A few questions about the CG50

I'm about to get a Casio Prizm FX-CG50 because I'm required to get a graphing calculator for calculus next year. This will be my first graphing calculator, and I have a few questions about it that I couldn't find easy answers to: 

Power: 
1. How's the battery life on Alkaline batteries? Casio claims 140 hours, but the backlit screen makes me skeptical of that claim. 4 AAA batteries only store about 6 watt-hours of energy. If the battery life is bad, I'll get Ni-MH batteries. 
2. If I install Ni-MH batteries, can I charge them by plugging the calculator into a 5V source, or will I need a separate charger? 
3. If I plug it into a 5V source, will the calculator run off of that instead of the batteries, even if it doesn't charge them? 
4. Can I extend the battery life on Alkaline by setting the calculator to think I'm using Ni-MH? I've seen digital cameras that would only drain Alkalines to 1.2V but would drain Ni-MH batteries to 1V. 
5. Is it possible to completely disable the backlight? 
6. If this calculator is overclockable, how much does overclocking impact the battery life? 
7. Is it practical to mod the calculator to use LiPo batteries? 

Software: 
1. Can I run software meant for the CG10/CG20 on a CG50? 
2. Can I run GNU/Linux on a CG50?  If not, is there a technical reason for why I cannot or is it because nobody bothered to port it?
3. Is it possible to brick the CG50 by messing with the OS too much, or does it have USB recovery in ROM? 
4. Am I required to use exam mode when taking AP tests or the SAT? 

5. I heard about this calculator having a service mode and a few other special boot modes. How do I get into those, and what can I do with them?

6. I've heard that TIs use cryptography to restrict the software that runs on them and Casios don't. How true is this?

Hardware: 
1. https://www.cemetech.net/tools/prizm has some specifications listed, but they are for the CG10/CG20. Are they accurate for the CG50 too? If not, is there another page for the CG50? If there isn't, I'd like to at least know the CPU, clock speed, screen resolution, and the amounts of RAM and Flash. 
2. There appears to be a serial port on the top that the manual said uses an SB-62 cable. I looked up that cable, and it looks like a normal 3.5mm audio cable. Can I use a normal 3.5mm cable? If not, what is preventing me from doing so?

Edited by linux-user, 09 June 2019 - 06:55 PM.

I have a CG20, bit thought about buying a CG50, so I collected information.

Both use the same processor SH4. The CG50 has a faster CPU takt, 118 MHz vs. 59 Mhz.

If one makes a software update of the CG20, it is nearly to the cg50 identical from software point of view. That means you can use CG20 programs at the CG50 and vice versa. The only remaining difference is that CG50 has a built in Python interpreter.

Battery life is not bad at least at the CG20. The calculator dimmes the display after some time of non use. This time can be set up. I think that you can use the calculator for a few weeks without charging in normal use.

For charging (if you use NiMH you have to open the battery case, remove the cells and load it in an external device. This has the advantage that you may simply put in spare cells.

The only disadvnatage of the cg50: After a while of non use the RAM is deleted.

Edited by piu58, 09 June 2019 - 09:32 AM.

Thanks. I'd rather have it be a single rechargeable battery that I can swap out when needed and charge using the USB port on the calculator, like how phones with removeable batteries worked, but I'm not going to buy an overpriced TI just for that. The main reason for getting a Casio is because I don't want to support a near monopoly and don't want to pay $130 for a TI-84CE or $170 for an nspire. At the time of writing, the CG50 is on sale for $78 on Amazon in the US. To me, that's still overpriced, but when compared to other graphing calculators it's a very good balance of features and cost. If I wasn't required to get a graphing calculator for school, I'd be willing to pay at most $20 for one. Also, based on what I read, casios are easier to use than TIs and are less restricted. Let's get back on topic.

So people do not need to read the entire thread, here's what's been answered:

Edited by linux-user, 09 June 2019 - 06:55 PM.

Dear linux-user, your black background posts are hard to read. Is there a reason for using that?

~

I have a few additional answers:

 > Can I extend the battery life on Alkaline by setting the calculator to think I'm using Ni-MH? 

No, that is for (more or less correct) guessing the battery state.

> 5. Is it possible to completely disable the backlight? 

No. That would not be of any sense. In contradiction to sthe 9860 series, the display is hard to read without backlight. I first started with the lowest level, but switched rather fast to level 3

> how much does overclocking impact the battery life?

The calculator needs power for calculation and power for the background light. The power for calculating increases with the clock speed.#

> There appears to be a serial port on the top that the manual said uses an SB-62 cable

There are two ports. A mini USB for connecting to a pc (the calculator acts like a memory stick) and a serial line for connecting calculators.

>  So basically, the CG50 is a faster nicer-looking (subjective) version of the CG10/20 with Python added?

Yes.

> isn't clearing RAM after shutdown expected behavior? Why is that a disadvantage?

Edited by piu58, 09 June 2019 - 03:11 PM.

I have a browser extension that makes every website dark theme. I guess it may be interfering with my posts too? I'll see if I can fix that.

Those are good answers. If something will take so long to calculate that I have to leave the calculator running for a few minutes and then come back to it, I would probably run the calculation on my laptop, but that clearing RAM thing is good to know about. Also, thanks for pointing out that the serial cable is for communicating with other calculators. I still have a few questions about it though.

> Is it just the prizms that have this serial port or do all casios have it?

I have wo fx-9860 which have this port. I think the 9850 and some older calculators two. Please keep in mind that this serial interface came first. Older calculators did not have an usb port so this was the only way to exchange data and programs.

I get it now. It used to be the only way to exchange programs and data, but they had to switch to USB because computers were no longer supporting plain serial natively, with the serial port just kept for compatibility.

@linux-user

Edited by sentaro21, 10 June 2019 - 12:59 PM.

That's awesome! If it runs off of USB, I think I'll use that to extend the battery life, and save the AAA batteries for situations where I don't have my USB power bank, such as the SAT. Was that intentional or just a byproduct of the USB port being connected directly to the 5V rail? Also, I hate restrictions on my hardware, so the lack of restrictions and the inability for the calculator to be bricked is good.

Also, thanks for mentioning ptune2. I'm going to need that.