Programming a HP41CX

[Bill Lafferty]

I am trying to re-create and alter an old HP41CX set of programs. I have a HP41CX in which I have installed X functions, 2/X memories.

I wish to alter a program which, after certain selections have been made, will read in another programm from a cassette. However, I cannot seem to enter manually the line "READP" instruction; in comes out with inverted commas around the instruction READP.

I have searched my manuals etc for comments on this, but to my sorrow nothing seems to solve this.

Another point - when the original program is called into the HP41CX from the cassette tape, the calculator beeps, but there is no beep written into the program. Can anyone explain this.

Thanks in advance

[Marcus von Cube, Germany]

I think, the READP function isn't installed anywhere on your CX. It should be in the IL ROM.

[Håkan Thörngren]

What is an inverted comma?

In order to enter an instruction, you use XEQ ALPHA name ALPHA. If the instruction exists, it will be entered without anything around it. If it is an rpn program (not a instruction), you will get XROM name. Otherwise you get XEQ name.

Thus, in order to enter an instruction, the instruction must be available when you key it. Plug in the HPIL module might help?

I guess the beep you hear when loading is the auto run feature. If you record a program with flag 11 set on a magnetic card, it will set an autorun flag. When loading the program, the HP41 will beep, then start the program just loaded without you pressing a key. I guess the same feature might be present on HPIL mass storage as well.

[Garth Wilson]

Quote:

---

I have a HP41CX in which I have installed X functions...

---

The 41cx has the extended functions built in. Adding it again in a module may cause problems. Others here who know the insides far better than I could tell you.

Quote:

---

I wish to alter a program which, after certain selections have been made, will read in another programm from a cassette. However, I cannot seem to enter manually the line "READP" instruction; in comes out with inverted commas around the instruction READP.

---

READP is in the HPIL module. It reads the program from mass storage and replaces the last program in main memory with this program. If you want to leave the last program in memory intact, use READSUB instead of READP. If the HPIL module is not plugged in when you key in the instruction, the 41 won't find the function, and assumes it's a label name you have added somewhere in your own programs. In the LCD, it will show up with a small raised "T" in front of it, but will print out with quote marks around it.

[Dan Grelinger]

1. As Garth said first, the HP41CX already has the Extended Functions module (and more) built in. Do not plug a separate one into the calculator.

2. This is a clarification of what Garth said about entering module functions when the module is not installed: It is best to enter the module function into a program when the module is installed. It will be entered in a manner that is very efficient to store and execute. The only downside is if the module is removed, it becomes more difficult to know what function is called, because the name dissappears and is replaced by something like XROM 21,02. But, you can enter in a function such as READP into a program, when the HP-IL module is not installed, and once you install the module, it will execute. The downside is it takes more memory to store the function in the program, and it executes slower.

3. As Hakan mentioned, the calculator beeping when a program is read in from tape, disk or magnetic card storage is an indication that it was recorded with the Auto-Execution flag (flag 11) set. If a program is saved whith Flag 11 set, the HP-41 will beep and begin execution when it is read back in. And yes, it works the same with HP-IL tape and disk storage as with mag cards.

Dan

[Bill Lafferty]

Many thanks to all who have responded to my queries, it has been of great help to me. It is very good to know that members of this group are there to help.
Kind regards
Bill in Cooma, Australia

[Stuart Sprott]

Hi Bill,

It's Stuart Sprott here. I think I sold you HP41 programs years ago.

I have since moved onto the HP 50 and and re written all the old programs and modified them. The HP 50 can do a lot than the HP 41.

Let me know if you are interested.

Regards,

Stuart.

[Bill Lafferty]

Yes, I remember you Stuart. Would you like to email me direct at nlafferty at ozemail dot com dot au?