HP-15C CE woes: 1 bug, 2 limitations, 3 questions

[Thomas Radtke]

(08-09-2023 02:19 PM)J-F Garnier Wrote:  For me, the main limitation of the 15c is the fact that program steps are still recorded as keycodes.
This seems to me absolutely archaic in 2023. I really would welcome a 15c with clear instructions à la 41C: LbL, STO, RCL, ...
It would not break any compatibility and would give a tremendous comfort for programming.
The 41C series introduced this innovative feature in 1979, unfortunately the 1981 Voyager series went back to keycodes.
It was a big step backward at the time, and I remember that I initially didn't like this series for this very reason.

I presume an emulator would be able to translate the screen content to mnemonics with little effort. Was there a reason no one did this for the various emulators?

[Didier Lachieze]

(08-11-2023 06:25 AM)Thomas Radtke Wrote:  I presume an emulator would be able to translate the screen content to mnemonics with little effort. Was there a reason no one did this for the various emulators?

It has been done at least for the Android goxx emulators (go15c, go25c, go34c …).
Of course it cannot be done on the 15C CE 7-segment display but SwissMicros could have done it on the DM15L and it’s dot-matrix display.

[ThomasF]

(08-11-2023 06:25 AM)Thomas Radtke Wrote:  

(08-09-2023 02:19 PM)J-F Garnier Wrote:  For me, the main limitation of the 15c is the fact that program steps are still recorded as keycodes.
This seems to me absolutely archaic in 2023. I really would welcome a 15c with clear instructions à la 41C: LbL, STO, RCL, ...
It would not break any compatibility and would give a tremendous comfort for programming.
The 41C series introduced this innovative feature in 1979, unfortunately the 1981 Voyager series went back to keycodes.
It was a big step backward at the time, and I remember that I initially didn't like this series for this very reason.

I presume an emulator would be able to translate the screen content to mnemonics with little effort. Was there a reason no one did this for the various emulators?

The emulator for Android, eg go15c and go16c have this option.
Here you can select if keycodes or mnemonics should be used.
   

Cheers,
Thomas

[Thomas Radtke]

(08-11-2023 06:52 AM)Didier Lachieze Wrote:  It has been done at least for the Android goxx emulators (go15c, go25c, go34c …).
Of course it cannot be done on the 15C CE 7-segment display but SwissMicros could have done it on the DM15L and it’s dot-matrix display.

Ah ok, I've only had the small DM15. Yes, very difficult to do on a 7-segment display, but a lot of codes would work straight like RCL, STO, LBL, GTO, GSB and many others.

[Bernd Grubert]

(08-09-2023 02:19 PM)J-F Garnier Wrote:  For me, the main limitation of the 15c is the fact that program steps are still recorded as keycodes.
This seems to me absolutely archaic in 2023. I really would welcome a 15c with clear instructions à la 41C: LbL, STO, RCL, ...
It would not break any compatibility and would give a tremendous comfort for programming.
The 41C series introduced this innovative feature in 1979, unfortunately the 1981 Voyager series went back to keycodes.
It was a big step backward at the time, and I remember that I initially didn't like this series for this very reason.

J-F

I agree with J-F. This is a big drawback of the HP-15C. It make checking and editing source code a pain. Berhard Emese (aka PANAMATIK) has implemented in his excellent act-replacement boards a character display that works with the 7-segment display of the Woodstock and Spice models. It can be used to show the mnemonics in PRGM-mode instead of the keycode. Some characters look bit strange on first sight but after a short time you get used to it. This feature is a huge improvement. With Bernhard's consent it might be possible to implement the character display in the current hardware of Collectors Edition, too.

Bernd

[J-F Garnier]

(08-11-2023 08:10 AM)Thomas Radtke Wrote:  

(08-11-2023 06:52 AM)Didier Lachieze Wrote:  It has been done at least for the Android goxx emulators (go15c, go25c, go34c …).
Of course it cannot be done on the 15C CE 7-segment display but SwissMicros could have done it on the DM15L and it’s dot-matrix display.

Ah ok, I've only had the small DM15. Yes, very difficult to do on a 7-segment display, but a lot of codes would work straight like RCL, STO, LBL, GTO, GSB and many others.

Yes, many can be obtained with 7 segments only, but not the very commun + , ÷ , x and the many functions involving x: x<>y, e^x, y^x.

A 41C-type 14-segment LCD in needed, or better a 32S-type dot-matrix LCD.
So definitively out of the scope of the 15c CE project, but could be done on the DM15L.

BTW, the (excellent) little PX15C emulator made by agarza displays the symbolic function name on top (!) of the regular keycodes.

J-F

[EdS2]

(08-09-2023 04:29 PM)ThomasF Wrote:  Maybe this little program can show the correct decimal value:

Splendid!

(Jut a thought: as an engineer dealing with computer arithmetic, decoding, and the like, I would have used HEX and BIN as such. The relationship with decimal would not have come up. But I see, as a number theorist or mathematician, one might be interested in 64bit integers and want to work in decimal.)

[ThomasF]

(08-11-2023 02:20 PM)EdS2 Wrote:  

(08-09-2023 04:29 PM)ThomasF Wrote:  Maybe this little program can show the correct decimal value:

Splendid!

(Jut a thought: as an engineer dealing with computer arithmetic, decoding, and the like, I would have used HEX and BIN as such. The relationship with decimal would not have come up. But I see, as a number theorist or mathematician, one might be interested in 64bit integers and want to work in decimal.)

Haha, yes indeed, I spend most of my time in HEX- or BIN-mode!
OCT mostly when doing MCode reading or programming.
DEC happens now and then, but having a machine where I can't trust the values feels very awkward, so I wrote this little program to be able to use DEC as well.

It's a pity, but I will probably rely on my HP16C rather then using the 16CE-mode. It could have been a real hit, but since memory is cleared every time you change mode ... so maybe not.

(Keeping my fingers crossed that we one day might be able to re-flash (a NOMAS way) the devices to correct the "bug".)

Cheers,
Thomas

[Gilles]

(08-09-2023 02:19 PM)J-F Garnier Wrote:  (...)
For me, the main limitation of the 15c is the fact that program steps are still recorded as keycodes.
This seems to me absolutely archaic in 2023. I really would welcome a 15c with clear instructions à la 41C: LbL, STO, RCL, ...
It would not break any compatibility and would give a tremendous comfort for programming.
The 41C series introduced this innovative feature in 1979, unfortunately the 1981 Voyager series went back to keycodes.
It was a big step backward at the time, and I remember that I initially didn't like this series for this very reason.

J-F

I totally agree. A great example of what even a very basic ALPHA mode adds is what CASIO did between the FX-502P and 602P. It's exactly the same programming system but with the instructions in clear and very easily modifiable programs. Add to that a very simple possibility of displaying characters like "Enter X" HLT Min01, or "X=AR01" to display the contents of memory 01 and that changes everything. After the HP50 the CASIO 602P remains my favorite calculator, but I have become unable to use the 502P. ;D.
Too bad HP didn't do it at the time but I guess it was not to compete with the 41C

[carey]

(08-09-2023 02:19 PM)J-F Garnier Wrote:  For me, the main limitation of the 15c is the fact that program steps are still recorded as keycodes.
This seems to me absolutely archaic in 2023. I really would welcome a 15c with clear instructions à la 41C: LbL, STO, RCL, ...
It would not break any compatibility and would give a tremendous comfort for programming.
The 41C series introduced this innovative feature in 1979, unfortunately the 1981 Voyager series went back to keycodes.
It was a big step backward at the time, and I remember that I initially didn't like this series for this very reason.

There's no disagreement that mnemonic instructions, as in the 41C series, facilitate coding and debugging vs. key location instructions used in the 15c, but there's an interesting point that's easy to overlook about the 15c. The fact that key locations can even be used to program the 15c is remarkable and due to the fact that all its commands and functions are on the keyboard! Hence, it's a moot comparison to the 41C series since key locations wouldn't uniquely map to instructions with so many functions and commands in the catalog and not on the keyboard.

Was the decision to use key location instructions really a step backwards in the 15c? In one sense, yes. But in another sense, if one views the 15c as a personal tool, like a hammer, that becomes an unconscious extension of one's hand, the 15c keyboard is so ingrained in the minds of heavy 15c users that designating instructions by key location provides the brain (which is a master cartographer in forming and using mental maps) with the same information that would, on another calculator, require mnemonic instructions. The continued popularity of the 15c forty years after initial release suggests this mental mapping of key locations to programming instructions becomes second nature (and can be fun!).

[Steve Simpkin]

(08-13-2023 09:36 PM)carey Wrote:  

(08-09-2023 02:19 PM)J-F Garnier Wrote:  For me, the main limitation of the 15c is the fact that program steps are still recorded as keycodes.
This seems to me absolutely archaic in 2023. I really would welcome a 15c with clear instructions à la 41C: LbL, STO, RCL, ...
It would not break any compatibility and would give a tremendous comfort for programming.
The 41C series introduced this innovative feature in 1979, unfortunately the 1981 Voyager series went back to keycodes.
It was a big step backward at the time, and I remember that I initially didn't like this series for this very reason.

There's no argument that mnemonic instructions, as in the 41C series, facilitate coding and debugging vs. key location instructions used in the 15c, but there's an interesting point that's easy to overlook about the 15c. The fact that key locations can even be used to program the 15c is remarkable and due to the fact that all its commands and functions are on the keyboard! Thus, in a sense, it's a moot comparison to the 41C series since key location wouldn't uniquely map to instructions with so many functions and commands not on the keyboard but in the catalog.

So was using key location instructions really a step backwards in the 15c? In one sense, yes. But in another sense, if one views the 15c as a personal tool, like a hammer, that becomes an unconscious extension of one's hand, the 15c keyboard is so ingrained in the minds of heavy 15c users that designating instructions by key location provides the brain (which is a master cartographer in forming and using mental maps) with the same information that would, on another calculator, require mnemonic instructions. The continued popularity of the 15c forty years after initial release suggests this mental mapping of key locations to programming instructions becomes second nature (and can be fun!).

I don't see the keycode display used on the Voyager series as so much of a step backwards since the mid-range Voyager series was not intended to compete with or follow-up on the HP-41C series. By 1980 HP had a serious problem. There were now many other brands of scientific calculators available from other manufactures that featured LCD displays and long battery life. The HP Spice models, while excellent calculators, were looking a bit long in the tooth with their LED displays and short battery life. The Pioneer series was in the planning stage but were going to take years to develop. HP needed a short term mid-range solution to compete with the other manufacture's LCD models. This is where the Voyager series came in. If you look at the design goals of the Voyagers, they needed to be priced reasonably to compete in this market. They could still command premium prices since they had features that set them apart from the competition (programmability, high quality, reliable operation, long life, etc.) but they could not charge HP-41C type prices. That meant, in part, 7-segment LCDs so no alpha instruction display. All-in-all, I think they did very well for a "short-term" solution.

[Divasson]

   

They say an image is worth 1000 words.

[Didier Lachieze]

Great ! Is there a way to get the updated firmware? (I have the cable shown on the picture)

[Divasson]

Is not the same cable - it needs to be modified (the 15c CE uses USB protocol and the pin connections are different from the original. There was a description of the two different pin arrangements in a past thread - possibly when discussing HP12c versions). The mod is "destructive": you will not be able to use the cable with the 15c LE anymore.

[Voldemar]

Is there already a firmware where the 16c mode errors are fixed?

[stoiclunchbox]

(10-14-2023 11:55 AM)Divasson Wrote:  They say an image is worth 1000 words.

This is what I have been waiting/hoping for!

I too would like to know where we might be able to get this firmware.
I should be able to make an appropriate cable with some things I have lying around and the pinouts from the forum.

If we are able to update the 15c CE firmware to resolve the DEC mode bug, will the overlays become available to people who wish to update their 15c CEs and purchase them?

[Didier Lachieze]

(10-14-2023 12:20 PM)Divasson Wrote:  Is not the same cable - it needs to be modified (the 15c CE uses USB protocol and the pin connections are different from the original. There was a description of the two different pin arrangements in a past thread - possibly when discussing HP12c versions). The mod is "destructive": you will not be able to use the cable with the 15c LE anymore.

I forgot this important point, I was lured by the connector on the picture.

[Steve Simpkin]

(10-14-2023 12:20 PM)Divasson Wrote:  Is not the same cable - it needs to be modified (the 15c CE uses USB protocol and the pin connections are different from the original. There was a description of the two different pin arrangements in a past thread - possibly when discussing HP12c versions). The mod is "destructive": you will not be able to use the cable with the 15c LE anymore.

I think post #24 in the following thread is what you are referring to. It describes the pinout of the 2x3 connector used in the 2015 and newer HP-12C compared to the older serial pinout used on earlier models. I suspect this is still relevant for the HP-15 CE.
https://www.hpmuseum.org/forum/thread-51...l#pid46057



Further along in post #35 of the same thread, Tim Wessman describes an unfortunate "oversight" in the hardware design of the 2015 and newer HP-12C that would permit a standard surface mount Micro USB connector to be used on the HP-12C. I hope it is still relevant to the HP-15 CE.
https://www.hpmuseum.org/forum/thread-51...l#pid46108

"However, due to a serious oversight in our electrical design, someone accidentally left a surface mount on an extreme edge of the boards that happens to perfectly fit a surface mount micro USB. These pads were also accidentally connected to the internal USB circuitry of the chip. Should you accidentally cut a small hole in the plastic case on the edge that accidentally lines up with the accidental surface mount, you might be able to accidentally use USB to do reprogramming. Happy accidents! (obviously voids your warranty)"

In post #41, Katie Wasserman has some photos showing the above details.
https://www.hpmuseum.org/forum/thread-51...l#pid46221

https://wass.net/images/IMG_1057.JPG

[ebs]

Hi, this is my first message, I'm a new RPN user, I discovered RPN about 5 year ago and recently I have acquired some HP calculators including the HP-15C CE.

Davisson, glad to hear there is a fix for HP-16C emulation bug, this is based on original firmware? or it's a new firmware with its own emulator?

This also opens the door to have fixed the key bounces bug (e.g. when key 6 is pressed one time but two presses are registered "66"), it only happens perhaps 1/50 but when it does it's really annoying.

Please keep us informed when the firmware rom is available.

[J-F Garnier]

(08-09-2023 10:42 AM)ThomasF Wrote:  Another bug/limitation/difference between 16CE and the original 16C is the momentarily showing of other base modes.

If eg in DEC-mode, you can press 'f' then HEX to temporarily see the value in Hex-mode.
On the original the value is shown as long as the key is pressed, but the 16CE only shows the value for some seconds, independent on how long you press the key.

(08-09-2023 08:11 PM)ThomasF Wrote:  f MEM and f STATUS works as the mode, ie in the original 16C shows status as long as the key is pressed, but on the CE only for some seconds.

Also note this annoying effect:
If a key is pressed during the SHOW BASE, MEM or STATUS display, then the 16c emulator locks at the end of the temporary display (non-operating keyboard), apparently in a high power state.
If you don't notice it quickly, it can deplete the batteries in a short time.
Only solution: press the RESET button in the battery compartment.

J-F