HP-15C CE documentation

[AnnoyedOne]

I think that naddy asked this question but I cannot find the post. As far as I know there is no public HP-15C CE documentation errata list available. If one exists it is private.

I do know of at least one error in the CE Advanced Functions Handbook (27th July 2023). I think there's another one but I don't remember where. The one I know of is minor as was the other as I recall.

Whatever the case my CE Owner's Handbook and Advanced Functions Handbook PDF's show "HP Inc" as the author and the PDF producer as hpcalc.org.

As far as I can tell the versions on that site haven't been updated. Nor anywhere else that I've seen.

https://literature.hpcalc.org/#lang:English/model:15C

A1

[naddy]

There is a mistake on page 113 (PDF page 125) of the Owner's Manual. At the bottom of the page in the keystrokes section, it gives the loop counter as

Code:

3.000001 STO 2

This clearly should be

Code:

3.00001 STO 2

since the loop counter format is nnnnn.xxxyy. This typo must have slipped in during editing, because it is not present in the original. The example will still work, though, since an increment of 00 is equivalent to 01.

I think I noticed one or two spelling/grammar typos in the Advanced Functions Handbook, but I didn't keep notes, sorry.

[Eric Rechlin]

I cannot remember any errors being reported about the AFH, so if you have found one, please let me know so I can correct it.

In the OH, there was one known mistake. This was not a mistake in the original HP-15C OH, but it was introduced in the HP 15c LE OH and not corrected for the HP 15c CE OH. This is on page 178, where, in the middle of the page, it says "RCL DIM (A through E, (i))" instead of "RCL DIM (A through E, I)". This was reported to me by Valentin in September of last year.

I was previously unaware of that additional typo on page 113, which also was inherited from the 15c LE OH, so I guess that makes 2 errors in total. I have corrected that in my copy. Thank you, naddy!

At some point I would like to make a new edition of the 15C CE OH. I was hoping to get the first above error corrected for the second production run of the 15C CE but that wasn't possible, so there only exists the one edition at the moment. If I make a new edition, I would also like to update any wording about limitations of memory for matrices to reflect the actual (higher) 15c CE limits rather than the original HP-15C limits as presently documented. We didn't do this initially since we didn't feel it had been well enough tested at the time, but now I think it is.

I don't have a comprehensive list of everything that would need to be changed, but below is a start. Please let me know of anything I missed or any corrections to my changes (I am not sure if my math is right so I'd appreciate someone verifying it):

Page 140, "64 matrix elements" becomes "96 matrix elements". In earlier testing I was told that "64 elements" was a hard limit, but the 15C CE lets you make and manipulate matrices even as large as 12x8, or even 96x1, so I think this should say "96 elements" also. (It does let you create a 9x9 matrix and attempt to calculate the inverse of it, but the results are incorrect -- that's why the manual says inversion and determinants can only be done on matrices up to 8x8.)

Page 148, "a maximum of 64 for all five matrices" becomes "a maximum of 96 for all five matrices".

Page 171, I am not certain about this, but I think "up to six columns if A is 2x2, or up to two columns if A is 3x3" becomes "up to ten columns if A is 2x2, up to five columns if A is 3x3, or up to two columns if A is 4x4" and then "or if A is 4x4, " would be removed. In the footnote, "If sufficient memory space" becomes "If all available memory space" and "33 64 00-0 or more" becomes "01 96 00-0".

I seem to recall there also being another difference being discovered between the 15C and 15c CE recently, or maybe it was another bug in the 15c CE firmware, but I can't remember now and I can't find it in the forum either. If that indeed is the case, it might be good to also update Appendix G or Appendix H with this new information too.

Is there anything else I've missed?

[naddy]

(10-31-2024 09:57 PM)Eric Rechlin Wrote:  I seem to recall there also being another difference being discovered between the 15C and 15c CE recently, or maybe it was another bug in the 15c CE firmware, but I can't remember now and I can't find it in the forum either.

J-F Garnier mentioned it here: On the genuine HP-15C, GSB label or f A..E displays the target step while the label key is held down. On the 15C LE/CE, the program execution starts immediately.

[Eric Rechlin]

(10-31-2024 10:33 PM)naddy Wrote:  J-F Garnier mentioned it here: On the genuine HP-15C, GSB label or f A..E displays the target step while the label key is held down. On the 15C LE/CE, the program execution starts immediately.

That's it, thank you! I propose adding the following to the bottom of page 269:

Holding Label Key after [GSB]

Pressing and holding a label designation after [GSB], or pressing and holding [A] through [E] in user mode, shows the target step on the HP-15C but runs the step immediately on the HP 15c CE.

[J-F Garnier]

(10-31-2024 11:15 PM)Eric Rechlin Wrote:  

(10-31-2024 10:33 PM)naddy Wrote:  J-F Garnier mentioned it here: On the genuine HP-15C, GSB label or f A..E displays the target step while the label key is held down. On the 15C LE/CE, the program execution starts immediately.

That's it, thank you! I propose adding the following to the bottom of page 269:

Holding Label Key after [GSB]

Pressing and holding a label designation after [GSB], or pressing and holding [A] through [E] in user mode, shows the target step on the HP-15C but runs the step immediately on the HP 15c CE.

I'm not sure it's really needed, for three reasons:
- For me, this difference is not an intentional improvement and rather belongs to the same category as the display quirks described in the Differences between the HP 15c CE and the original HP-15C thread, that are not documented in the 15c CE OH.
- Then, holding the [label] designation after [GSB] to see the step is not documented in the manual (AFAIK) - this is not a "feature".
- It may be corrected someday.

On the other hand, it would be good to add, in that p.270 about the old Self-Tests that they not only give no valid results but can corrupt memory.
E.g. starting from a cleared 15c CE:
- enter the program step 001 LBL A
- do the ON/x or ON/+ test that almost immediately produces Error 9,
- step 001 is changed to LBL 9.
I doubt this will be ever corrected.

J-F