Removing HP 50g battery warning box?

[Carsen]

Hello!

I am Carsen and I am new to the HP Museum forums and relatively new to HP Calculators.

I have been working with my new HP 50g for almost 3 months now and I LOVE RPN. And despite its well known steep learning curve, I have progressed well in learning how to operate it. However, I have a question. Is it at all possible to REMOVE the battery warning box from appearing everytime I power on the unit? Or is it just a mere fantasy of mine? I am really annoyed of having the low battery textbox appearing every time, especially since I have squeezed 19 more days of regular use at school with low batteries before.

I would much rather the HP 50g just illuminate its battery announcer at the top of the screen to warn me of low batteries. Like my father's HP-15c (except his battery announcer is on the bottom left of the screen).

[Gilles59]

(01-02-2017 04:58 AM)Carsen Wrote:  Hello!
Is it at all possible to REMOVE the battery warning box from appearing everytime I power on the unit?

Hello Carsen
yes it is possible : just change the batteries ...

Happy new year !
Gilles

[Vtile]

Hello, get a 4 AAA NiMh batteries (ie. Varta 1000mAh or Eneloops etc. good quality ones) and keep 4 alkaline AAAs as a backup at the bottom of your backpack, then you do not need to look at those battery warnings and will save you a some money in the longer run.

Just take well known quality brand and ones that state that they are "Ready to use" or "Low self-discharge" so they work almost as normal alkaline cells. Only drawback is that you can not squeese a weeks of use after battery warning as they drop out much quicker than alkalines. (Something I should test actually since I now have set of right sized "test subjects" in my disposal.). Obvius is obvious you need a (suitable) charger for them also.

[Carsen]

(01-02-2017 09:27 AM)Gilles59 Wrote:  

(01-02-2017 04:58 AM)Carsen Wrote:  Hello!
Is it at all possible to REMOVE the battery warning box from appearing everytime I power on the unit?

Hello Carsen
yes it is possible : just change the batteries ...

Happy new year !
Gilles

Thanks for your time and response Gilles59! Yes, I am aware that changing the batteries would get rid of the battery warning box. It says to do so in the HP 50g User's guide and it's also the natural thing to do. But what I am aiming for is to remove the battery warning box from repeatedly showing up when powering it on every time - even with low batteries. The only method I want my HP 50g to alert me of low batteries is the battery announcer at the top of the screen - regardless of battery level. I know I am being a bit unreasonable trying to ask for a solution to this. It seems impossible but I was willing to give it a shot and hope for the best.

Quote:
Vtile

Hello, get a 4 AAA NiMh batteries (ie. Varta 1000mAh or Eneloops etc. good quality ones) and keep 4 alkaline AAAs as a backup at the bottom of your backpack, then you do not need to look at those battery warnings and will save you a some money in the longer run. Smile

Just take well known quality brand and ones that state that they are "Ready to use" or "Low self-discharge" so they work almost as normal alkaline cells. Only drawback is that you can not squeese a weeks of use after battery warning as they drop out much quicker than alkalines. (Something I should test actually since I now have set of right sized "test subjects" in my disposal.). Obvius is obvious you need a (suitable) charger for them also.

Thanks Vtile for your response! So far, the solution you offered is an appealing one because I will be flying through batteries next semester due to calculus and physics class. Plus, when the NiMh batteries hit the low battery warning, all I have to do is recharge them and I won't get bothered with the low battery warning box. Although I will wait for more ideas before deciding put money into NiMh batteries and a charger.

[Vtile]

Here is some data of Alkalines vs. modern NiMH. It is not scientifically accurate and even a bit dodgy in technical viewpoint, but the measuring setup is 1:1 comparable to each case. The constant current discharging is made with custom linear circuit, found ie. on Maxim Integrated application notes (IIRC) in other words a transistor and a operational amplifier as a controller.

Interesting is the Duracel Ultra Power, if you put the minimum voltage to 0.9 volts in is on the lower end middle of spectrum (this is not full dataset for clarity).

HP50g current draw in general is lower and not constant which makes difference, but I'm not too eager to test low current discharges (time and my test setup draw 100W minimum ). If I recall correctly HP50g have battery warning level at 1.1 Volts per battery (again readed somewhere IIRC).

Comparison between alkalines and one NiMH. (3600 s = 1 hour) Y-axis is voltage (0,5 to 1,7 volts)
   

Comparison between AAA NiMH (different cells unfortunately, and the one with smaller discharge current were loaded about two weeks earlier and a bit poor measure start (thats why there isn't as high starting voltage)), Interestingly the discharge shape is almost the same while with lower discharge it last considerably longer. ...Maybe I run one with 100 mA which starts to be close to HP50g peaks (65mA reported with regular "heavy" - I assume - calculations.). It were suprise to me today, that NiMH last in this my little test so much longer than those best alkalines (I see it in both 320mA (not shown here) and 500mA datasets (partially at above picture)).

   

Edit.. 2xsame picture, now it is correct.

[mark4flies]

I have used re-chargeable AA and AAA batteries for many years. They cost more to begin with but the current battery tech lasts a long time.

[TravisE]

I don't know of a way to disable the warning (other than hacking the system ROM or perhaps with SysRPL/ASM code). Going with rechargeable batteries isn't a bad investment if you go through more than a few sets per year; I did this many years ago and haven't looked back.

I recommend the low-self-discharge or “pre-charged” type, as you can charge them up and leave them ready to use on the shelf, and they will self-drain very little even if they sit unused for several months. There doesn't appear to be any real advantage in using conventional NiMH cells of the same capacity anymore; low-self-discharge seems to be the way to go whenever possible. A lot of people seem to swear by the Eneloop brand, and these are what I use. They seem to last roughly the same length of time on a full charge as ordinary alkaline, though as others state, there tends to be less “grace time” for the low-battery warning. However, the 50g still gives a reasonable amount of warning time for most NiMH, in my experience (normally enough for a least a hour or two more of usage). Usually I use the batteries until the warning first appears, then I'll swap them out for a freshly-charged set at the first convenient opportunity.

I tend to stay away from rechargeable cells claiming extremely high capacities (more than about 2400 mAh for AA or 800 mAh for AAA), as they seem to have service life and/or self-discharge characteristics compromised in return for only a modest increase in per-charge runtime.

Of course, these AA/AAA rechargeable batteries are useful in almost any other device using that type, so if you have other such devices, you can save more money there. Usually they work fine. I've come across a few occasional devices that are very picky about voltage and don't work well below 1.5 volts, meaning NiMH/NiCd cells don't work well. These devices are very poorly engineered, though, because even a brand-new alkaline drops well below 1.5 volts pretty quickly, which means a lot of available energy goes to waste with such devices. Properly-designed devices are supposed to operate normally as low as around 1.0 volt per cell, and the 50g does this well.

[Carsen]

(01-08-2017 02:15 AM)TravisE Wrote:  I don't know of a way to disable the warning (other than hacking the system ROM or perhaps with SysRPL/ASM code).

YES! This is the question that I am trying to get solved. This is the fantasy that I am trying to breathe to life! I would like to disable the low battery warning box and leave the top low battery announcer as the ONLY way to alert me if my batteries are low.

I like the NiMH battery ideas and there is certainly a lot of VALUABLE information that you all have given me but I still would like to accomplish this "fantasy" of mine somehow. Please don't think of me as being naive but rather think of me being hopeful.

Any more ideas, suggestions, or approaches to solving the HP 50g fantasy of mine?

Or, how do all of you brilliant people fuel your HP 50g?

[Software49g]

Hello,

(01-08-2017 02:15 AM)TravisE Wrote:  I don't know of a way to disable the warning (other than hacking the system ROM or perhaps with SysRPL/ASM code).

the only way to remove the "HP 50g battery warning box" is by modifying the internal TurnOff code, as this is the place where the batteries are checked.
As you can not modify this code, it is most likely impossible from the outside.

A partial solution would be to use a customized/modified SOL.
For this you need to take control over the keyboard via an exchanged SOL so that you can control [RS] [OFF] (and the other shifted possibilities to turn off the machine) and you need to take control over the timeout routine which turns off the machine. The timeout routine is also called from the SOL.

Note however, that this has no effect on the programmable command OFF or other areas in the ROM that call the TurnOff code (e.g. Kermit server, POLs that call TurnOff) as in this cases you won’t have control over it.

HTH,
Andreas

[RMollov]

(01-02-2017 04:58 AM)Carsen Wrote:  I have been working with my new HP 50g for almost 3 months now and I LOVE RPN.

How about RPL? Love it too?

[Carsen]

(01-08-2017 03:53 PM)RMollov Wrote:  

(01-02-2017 04:58 AM)Carsen Wrote:  I have been working with my new HP 50g for almost 3 months now and I LOVE RPN.

How about RPL? Love it too?

Yes! Although there are slight differences between RPN and RPL, I love each of them equally! And I don't find it hard at all to switch between the two of them. I transfer from using a HP-15c still owned by my father and my own HP 50g daily.

[Carsen]

(01-08-2017 01:31 PM)Software49g Wrote:  Hello,

(01-08-2017 02:15 AM)TravisE Wrote:  I don't know of a way to disable the warning (other than hacking the system ROM or perhaps with SysRPL/ASM code).

the only way to remove the "HP 50g battery warning box" is by modifying the internal TurnOff code, as this is the place where the batteries are checked.
As you can not modify this code, it is most likely impossible from the outside.

A partial solution would be to use a customized/modified SOL.
For this you need to take control over the keyboard via an exchanged SOL so that you can control [RS] [OFF] (and the other shifted possibilities to turn off the machine) and you need to take control over the timeout routine which turns off the machine. The timeout routine is also called from the SOL.

Note however, that this has no effect on the programmable command OFF or other areas in the ROM that call the TurnOff code (e.g. Kermit server, POLs that call TurnOff) as in this cases you won’t have control over it.

HTH,
Andreas

Okay. I have two questions. What do you mean by saying "it is most likely impossible from the outside"? And what is a SOL?

Please pardon my ignorance.

[Software49g]

Hello,

(01-10-2017 11:55 AM)Carsen Wrote:  Okay. I have two questions. What do you mean by saying "it is most likely impossible from the outside"? And what is a SOL?

Q1:
That simply means, that you can not fix it via software - the only way to not allow a battery warning box is by exchanging/modifying the appropriate code in flash rom.
Either by writing your own ROM or by patching the flash memory.

Q2:
When the 50g boots the System Outer Loop is installed in RAM. As the SOL resides in RAM you can exchange it with another one - but there can only be one SOL present.
The SOL is the lowest loop and therefore the lowest control instance of the 50g.
Other loops, like a POL (Parameterized Outer Loop) can be started from there, allowing different tasks (like the MODE screen, the Filer, etc.) to be done and returning to the SOL afterwards.

A typical SOL looks like this:
::
BEGIN <- mark address for AGAIN
AtUserStack <- mark current stack
SysMenuCheck <- check menuline (DA3)
SysDisplay <- check display (DA1, DA2a/DA2b )
GetKeyOb <- loop that waits for a key press (also handles the cursor, handles exceptions like timeout, alarm, etc.)
ERRSET <- set up an error trap
DoKeyOb <- process key and if no error then continue at [AGAIN]
ERRTRAP <- in case of an error
SysErrorTrap <- do the error trap code and then continue
[AGAIN] <- jump to AtUserStack
;

HTH,
Andreas