50G resets after attempting Erase/Draw function with F'

[Skyblues]

Greetings,

I have run into a problem with my HP-50G that I was hoping someone may have a solution for. It happens on both my 50G and the emulator.

I am going through the HP-50g quick start guide; specifically the example on page 17.

Steps to reproduce:

1) Enter the equation 1/4 X^3 - X^2 + 1
2) Select Draw
3) Select Fcn -> F'
4) Select Cancel
5) Select Erase
6) Select Draw

The 50g resets by itself.
When I go back to where I enter an equation (LS hold / Y=) I am getting the following error:

Error:
No Current Equation

From this point, I am not able to return the Plotting functions/Equation Entry where I can Add an equation without getting that error.

On the emulator, I am able to reopen a saved *.e49 file.
On the real 50g, I have to restart using a paper clip and sometimes I have to do that numerous times.

Any suggestions on how to resolve this (besides don't do that again :-)

Thanks,
Jim

[Hlib]

I tried to reproduce this failure even several times intentionally interrupting power supply in operating time, but under normal conditions after that 50G did not reset itself and graphing plotting was correct.
In my calculator initially the strange behavior was also observed till I installed Rev 2.15.

[BartDB]

Hi,

I also cannot replroduce this error on a real 50g. I have firmware version 2.15 installed.

Check your firmware version by typing VERSION at the prompt. You will see something like:
2: "Version HP50-C
Revision #2.15"
1: "Copyright HP 2009"

If revision is below 2.15, I suggest you update and try again.
(see ROM 2.15 in HPCALC.ORG )

Best regards.

[Skyblues]

Both of my real 50gs and my emulator have the following version:

2: "Version HP50-C
Revision #2.15"
1: "Copyright HP 2009"

I don't understand why I am getting this error and others are not.
Should I try to update my 50g to ROM 2.15 in HPCALC.ORG anyway?

Both are 50gs relatively new and came with 2.15 already installed.

Jim

p.s.
When I press ON/F4 I get the following info:
Version: 04.02
Build: 0106

[Skyblues]

Well, this is a total mystery to me.

Regarding the emulator, I apparently had a corrupt *.e49 file which I believe is where the emulator stores its current information. I deleted the old *.e49 and created a new one. All seems well.

Regarding the real 50gs, I tried to reinstall ROM 2.15 but that didn't change anything. I had already had 2.15 installed so I just ended back where I started from.

I then tried ON/F1/F4 and that seemed to have worked.

Apparently, it's one of the Flags I have set. I'll have to go through them one by one and find the culprit.

I had the following set ... 03, 22, 27, 34, 40, 55, 56, 68, 97, 98, 105, 111, 116, 117, 119, 120.

Update: It was flag 55; No last args

Thanks,
Jim

[Hlib]

Skyblues wrote, post #1:

Quote: When I go back to where I enter an equation (LS hold / Y=) I am getting the following error:

Error:
No Current Equation

From this point, I am not able to return the Plotting functions/Equation Entry where I can Add an equation without getting that error.

Remaining in the current directory, we can return deleted function by pressing "choose" (F4) in "Y=" mode. Or, say Y1, disappeared from "var" in current directory?

Skyblues wrote, post #4:

Quote: Should I try to update my 50g to ROM 2.15 in HPCALC.ORG anyway?

Except mentioned in link (4950_215.bin), I also tested ROM-file 2MB_215f.bin (size 2 080 768 bytes) both in real HP-50G and in android simulator "go49gp_v1.0.6.apk" at the Chinese smartphone. No malfunction noticed. IMO, to be convinced that the calc is without defect, you should upgrade it using SD.
Setting system flag to "-55"=1 (i.e. No last args) does not cause error or reset at my devices. Formula for dF/dx changes to 1. So the calculator builds {Y1(X) 1.}, wich I can see in 2D/3D mode.
But I do not understand: what user flag "55" does in this case and where it works?

[Skyblues]

Since I have 2 50gs (actually 3, but one is still unopened) I decided to use one for an experiment.

I completely deleted EVERYTHING from the calculator (from all ports). I put 4950_215.bin on an SD card and ran the upgrade.

After the upgrade, the only thing I changed was Alg -> RPN.

I ran the scenario mentioned in this thread ... all was well. I then set Flag 55 and ran the scenario again. I got the original error.

I don't understand it either but I am still pretty new to this calculator. I have a 49 and 49G+ but haven't used them for a long time. I just bought the 50gs a few weeks ago and am re-familiarizing myself with the functionality which is very similar to my 49g+.

Part of the problem, I'm sure, is that I'm still experimenting and learning this thing. I've been going through some excellent youtube videos and the HP manuals.

I did an experiment with the clean install:

1) With Flag 55 off (unchecked), I run the scenario as described. All is well. After I cancel, I go to LS hold/F4 (2D/3D). What I see in Eq is ...
{ 1/4 x 3X^2 -2X Y1{X} }

2) With Flag 55 on (checked), I run the same scenario and get the reset. I can not return to (LS hold / Y=) without getting the error.
When I go to LS hold/F4 (2D/3D). What I see in Eq is ...
{ 'Y1{X}' External }

I'm pretty lost at this point.

Thanks for the suggestions,
Jim

[BartDB]

Hi,

OK, I can confirm that with flag -55 set (no last args) the calculator resets as per the description in the original post.

It seems that for re-plotting the F' function, last args is used by the calculator.

I don't know all the ins & outs either, so the best I can do is suggest to keep -55 clear unless you specifically require it set.

Best regards.


EDIT:

When you get that reset, go to VAR and PURGE the following:
'X'
'EQ'
'Y1'

Then you can enter Y= as normal, without having to paper-clip reset.

[Skyblues]

(08-04-2015 03:17 PM)BartDB Wrote:  Hi,

OK, I can confirm that with flag -55 set (no last args) the calculator resets as per the description in the original post.

It seems that for re-plotting the F' function, last args is used by the calculator.

I don't know all the ins & outs either, so the best I can do is suggest to keep -55 clear unless you specifically require it set.

Best regards.


EDIT:

When you get that reset, go to VAR and PURGE the following:
'X'
'EQ'
'Y1'

Then you can enter Y= as normal, without having to paper-clip reset.

BartDB,

Thank you for confirming, I appreciate it!

Jim

[Tim Wessman]

What a crap calculator...

[Skyblues]

(08-04-2015 11:22 PM)Tim Wessman Wrote:  What a crap calculator...

Haha, yeah, I should return this thing and stick with my Prime :-)

[BartDB]

(08-04-2015 11:22 PM)Tim Wessman Wrote:  What a crap calculator...

Not as crap as the 39gii and Prime.

[Gerald H]

(08-04-2015 11:22 PM)Tim Wessman Wrote:  What a crap calculator...

Odd...I guess the 50G is really on the way out.

Disclaimer:

Although I work for the government of Mogombo, all of the views & opinions I publish here have nothing whatsoever to do with me & are purely those of the Mogombo government channelled through my fingers.

[Skyblues]

(08-05-2015 05:34 AM)Gerald H Wrote:  

(08-04-2015 11:22 PM)Tim Wessman Wrote:  What a crap calculator...

Odd...I guess the 50G is really on the way out.

It may very well be. That's why I bought 3.

Disclaimer:

Even though the 50G isn't as cosmetically pleasing as my old 48GX, I actually like it better in many ways. I like my Prime as much as my 50G although they're very different.

I've been a working engineer for over 25 years but am still (and always be) a student of mathematics. I now do it just for fun.

I have lots of calculators but my 50G and Prime and my go to calcs. I still use my 30 year old 41CV (that still works perfectly) when the mood strikes but it pales in comparison to the 50G and Prime.