Help in resetting an HP-50G

[Namir]

I received an HP-50G with custom surveying software. When I use a pin to reset the machine, it wakes up again with the custom software. the calculator came with a 2GB SD card and it seems dependent on that card. The custom software takes control over many keys (like SIN, COS, TAN, and so on).

I need help in reset the hP-50G to remove the custom surveying software.

Namir

[ndzied1]

There is some information here regarding reflashing the calculator.

https://www.educalc.net/1618486.page

[Namir]

On web page:

https://www.educalc.net/1618486.page

I tried the instructions and they did not work. I tried to delete files on the SD card, but the surveying app is so well intrenched in the calculator, it will not go away!

I think I will return the calculator

Namir

[rprosperi]

(09-26-2020 01:47 AM)Namir Wrote:  On web page:

https://www.educalc.net/1618486.page

How do I execute:

First go to (whiteshift) Files, select "2: FLASH" press OK. Now delete (purge) all files EXCEPT L226, L227 & L229 (periodic table and equation libraries). Then do the ON-F1-F6 reset and it should be in the "original" state.

I am asking because I tried the ROM update using an SD card. It did updated and I did a RESET, but teh surveying app came back full force!

Namir

Is the write protect switch set to ON (WP=true) on the SD Card? If so, then the filer (or anything else you try on the 50g) will not remove the files, because it's physically write-protected.

When you use the Filer as noted in the bold steps, do you get an error, and do the files seem to disappear from the listing?

[Joe Horn]

My guess is that the problem is not in the SD card. It's a takeover library of some kind in Port 1 or Port 2.

If you hold down the backspace key DURING a warmstart, it will prevent all the libraries from attaching themselves. This is a great way to keep a library in Port 1 or Port 2 from taking over your 50g, after which you can delete it using the FILER.

Method: With the calculator turned on, press and hold down the ON key, then tap and release the C (F3) key. Next, in very rapid succession, release the ON key and then immediately press and hold down the backspace key. Continue holding it down until the warmstart finishes. Press right-shift 2 (LIB) and look at the menu area. If you see no libraries listed, it was a success, so press left-shift APPS (FILES) and begin deleting what's in HOME and ports 0, 1, and 2. However, if you saw any libraries in the menu area, then you were not holding down the backspace key throughout the warmstart.

[Eric Rechlin]

What survey software is it?

If it's DC50 I wonder if that has a custom ROM for C code support so you might need to reflash it (Tim should know better). If it's something else, I'm really curious what it might be.

[Namir]

(09-26-2020 03:37 AM)Joe Horn Wrote:  My guess is that the problem is not in the SD card. It's a takeover library of some kind in Port 1 or Port 2.

If you hold down the backspace key DURING a warmstart, it will prevent all the libraries from attaching themselves. This is a great way to keep a library in Port 1 or Port 2 from taking over your 50g, after which you can delete it using the FILER.

Method: With the calculator turned on, press and hold down the ON key, then tap and release the C (F3) key. Next, in very rapid succession, release the ON key and then immediately press and hold down the backspace key. Continue holding it down until the warmstart finishes. Press right-shift 2 (LIB) and look at the menu area. If you see no libraries listed, it was a success, so press left-shift APPS (FILES) and begin deleting what's in HOME and ports 0, 1, and 2. However, if you saw any libraries in the menu area, then you were not holding down the backspace key throughout the warmstart.

Joe,

I had the calculator packed ready to return it. I decided to try your instructions. You sir are a WINNER!!!! Your instructions were spot on. I was able to get to the files of the Survey software and delete all the files. Now the 50G wakes up like a normal machine!!

Thanks thanks thanks ... Merci ... Danke ... Gratzi .. Shukran .... Teshekur!!!!

The whole thing makes sense to me now ... it took a Catholic priest to help perform exorcism of evil software that took over a machine!!!

Thanks you everyone for your feedback and suggestions.

Namir

[pinkman]

(09-26-2020 12:59 PM)Namir Wrote:  

(09-26-2020 03:37 AM)Joe Horn Wrote:  My guess is that the problem is not in the SD card. It's a takeover library of some kind in Port 1 or Port 2.

If you hold down the backspace key DURING a warmstart, it will prevent all the libraries from attaching themselves. This is a great way to keep a library in Port 1 or Port 2 from taking over your 50g, after which you can delete it using the FILER.

Method: [...]

[...]

The whole thing makes sense to me now ... it took a Catholic priest to help perform exorcism of evil software that took over a machine!!!

[...]

So we will unfortunately never know if it was Joe’s method or Namir’s priest that helped to get the 50G to normal life.
Next time anyone has to make the same, do both manipulation and prayer!

[Namir]

(09-26-2020 02:00 PM)pinkman Wrote:  

(09-26-2020 12:59 PM)Namir Wrote:  [...]

The whole thing makes sense to me now ... it took a Catholic priest to help perform exorcism of evil software that took over a machine!!!

[...]

So we will unfortunately never know if it was Joe’s method or Namir’s priest that helped to get the 50G to normal life.
Next time anyone has to make the same, do both manipulation and prayer!

Joe IS a Catholic priest!!! I believe he also holds a degree in mathematics.

Namir

[pinkman]

Best solution ever! My physics teacher was also a priest, but his prayers did not reach their goal I guess!

[acoto]

Part of my standard routine when getting a new HP-50 is to re-flash to standard image. Even if it came with in latest software version.

Also re-flashed a lot of times going back and forth between standard and NewRPL images. Not a single issue so far.

Good instructions here.
https://www.hpcalc.org/hp49/pc/rom/

2.15 firmware is my favorite.
https://www.hpcalc.org/details/7097

I use the files inside "2M FIX.zip", as they will wipe out everything, and truly revert Flash to factory conditions. It includes Equation library.

Try to recover Memory: "NO" after the upgrade is the perfect end for old data (and any weird behavior). If no dialog is presented "ON A F" key combination will send you to it.

Also remember to use standard SD card (not SDHC), formatted in FAT16. 1GB ( or smaller) card recommended.

iPhone SIM eject tool is great to push the HP50 reset button.

[Namir]

(09-26-2020 07:09 PM)acoto Wrote:  Part of my standard routine when getting a new HP-50 is to re-flash to standard image. Even if it came with in latest software version.

Also re-flashed a lot of times going back and forth between standard and NewRPL images. Not a single issue so far.

Good instructions here.
https://www.hpcalc.org/hp49/pc/rom/

2.15 firmware is my favorite.
https://www.hpcalc.org/details/7097

I use the files inside "2M FIX.zip", as they will wipe out everything, and truly revert Flash to factory conditions. It includes Equation library.

Try to recover Memory: "NO" after the upgrade is the perfect end for old data (and any weird behavior). If no dialog is presented "ON A F" key combination will send you to it.

Also remember to use standard SD card (not SDHC), formatted in FAT16. 1GB ( or smaller) card recommended.

iPhone SIM eject tool is great to push the HP50 reset button.

Yes I installed firmware version 2.15 on that HP-50G. I realized using the SD cards were very simple.

I am glad that Joe's instructions put an end to my nightmare! Admittedly, the developer(s) of the Surveying app were very good! They installed icon-based menus and maintained a series of folders on the SD card. The annoying thing was keys like SIN, COS, TAN, and so on were redefined!

Namir