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HP Forum Archive 08

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Aviation Pac and programming the 41CX
Message #1 Posted by John Breda on 20 Aug 2002, 6:24 a.m.

I posted a message yesterday but now was able to recall more about what I did 15 years ago. I used the aviation pac which works well. Additionally, I obtained some programs that were in the users library, one such program was number 1527C, HP 41C Flight Computer. It was designed to be used with the aviation pac defining user keys to start applications in the aviation pac and add additional calculations. The template I made was one shown in this program.

I tried to reload this program last night. I tried first via magnetic cards, and received card errors, and then tried from the bar code. Although the bar code seemed read in correctly, I was not able to run the progam afterward. First, I should check that the calculator is working properly. I seem to remember that there is a self-test sequence for the 41CX but do not recall what it is. Secondly, could anyone give me a quick outline as to how to enter a program via optical wand so I might check what I am doing.

The program requires 318 registers, so I am setting the size to 001. The I am simply entering via the wand, pressing GOTO.. after each program section. The catalog seems to reference all that it should, but when I define the necessary user keys, they can not find the program when activated.

Your assistance is appreciated.

Re: Aviation Pac and programming the 41CX
Message #2 Posted by Fred on 20 Aug 2002, 10:42 a.m.,
in response to message #1 by John Breda

I have never used a wand but if you press GOTO .. after each section this may include an END instruction between the sections, so local labels may not be solved !!!!

An idea, like an other ....


Re: Aviation Pac and programming the 41CX
Message #3 Posted by John K. (US) on 20 Aug 2002, 9:44 p.m.,
in response to message #1 by John Breda

Hmm. Using 318 out 319 registers doesn't really leave much room for variables... ;^)

I seem to recall that some of the larger programs had (at least) two parts. The first would set up the system, then prompt for another card. The second card would load the main part of the program, overwriting the original. Some of the really big ones would ask for different cards based on which part of the application was being used. Is it possible that the Flight Computer software is set up that way?

Re: Aviation Pac and programming the 41CX
Message #4 Posted by Vieira, Luiz C. (Brazil) on 20 Aug 2002, 10:32 p.m.,
in response to message #3 by John K. (US)


I do not know the program you mention here, but there is an instruction in the wand's repertoire that acts like MRG (merge) in the card reader, and other that acts like RSUB (read subroutine). Fred is right about it, pressing GTO . . while loading programs with the use of a wand will add an END in the last program in memory. But if you don't do it, loading the next program will overwrite the last one in memory that has no END (permanent .END. does not count as part of the last program).

The instructions available in the wand for loading a program is WNDLNK, and to load a subroutine is WNDSUB, but I do not have the manual in hands and I have never used them. Should you read about them and try some program loading.

Hope you have success.

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