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HP Forum Archive 19

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HP 30B Keyboard Overlay ... really?
Message #1 Posted by Jim Yohe on 6 Nov 2010, 12:20 a.m.

In Gene Wright's article, "The HP 30b Business Professional", published in the HP_Solve_Issue_18_April_2010.pdf, he states, "To help the user who wants to write programs more easily remember the command locations, a clear, thin, sticky overlay is provided which lays over the top four rows of keys.".

I just purchased my own HP 30B and didn't find an overlay. I wonder when these overlays were available. Hmmm.

      
Re: HP 30B Keyboard Overlay ... really?
Message #2 Posted by Tim Wessman on 6 Nov 2010, 12:35 a.m.,
in response to message #1 by Jim Yohe

Look inside the quickstart guide.

TW

            
Re: HP 30B Keyboard Overlay ... really?
Message #3 Posted by Jim Yohe on 6 Nov 2010, 12:52 a.m.,
in response to message #2 by Tim Wessman

Just did (again) and didn't find it. Did you find it there?

      
Re: HP 30B Keyboard Overlay ... really?
Message #4 Posted by Mark Harman on 6 Nov 2010, 12:57 a.m.,
in response to message #1 by Jim Yohe

Tim is right. More precisely, it should be somewhere in the back of the Quick Start Guide.

I also recommend downloading the full manual and learning guides from the following links. I consider them valuable resources.

http://commerce.hpcalc.org/HP_20b_30b_User_Guide.pdf

http://commerce.hpcalc.org/30b_Learning_Modules.zip

Regards,

Mark

Edited: 6 Nov 2010, 1:00 a.m.

            
Re: HP 30B Keyboard Overlay ... really?
Message #5 Posted by Jim Yohe on 6 Nov 2010, 1:24 a.m.,
in response to message #4 by Mark Harman

Found it. Had to retrace my steps (fell out next to a chair). Also, I downloaded the full User Guide and learning modules earlier. Had a look at all of them before deciding to make the purchase. Thanks.

                  
Re: HP 30B Keyboard Overlay ... really?
Message #6 Posted by Mark Harman on 6 Nov 2010, 1:36 a.m.,
in response to message #5 by Jim Yohe

As a word of warning, there are some errors in the learning modules. I can't recall where they are at, though. However, you should get the main idea of what you need to do from them.

I think you will come to find, as I have, that the 30b is quite an amazing calculator. I have come to really appreciate is its high level of functionality as well as its blazing fast speed.

Regards,

Mark

                        
Re: HP 30B Keyboard Overlay ... really?
Message #7 Posted by Kiyoshi Akima on 6 Nov 2010, 2:13 a.m.,
in response to message #6 by Mark Harman

I've found one problem that, while technically not an error in the learning guides, I consider an error in the calculator itself.

If you've set the display to FIX -1 mode, RCL MODE will return that as 13. However, when you want to set it this way, STO MODE requires it to be 12. If you set it to 13, the calculator rejects it and leaves the display mode unchanged. This means that if you do a RCL MODE, save the 12-digit number somewhere, change the settings, then do a STO MODE with the saved value, you won't necessary get the original display mode restored.

As I said, this is not an error in the guides, since they and the manual do give the values as 12 and 13. But who the heck designed it so that recalled value can't be used to restore things?

                              
Re: HP 30B Keyboard Overlay ... really?
Message #8 Posted by Katie Wasserman on 6 Nov 2010, 10:05 p.m.,
in response to message #7 by Kiyoshi Akima

I agree that this is not consistent behavior that makes it difficult to save the state of the mode flags in a program then restore them when the program finishes.

However in defense of the 30b, I think that the ability to recall and save the state of the decimal places, entry mode and other settings in a single register is a very nice feature to have on a low-end programmable calculator.

-Katie

                              
Re: HP 30B Keyboard Overlay ... really?
Message #9 Posted by DeboT on 10 Nov 2010, 10:32 a.m.,
in response to message #7 by Kiyoshi Akima

I also have a problem with the FIX mode. When set to -1 it will display all the zeros for numbers >=1E12, i.e. 1.0000000000 12. It does not do this for numbers <=1E-12. Would you consider this a bug?

                                    
Re: HP 30B Keyboard Overlay ... really?
Message #10 Posted by Katie Wasserman on 10 Nov 2010, 11:41 a.m.,
in response to message #9 by DeboT

FIX -1 mode is not the same as the ALL mode in previous HP calculators, although it acts like that when not in scientific notation mode. When the 30b switches to scientific notation to show 1E12, for example, it shows as many decimal paces as requested and FIX -1 means whatever fits on the display.

It's hard to call this a bug based on past HP calculator expectations especially since the manual says:

Quote:
If you specify 1, the calculator displays numbers with the most appropriate number of digits after the decimal point

"Appropriate" being in the eyes of the firmware developer not necessarily the user.

-Katie

                                          
Re: HP 30B FIX -1
Message #11 Posted by DeboT on 10 Nov 2010, 1:17 p.m.,
in response to message #10 by Katie Wasserman

But for negative exponents it does not display those zeros. So there's inconsistency at the very least. Anyway, it's not a problem as such, just "doesn't look nice".

                        
Re: HP 30B Keyboard Overlay ... really?
Message #12 Posted by gene wright on 6 Nov 2010, 7:09 p.m.,
in response to message #6 by Mark Harman

Yes, there are 2 (I think) errors in one of the learning modules that slipped through.

Not sure what it would take to get the PDF files replaced, however.

                              
Re: HP 30B Keyboard Overlay ... really?
Message #13 Posted by Kiyoshi Akima on 6 Nov 2010, 8:30 p.m.,
in response to message #12 by gene wright

Is there a bug list for the 30b? I have a contribution.

RCL arithmetic doesn't work properly for the Cashflow registers. You can put an instruction like RCL+ Cashflow into a program, but when executed (either in a program or from the keyboard) simply performs a RCL Cashflow without doing the arithmetic.

                                    
Re: HP 30B Keyboard Overlay ... really?
Message #14 Posted by Jim Yohe on 6 Nov 2010, 9:19 p.m.,
in response to message #13 by Kiyoshi Akima

You've already pointed out a couple. Where would a bug list be kept at?

                                    
Re: HP 30B Keyboard Overlay ... really?
Message #15 Posted by Katie Wasserman on 6 Nov 2010, 9:57 p.m.,
in response to message #13 by Kiyoshi Akima

I don't think this is a bug, sto/rcl arithmetic is not suppose to work on the indirect (i.e., cash flow and data) registers. The manual doens't say that it does, it only mentions sto/rcl arithmetic in conjunction with memories 0 - 9.

There are some other key sequences that you can put into a program that don't have any effect. This is an 'artifact' of the macro recording mode of programming and the way STO/RCL try to merge keystrokes for display purposes. I'm not sure that this is a bug either, just undocumented behavior.

-Katie

                                          
Re: HP 30B Keyboard Overlay ... really?
Message #16 Posted by David Hayden on 9 Nov 2010, 11:26 a.m.,
in response to message #15 by Katie Wasserman

Quote:
I don't think this is a bug, sto/rcl arithmetic is not suppose to work on the indirect (i.e., cash flow and data) registers. The manual doens't say that it does, it only mentions sto/rcl arithmetic in conjunction with memories 0 - 9.

There are some other key sequences that you can put into a program that don't have any effect. This is an 'artifact' of the macro recording mode of programming and the way STO/RCL try to merge keystrokes for display purposes. I'm not sure that this is a bug either, just undocumented behavior.

-Katie


Undocumented behavior is always a sticky area when it comes to deciding if something is a bug or not. I understand that the STO/RCL arithmetic isn't supported with the cashflow registers, but it really should reject the command rather than silently doing something else.

I think it's a bug because it's something that a user is reasonably likely to try. It's better to give them an error than to silently give them some related but unexpected functionality.

Dave

                                                
Re: HP 30B Keyboard Overlay ... really?
Message #17 Posted by Don Shepherd on 9 Nov 2010, 12:32 p.m.,
in response to message #16 by David Hayden

I agree with Dave. If program mode accepts these as seemingly valid commands, as it does, then that is wrong. Bug.

                              
Re: HP 30B Keyboard Overlay ... really?
Message #18 Posted by Jim Yohe on 7 Nov 2010, 11:40 p.m.,
in response to message #12 by gene wright

Hey Gene, I'm not sure if I found the two errors you are referring to in this one learning module or of there is another one that I haven't run across yet but in the "HP30b 33Trigonometry.pdf" file Example 4 has compound problems.

The solution is flawed in two ways. In this example the author creates an input to the arcsine (ASIN) function that falls outside of its domain and so therefore fails. The user is instructed to divide 6 by 3 which results in 2 and to take the arcsine of this number. The valid domains for arcsine (ASIN) is (-1,+1), arccosine (ACOS) is (-1,+1), and arctangent (ATAN) is (-infinity,+infinity) so 2 clearly falls outside of ASIN's domain of (-1,+1).

Now to identify the real problems:

1) You are given only dimensions for the (opposite and adjacent) sides of this right triangle not the (opposite and hypotenuse) sides which is required by the arcsine function. The only function that will work with these two sides is arctangent;

2) If you are to use this function and the angle is from the ladder to the wall (up where the ladder contacts the wall), then you need to divide 3 by 6 not the original 6 by 3.

Therefore the solution is:

Angle = ATAN(opposite/adjacent) = ATAN(3/6) = ATAN(0.5) = 26.56 degrees

                                    
Re: HP 30B Keyboard Overlay ... really?
Message #19 Posted by Jim Yohe on 7 Nov 2010, 11:52 p.m.,
in response to message #18 by Jim Yohe

Funny ... I just realized there are two Example 4's in that one PDF file. A minor error but that makes three.

                                    
Re: HP 30B Keyboard Overlay ... really?
Message #20 Posted by Jim Yohe on 9 Nov 2010, 7:17 a.m.,
in response to message #18 by Jim Yohe

I'm such a fool and will eat crow by admitting that part 1 of my argument is patently false. The problem originally posed that the length of 6 meters was of the ladder, the hypotenuse, not my incorrect reading as being the height from the floor to the where the ladder contacts the wall.

Therefore we still use the arcsine function but it must be of the opposite side divided by the hypotenuse:

Angle = ASIN(opposite/hypotenuse) = ASIN (3/6) = ASIN (0.5) = 30 degrees


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