HP41 TVM Program

[KD8TZC]

Does anyone know where I might find a program for the TVM calculation on the HP41? I know the advantage pac has this in it, but since I don't have that, I'd like to see if someone may have the code that I can manually enter.

Thanks

[Gene]

Here is the PPC ROM financial routine:

PPC ROM financial program for HP 41

and here is Tony Hutchins' improvement to it:

Tony Hutchins' FIN program

[Craig Bladow]

Also listed in the HP-41C Standard Applications Handbook.

[Dave Britten]

The Advantage Module TVM program is entirely user code, so you can key it into RAM if you like:

http://dave.brittens.org/HP41C/TVM-Advantage.txt

(Disclaimer: I can't remember if there were any LBLs/XEQs/GTOs in here that have to be changed due to not being ROM commands, or if I already did that in this listing.)

[AndiGer]

Dave,
Is this complete? Last statement I see is 390 (STO 7).
In statement 379 we got XEQ 05 that starts at 383. But what when the program reaches 390? 391 RTN?
Regards

[Dieter]

(05-29-2018 03:45 PM)AndiGer Wrote:  Is this complete? Last statement I see is 390 (STO 7).
In statement 379 we got XEQ 05 that starts at 383. But what when the program reaches 390? 391 RTN?

The final steps are OK. After STO 07 the program ends with an END command. This does the same as a RTN, so the latter is not required.

However, the program in the Advantage ROM has four more lines. The very first commands right after LBL"TVM" check if 10 data registers are available. If not, the user is prompted to set at least SIZE 010. This is accomplished by the "SZ" routine in the Advantage ROM. These lines (10 XEQ"SZ?" FC?C 25 PROMPT) are missing in the listing. If you want to duplicate this function you may begin the program like this:

Code:

01 LBL"TVM"
02 SF 25
03 "SET SIZE>=10"
03 RCL 09
04 FC?C 25
05 PROMPT
06 CF 00
07 LBL e
08 ...

If you got a 41CX or an Extended Functions ROM you can also set SIZE automatically, if required:

Code:

01 LBL"TVM"
02 SIZE?
03 10
04 X>Y?
05 PSIZE
06 CF 00
07 LBL e
08 ...

Dieter

[Ángel Martin]

You can also check the TVM ROM available at TOS (and in the CL Library, mnemonic "TVMY" located at 0x185).
It's an all-MCODE implementation that matches the 12C performance and speed.

http://hp41.deringenieur.net/file/TVM_1E%20QRG.pdf

The ROM also includes the Advantage's and the PPC's user code versions, so you have the three in a single pack.

[KD8TZC]

(05-30-2018 08:43 AM)Ángel Martin Wrote:  You can also check the TVM ROM available at TOS (and in the CL Library, mnemonic "TVMY" located at 0x185).
It's an all-MCODE implementation that matches the 12C performance and speed.

http://hp41.deringenieur.net/file/TVM_1E%20QRG.pdf

The ROM also includes the Advantage's and the PPC's user code versions, so you have the three in a single pack.

Hi Ángel, I'm sorry but you lost me at TOS. Sorry for being a little slow on what you are referencing.

[rprosperi]

(05-30-2018 07:22 PM)KD8TZC Wrote:  Hi Ángel, I'm sorry but you lost me at TOS. Sorry for being a little slow on what you are referencing.

TOS is shorthand (The Other Site) for another popular website exclusively about the HP-41, which can't be mentioned by name here (don't ask, it's not a very interesting story) but you probably now know what site that is.

[KD8TZC]

(05-31-2018 12:57 AM)rprosperi Wrote:  

(05-30-2018 07:22 PM)KD8TZC Wrote:  Hi Ángel, I'm sorry but you lost me at TOS. Sorry for being a little slow on what you are referencing.

TOS is shorthand (The Other Site) for another popular website exclusively about the HP-41, which can't be mentioned by name here (don't ask, it's not a very interesting story) but you probably now know what site that is.

Thanks... there are a couple of 41 sites and I don't ever recall seeing one that has a ROM though. I know one you can't see much unless you have an account (which I do not) so maybe that is the one. Okay, I will keep looking.

[Edit] created an account on that one site and I see it. Next question is this... what do I do with the ROM and how do I get it on the calculator. I assume I need some sort of interface which I don't have.

[rprosperi]

(05-31-2018 10:51 AM)KD8TZC Wrote:  Next question is this... what do I do with the ROM and how do I get it on the calculator. I assume I need some sort of interface which I don't have.

Although there are old-school (i.e. 80's) devices that you are probably thinking of, they are expensive and difficult to use, so today most folks use a 41CL, which is a 41 that has been upgraded with a replacement CPU board. If you want to seriously explore and use a 41, there is nothing else even close.

A 41CL has the max. RAM of a 41CX with full Ext. Memory, plus flash that contains > 512 different 41 ROMs, which can be virtually 'plugged-in' as needed. And as Angel's note implies, you can also add new ROM images as they are released.

Check out the 41CL here: http://www.systemyde.com/hp41/

[Dieter]

(05-31-2018 10:51 AM)KD8TZC Wrote:  [Edit] created an account on that one site and I see it. Next question is this... what do I do with the ROM and how do I get it on the calculator. I assume I need some sort of interface which I don't have.

Unless you own some special (non-HP) hardware the ROM is useless for a regular hardware HP-41C / CV / CX. The 41CL has been mentioned, but this is a different story, essentially a complete hardware upgrade of the innards of your calculator. However, you may use an emulator like V41. The latter comes with a variety of ROMs, including the Advantage ROM's and other TVM programs.

If you simply want to use your regular HP-41 take a look again at the listings of the Advantage ROM's TVM program. Please note that the program will not fit into a plain vanilla 41C, here at least one memory module is required. This limitation does not apply to the CV or CX.

You may also use the program that is included in the Standard Applications manual that came with your calculator. The listing (without any instructions) can be found here on this site. Set User mode, initialize with Shift [a], use [A] through [E] for n, i, PV, PMT and FV. Entering data with the digit keys stores the value, pressing the respective key without input calculates it. This program only supports "end" mode, while the Advantage ROM's lets you also select "begin" mode.

Dieter