DM15 should clearly behave the same as genuine HP-15Cs. Personally, I think it should behave lik...

This seems to be a bug of the original 15C firmware that was fixed by changing the manual to remove the reference to GSB I with I<0. See this discussion . Nice find Didier. I tend to agree with Message #11 Posted by Michael de Estrada in that thread. GSB is intended to go to a labeled routine that ...

I voted for (b) for 2 reasons. Consistency both with the classic machines we are trying to emulate (and improve) and also with the rest of the 43S key labels (Enter, STO, RCL, PROG, LOOP, etc.). But also because of the issue Didier explained so well. Even with the superb LCD contrast we've seen on t...

I'm glad you took my comments in the spirit intended. I think you make a good case, and would agree that a limited attempt to correct this limitation by simply changing the 'max line number' constant is justified. If it is that simple (from an immediate 'yes that single change seems to work' viewpoi...

Right, but SwissMicros don't have the source code, just the ROM (I think) No one, including HP, has the 15C source code any more... A good question to ask though is how important is this really? DM15's (both cc and L flavors) have been sold for 5+ years, and this is the first time this has even com...

Thanks for the hint, I updated to DM15 M1B V28 and still get the same error (Can't jump to line numbers above 448, neither with GTO nor with GSB) I suspected not, but at least now it's clear. I'm sure it is indeed a limitation of the ROM code that only envisioned a certain amount of RAM. Though SM ...

Suggest you update the f/w in your DM15. It appears you are running V25, but there have been 3 releases since then, including at least one fix which corrected (a possibly unrelated) bug pertaining to extended memory access for the DM15_M80 and DM15_M1B configurations. I'm not saying this will fix th...