25 replies to this topic

[Behnoud]

During the USB connection with the PC, the ClassPad 300 will be powered from the USB port of the PC. A physical connection with a running PC is enough to power the ClassPad. A Software connection via ClassPad Manager or other applications is not necessary.

[Kilburn]

We already know that Thanks anyway.

[Behnoud]

Can I use rechargeable battery?
It is just 3 weeks that I have bought my CP
but the batteries are dead.

[Kilburn]

Yes, rechargeable batteries work well, I always use them for my ClassPad

[Behnoud]

I wonder whether rechargeable battery get charged when an USB conection is available!

[PAP]

Can I use rechargeable battery?
It is just 3 weeks that I have bought my CP
but the batteries are dead.

First of all, welcome to the ClassPad "world" .
Using ClassPad heavily, alcaline batteries don't last a single week. My advice is: switch to rechargeable batteries as soon as possible. Btw, I bet that they cannot be recharged simply by connecting the ClassPad to a computer via a USB port.

[Kilburn]

Trouble is with rechargables is they are only 1.2 volts, whereas Ordinary Batteries are 1.5, so your display will be even duller and run ever so slightly slower than with normal batteries.

No, for my display, there is absolutely no change between 1.2 V and 1.5 V. And they last almost as long as alcaline batteries.

[MicroPro]

So, why the manual says don't use rechargable batteries? (I almost know nothing about electronics)

[2072]

Well maybe because they want you to buy normal batteries or because Nikel/Cadmium batteries have a very low internal resistance and their electronic is not suited for that...

I don't know why low internal resistance can be bad though... (it's maybe because a short-circuit with Ni/Cd is probably more dangerous...)

[Behnoud]

What is the meaning of Alkiline?
Can i use ordinary batteries instead of Alkiline ones?
They are too expensive with respect to others.

[Kilburn]

What is the meaning of Alkiline?

Alkaline. But normal batteries=Alkaline batteries! We were speaking about Ni-Cd batteries (=rechargeable batteries).

Personally, I use Ni-MH (or Ni-HM... how do you say that in English?) batteries, they are more practical.

[mortezahaydari]

Alkaline. But normal batteries=Alkaline batteries! We were speaking about Ni-Cd batteries (=rechargeable batteries).

Personally, I use Ni-MH (or Ni-HM... how do you say that in English?) batteries, they are more practical.

there is no matter if you use rechargeble ...but it will be empty soon ...it is not good for claaspad high use

there is no matter if you use rechargeble ...but it will be empty soon ...it is not good for claaspad high use

also... usb only works with classpad when there is some batteries in, doesnt it?

[Kilburn]

there is no matter if you use rechargeble ...but it will be empty soon

No I tried them, and they last as long as alkaline batteries.

[MicroPro]

OK. Thanks 2072, Behnoud, Kilburn and morteza.

[Behnoud]

Why Classpad doesn't have a backup baterrey?

[SoftCalc]

Why Classpad doesn't have a backup baterrey?

The ClassPad has something even better. All applications are designed to save all of there data when the power is turned off, and the ClassPad saves MCS to flash when you turn it off, so there isn't a need to a back up battery. You can take the batteries out for 10 years and still have all of your data.

[betoe]

Btw, I bet that they cannot be recharged simply by connecting the ClassPad to a computer via a USB port.

I think that its possible but it may take a lot of hours for recharge the batteries via USB port. A rechargeable battery needs a bit higher voltage for being recharged, and i think that the USB give to the classpad more than 2.4 V (normal batteries use an array for a 3V source to the classpad).

[Behnoud]

Some days after starting this topic, I used my CP conected to USB port to save CP's batteries. But last week my batteries went dead without any caution or warning! My CP battery indicator was full even! (three line was showed.) Does anyone khow why?

[Xtreme]

If your ClassPad was connected to the USB port is WAS on full power. If our batteries happen to go dead and you are plugged into the USB it won't tell you until you disconnect USB.

[The_AFX_Master]

Xtreme, That's not solve the problem.. read carefully

But last week my batteries went dead without any caution or warning! My CP battery indicator was full even! (three line was showed.) Does anyone khow why?

last week= 1 september

behnoud plugged his CP to the usb on:

Some days after starting this topic, I used my CP conected to USB port to save CP's batteries

this topic is from may 25

The problem is (i guess). Behnoud uses his calc plugged into USB some days.. then uses the calc normally, the battery indicator still full, some days more, the batteries dead without lo-batt message. Seems to be an O.S error that "believes" when is plugged to USB,that the batteries are new.. i guess

[Behnoud]

It is strange yet, isn't it?
I used a well-khown brand, the batterries were -n--g---r.(fill in the blanks )
I'll inform you the exact dates to decide accurately!

[Behnoud]

Is it posible that the USB connection has discharged my CP when it has been OFF?!
Or it has used a very low current from CP batteries?

[SoftCalc]

The ClassPad is always using electricity to keep the contents of RAM. You should set your ClassPad's power save mode so it can turn completely off when you don't use it for a long while.

When you turn your ClassPad off, it enters "very low" power mode and only powers RAM. When the ClassPad enters power save mode it backs up MCS (the ClassPad state including variables) to flash powers completely off. Then, when you turn your ClassPad back on again, it restores MCS and goes to the Launcher screen.

Really the only difference you'll notice is it will take just a bit longer to start and you'll be in the Launcher instead of the last application you were in, but it should have saved all the data from the last application.

The best tip on saving batteries is setting Power Save mode.

[SoftCalc]

I know some people are disappointed at the ClassPad's battery life, but they should realize that the ClassPad actually has a long battery life in comparison.

What some people don't understand is any other machine with a CPU running at a high clock rate and powering as much RAM as the ClassPad has a fraction of the battery life as the ClassPad. The HP-Xpander (which was canceled just before it was suppose to go into production) had rechargeable batteries and only lasted hours on a charge. The TI-NSpire has rechargeable batteries and only lasts for 3-4 hours! The last thing you'd ever want is to have your batteries die in the middle of a test!

The ClassPad has a power save mode that can be set so your ClassPad can be put into a drawer and you could come back a year later and it would turn on. When run continuously without turning it off it has a longer battery life than HP or TI.

That being said, if you don't set "Power Save" mode the batteries will not last as long as you might like. Casio could have forced "Power Save" mode all the time and not let the user turn this off. This would have eliminated any complaints about the battery life. Personally, I'm glad they at least give you the option.

[Behnoud]

Nowadays I'm glad too, because I have learnt how to save my batterries and how to reduce cost of replacing them.
Often I use CP Manager instead CP handheld or use My CP connected to USB.
So I'm satisfied now.
Thanks Soft Calc