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HP Forum Archive 06

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Pac compatibility
Message #1 Posted by Juan J on 24 June 2001, 11:19 a.m.

I have been using both the Petroleum Fluids Pac and the Advantage Pac on my 41CX. When I use the ROM functions of one of the Pacs, it affects the registers used by the other.

For instance, after using a base conversion function from the Advantage Pac, "IN2-M2" appears on the Alpha register. Similarly, the Z factor function corrupts registers allocated for matrices with null characters. And one day, after using the unit conversions of the Petroleum Fluids Pac I tried to solve an equation with the Advantage Pac. The calculator "froze." I turned it off and then tried to turn it back on. It refused. Only a memory reset brought it back to life.

I am the original owner of the calculator and never had a problem like this before. By the way, battery contacts were clean.

My question: is there an incompatibility between both pacs? If there is one, does it cause register corruption or a system crash? How dangerous it is?

Thanks

      
Re: Pac compatibility
Message #2 Posted by db(martinez,california) on 24 June 2001, 7:24 p.m.,
in response to message #1 by Juan J

it may be that the freeze up was not caused by the competing rom's. freeze ups happen. this might work: you could chose one of thoes applications and copy the global label that contains it's storage steps; mabye choose the shortest one, mabye the one with the fewest changes to make. then change the storage registers to ones that are higher than any others being used. since you don't change the label name the 41 will use your version - not the rom's - and they won't over-write data. when going in between rom functions, access them with goto instead of xeq. i don't know what to do about the alpha registers. good luck, i hope this helps.

            
Re: Pac compatibility
Message #3 Posted by Juan J on 25 June 2001, 11:40 a.m.,
in response to message #2 by db(martinez,california)

Thanks.

I'm having trouble with the ROM functions, not the programs. Both pacs have quite a few ROM functions, which are not user-accessible. It is these functions that are apparently conflicting.

The functions are, among others, unit conversions and Z factor calculations of the Petroleum Fluids Pac, and matrix functions and equation solver of the Advantage Pac.

As for the rest, I'll give it a try.

                  
Re: Pac compatibility
Message #4 Posted by Chris Catotti on 25 June 2001, 5:45 p.m.,
in response to message #3 by Juan J

With the HP-41CX, or Extended Functions/Memory Module on the 41CV or 41C, you have the ability to creat dsata files (CRFLD) and save registers (SAVER, SAVERX) and retrieve registers (GETR, GETRX).

This may be useful in avoiding "data corruption" by various application programs. Of course the Card Reader and HP-IL storage devices (cassette drive, disk drive) have similar features.

Regarding crashes ... ??? give me more specifics, whick functions, etc, and I could see if it does the same on mine.

                        
Re: Pac compatibility
Message #5 Posted by Juan J on 25 June 2001, 7:03 p.m.,
in response to message #4 by Chris Catotti

Chris:

Thanks. Last crash ocurred after I was doing unit conversions with the Petroleum Fluids Pac. Then I solved an equation with the Advantage Pac. After that I tucked my 41 in my pocket for a moment. (The pocket was big enough to loosely hold it, with no risk of accidentally pressing the toggle switches and/or the keys.)

I turned the calculator on and did a sum. When I tried to turn it off it beeped while the display showed "0.0000." It refused to shut down. I subsequently removed the batteries.

After putting the batteries back, the 41 refused to turn on. I retired the battery pack again and carefully removed the modules. Then I put the batteries back and did a system reset: the 41 came back to life.

It has worked well after that. Every now and then, however, the Z factor corrupts the registers allocated to matrices, and base conversions leave unit data on the Alpha register. This made me wonder about incompatibilities. Since Z factor, unit/base conversions and matrix functions are system functions and cannot be copied to user memory, you can't "fool" the calculator in this way.

I have made intensive use of the extended function and memory without any problem so far. In my opinion, it is a significant improvement over the 41C/CV function set.

Finally, it is worth noting that both the Advantage Pac and the Petroleum Fluids Pac have system utilities (that's HP terminology for them) for some applications. As far as I know, most of the other pacs have programs written in ROM, not system functions. Label conflicts can easily be avoided, but what about system function conflicts?

Thanks and regards.

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