Running out of labels on HP-15C

[Pekis]

Hello,

Mostly in HP-15CE in 15.2 mode, there is a great risk of running out of labels one day or another.

EDITED: See update below

[Pekis]

Hello,

Mostly in HP-15CE in 15.2 mode, there is a great risk of running out of labels one day or another.
Nevertheless, you could get around that this way I think, inspired by an old thread: (GSB I bug)

The idea is to use one label for branching with GTO i.
It has the advantage of not disturbing the stack nor the conditional branching flow, but you have to update the destination line numbers in case of later line inserts...
What do you think of it ?

First example (with simple subroutine):
...
STO i (Save current x)
RDOWN
800 (Destination line number)
CHS (To allow a jump to line number with GTO i)
x<->i (Restore x and save i)
GSB C (GSB line number 800 actually)
...
Line number 800: The called simple subroutine
...
RTN

Second example (with conditional branching):
...
STO i (Save current x)
RDOWN
270 (Destination line number)
CHS (To allow a jump to line number with GTO i)
x<->i (Restore x and save i)
x<0? (example test)
GTO C (GTO line number 270 actually)
...
Line number 270:
...
...

LBL C: (Branching subroutine, used by both examples)
GTO i (Jump to line number)

[spa1fwg]

I have to try what you say and see if it works or not!
If it works it would be perfect!!!

[Maximilian Hohmann]

Hello!

(08-07-2023 12:24 PM)Pekis Wrote:  What do you think of it ?

Very clever, but that's one of those things that makes you proud for a short while only. When you want to change the program in a year from now, or, heaven forbid!, give it to somebody else, you or he will have a very hard time to figure out how it is supposed to work...
When I run of labels or programming steps I take this as a hint that I am using the wrong tool for the job ;-)

Regards
Max

[Pekis]

(08-23-2023 04:27 PM)Maximilian Hohmann Wrote:  Hello!

(08-07-2023 12:24 PM)Pekis Wrote:  What do you think of it ?

Very clever, but that's one of those things that makes you proud for a short while only. When you want to change the program in a year from now, or, heaven forbid!, give it to somebody else, you or he will have a very hard time to figure out how it is supposed to work...
When I run of labels or programming steps I take this as a hint that I am using the wrong tool for the job ;-)

Regards
Max

I think I'll remember how it works because it's simple (GTO i without disturbing stack) but if you ever have to insert code, you need the Excel file to check and modify all the possible dependent GTOs: you feel like a linker in a minefield, a rather embarrassing situation ...
Though, once the tool is calibrated, enjoy it !

[Eddie W. Shore]

The HP 33S and possibly the DM32 have the same label problem, without the option of going to a line number.

[Ross Barnes]

There are old programming forms for the 25, 65, and 67 on literature.hpcalc.org. I find the printed form and a pencil with eraser is a low tech way to document programs for calculators (e.g. 15C) with key codes and/or line numbers. The form gives a quick way to recalculate the line number for any indirect line jumps that use Pekis's method above when the entire program is moved in memory. I try to keep individual programs short enough to theoretically fit in a HP-25C or HP-29C to avoid the situation mentioned by Maximilian Hohmann about "using the wrong tool for the job." The HP-15C has memory for a few such programs.

[Matt Agajanian]

Hi all. You lost me at 800 for a line number. How can an 800 step program be possible with 448 bytes on the C and 672 bytes on the CE?

I thought, just as the 29C, 67/97, the 15C stars look downward from the label call to search for labels?

[Gene]

Read up Matt.

The CE has some hidden tricks. It’s all described in the main big 15C CE thread.

[Matt Agajanian]

Will do. Thanks!

[Steve Simpkin]

(08-25-2023 12:35 AM)Matt Agajanian Wrote:  Will do. Thanks!

Here is information about the additional firmware "Modes" available in the HP-15C CE.

The HP-15C CE contains 3 firmware version "Modes" in its Flash memory. These are labeled 15C, 15.2C and 16C.

15C mode is the "normal" HP-15C mode (with 672 bytes of memory).

15.2C mode has even more memory available (approx. 1300 bytes).

16C mode operates as a HP-16C calculator (note the key labels do not match what is printed on the HP-15C so an overlay and keys stickers would be required to easily use this as a HP-16C calculator).
Note the extra 15.2C and 16C modes are not supported by the manufacturer.

To switch firmware "Modes", start with the calculator Off
Press and hold [g] and [ENTER]
Press [ON]
On screen: 1.L 2.C 3.H
Press [4]
On screen: 15 15.2 16

Then:
Press [e^x] or [10^x] -> 15C mode
Press [y^x] or [1/x] -> 15.2C mode
Press [CHS] or [7] -> 16C mode

[Matt Agajanian]

(08-25-2023 02:55 AM)Steve Simpkin Wrote:  

(08-25-2023 12:35 AM)Matt Agajanian Wrote:  Will do. Thanks!

Here is information about the additional firmware "Modes" available in the HP-15C CE.

The HP-15C CE contains 3 firmware version "Modes" in its Flash memory. These are labeled 15C, 15.2C and 16C.

15C mode is the "normal" HP-15C mode (with 672 bytes of memory).

15.2C mode has even more memory available (approx. 1300 bytes).

16C mode operates as a HP-16C calculator (note the key labels do not match what is printed on the HP-15C so an overlay and keys stickers would be required to easily use this as a HP-16C calculator).
Note the extra 15.2C and 16C modes are not supported by the manufacturer.

To switch firmware "Modes", start with the calculator Off
Press and hold [g] and [ENTER]
Press [ON]
On screen: 1.L 2.C 3.H
Press [4]
On screen: 15 15.2 16

Then:
Press [e^x] or [10^x] -> 15C mode
Press [y^x] or [1/x] -> 15.2C mode
Press [CHS] or [7] -> 16C mode

Seems essential to keep in mind! Thanks!

[Thomas Radtke]

(08-23-2023 04:27 PM)Maximilian Hohmann Wrote:  When I run of labels or programming steps I take this as a hint that I am using the wrong tool for the job ;-)

That's why I can't be bothered to switch to the other mode. Honestly, I was always happy with the 32SII. All those calculators do much more than I expect from them. That's a good thing.

But it's part of the fun to devise clever methods to expand the possibilities.