HP-67/97 TIDES CALCULATIONS

[plore90]

Hello everyone,
here I am again to present my library of programs that I developed for HP-67/97, ​​regarding "TIDES CALCULATIONS", a series of magnetic cards that have as their object the prediction and calculation of the tides, both for fishing and for navigation. There are also three .zip files (OneDrive Link
https://1drv.ms/f/c/5e1e59b5c21225c8/En6...A?e=fYeBRK)
Sailing with the Tides PDF1.zip, Sailing with the Tides PDF2.zip, Sailing with the Tides PDF3.zip that contains the theoretical part and the exercises from which I was inspired to create the programs of the library. For each magnetic card there is the .hp97 file that as usual can be used with the two freeware emulators HP-67 and HP-97 by Mr. Michael O'Shea (LimpidFox.com) and the corresponding .PDF listing. In addition there are some magnetic cards that contain the preloaded data for the calculation examples. In the attached Manual "HP6797 TIDES CALCULATIONS MANUAL.txt" there are the instructions for using the various programs. As always, I will be grateful to those who will test the various programs and report any errors. Everyone will be able to modify and expand the programs as needed.
This is the Italian site where I got the formulas for my tide calculation programs:

http://navigazione.altervista.org/maree-2/

I hope they can be useful to some of you.
Thanks for your attention
plore90

[floppy]

Interesting. On my ToDo is a tide calculation for water around France and around Ireland for HP41 or HP71 Forth. Anything is in the files for making this?

[plore90]

Hi Floppy,
I think so, I developed it for the HP-67/97 but they have few programming steps, the programs can be expanded for the HP-41 and other more powerful ones. This is the link I used to develop my programs, it is in Italian language, but with Google translation it is possible to read it in English. It is very interesting for tide forecast calculations...

http://navigazione.altervista.org/es-nav...o-altezza/

plore

[plore90]

Calculate the tide height in meters at a given time tf(hh:mm) for a Secondary Port knowing the tidal data of the Main Port.

Main Port:
Low Tide t = 13:47 h = 0.60 m
High Tide t = 19:54 h = 4.55 m
Secondary Port: Corrections
Low Tide t = -00.05 h = +0.10 m
High Tide t = -00.20 h = +0.25 m
Secondary Port Pa = 1003 ePascal

1> Step : 13.47 STO1
0.60 STO2
19.54 STO3
4.55 STO4
P<>S
-00.05 STO6
+00.10 STO7
-00.20 STO8
+00.25 STO9
P<>S
2> STEP : READ PROGRAM CARD HP6797 TIDES_SPORT.hp97
I have the Tide data loaded with the sequence Low Tide -> High Tide
then I press the B key
I get the Tide data for the Secondary Port
3> STEP : I load the Atmospheric Pressure of the Secondary Port (1003) because it is different from the standard value 1013

1003 STOI

4> STEP : I have the Tide data of the Secondary Port with the sequence Low Tide -> High Tide
so for the calculation required by the problem

READ PROGRAM CARD HP6797_TIDESBABA.hp97
I insert the desired instant tf(hh.mm) in the R9 register
ie. 16.10 STO9
then I press the A key
I get the value of the height of the corresponding Tide without atmospheric correction x= 2.26 m
I have a value in the I register different from 0.00
then I press the B key to obtain the correct value of the height of the tide at that Pa
i.e. x= 2.36 m.

If I have to calculate the instant tf at which I have a given height, I have to repeat the same STEP 1 and 2,
then I skip to step 4 and I go to read the magnetic card, this time, HP6797_TIDESHTBA.hp97
I store the height provided h in meters, in the register R0 (h STO0) and then I press the A key, obtaining the value of tf(hh.mm) requested.

Plore90