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Comment by freehunter | Hacker News Reader

This really should be the next thing the RPi team tackles, IMO. It's nice we have this great cheap computer, but trying to find a screen to plug into it is terrible. A computer monitor or TV is fine, but both of them draw too much power and are far too big and stationary. And have you seen the prices of small HDMI screens? I can buy a 8" Windows tablet, full PC mind you, for the price of a single 5" HDMI screen.

Far too often I find myself saying "it shouldn't be this hard". Surely there exists a market for an adapter to plug an easily available iPhone screen into an RPi?

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What I'd like to see is a calculator shell that you could pop the RPi into, including physical buttons, lcd screen, battery and charger. My thinking -- most high schools require a graphing calculator, such as the TI 89 or similar, which is around $100 or so. Imagine if for that $100 you get something that can act as the same calculator, but morphs into a full computer when plugging in a keyboard/monitor? It may end up getting a lot more kids into programming that way.

And then you have to buy a graphing calculator anyway because no high school teacher / university professor will let you take tests with it.

Hell, I'm surprised some of my teachers let me use a graphing calculator one tests that didn't require them. They're already powerful enough to easily cheat with.

Because of cheating? How can you use the Raspberry Pi (in a calculator shell) to cheat, in such a way that you can't use a ti-89 to cheat? Most cheating will be by either storing crib notes on the device (which won't do you any good in math if you don't understand the concepts), or by running a program to solve a problem for you, both of which the ti-89 is more than capable of doing -- that is its whole purpose, is to run math programs.

The ideal situation would be where the RPi foundation uses its existing clout to get a PiCalc accepted as a standard calculator in school.

Wifi?

During my high school exams, every calculator would get reset by a teacher/supervisor beforehand. Harder to do with such a device.

This was still trivial to get around on calculators: on a TI 83/84 you could simply archive any programs you wanted to survive a memory wipe, then un-archive them after the wipe. This trick was widely employed by students in my high school who stored notes/equations by using programs as generic text files.

Standardized test calculator rules in this country are not governed by reason.

For instance, a TI-89 is allowed on the SATs, but a TI-92 is not. Basically the same calculator, except the TI-92 has a qwerty keyboard. How would a tiny little qwerty keyboard actually give you an advantage on a test like the SAT? Who the hell knows. Remember 10 or so years ago when teenagers were all typing on telephone keypads?

On the other hand, the advantage of a TI-89 (with a CAS) over a TI-83+ (without one) is fairly extreme.

(Also, anyone who bothers to google it can trivially get around the reset key combos for at least 83+ line: http://brandonw.net/calculators/fake/ Somebody who takes the time to program their calculator for cheating on a test can do this)

I don't know if it's fair to say that the rules aren't governed by reason. You're thinking only of the capabilities of the calculator, but there are other potential reasons that are valid. It could be a simple matter of wanting to make it easy for testing staff to identify acceptable calculators by making the list of acceptable calculators very small.

The TI-92 with its keyboard was banned not because it would help the test taker, but because of a worry that the full keyboard would enable copying the test to send to someone in a later timezone.

I am skeptical that it would be of any help, particularly since the calculator is only allowed to be out during the math sections, not during the language/written sections.

With the 89's input history, you could effectively record the mathematics section merely by running it all through your calculator and then extracting the history after the fact.

There are two camps on why teachers might disallow calculator:

1) fear of cheating

2) because the teachers want you to do the calculation

When I took my Calc and my engineering courses, my teachers would not allow calculators. They would make sure the numbers are nice, not some crazy number or pi to calculate with. Volts, current, all those numbers are so nice we can do on the paper. I like that because it means the teacher actually put effort to ensure the numbers are not just random, they mean something to the teacher who created the exam (even though they might just change the number next semester).

its called your phone

This can't happen soon enough for me:

https://www.indiegogo.com/projects/pi-top-a-raspberry-pi-lap...

.. but then, this is also pretty usable for the same purpose:

http://www.raspberrypi.org/forums/viewtopic.php?t=6747

You can buy this today: http://www.lilliputuk.com/monitors/hdmi/668gl/

Which costs $270 to be shipped to my house. That 10x what the Pi itself costs.

That's a pro video monitor - considerable overkill for a Pi.

I'm also still waiting for this one: http://techcrunch.com/2014/10/21/pi-pads/ It looks like the official site is down atm but they mention an introduction in 2014 in their FAQ. It's a 640x480(!), 7" touchscreen.

You can pick up a 7" touchscreen (1280x800) that works with a DPI display like this blog post mentioned right here: https://www.adafruit.com/products/2354

The link you posted gives a resolution of 800x480.

That would be great. If you're starting from scratch, the display is likely to be the most expensive piece to get a pi running. Sure, you can plug it into a TV like the old days, but who has a TV that small anymore?

And being able to run the Pi and the screen from a portable USB battery pack would be nice. It would help hobbyist projects (who wants a robot plugged into a wall?), it would help kids using them to learn (take your whole setup wherever you go), and it would help people in developing areas of the world (where there might not be an abundance of cheaply available and reliable power).

If you can tolerate PAL: http://www.dx.com/p/4-3-lcd-monitor-for-visual-reversing-veh...

If you want a screen, just buy a $50 tablet. The Raspberry Pi is basically a tablet computer chip minus the tablet.

+ GPIO pins + FOSS software + Maker community, which make all the difference.

I see your point, but that's far less fun! :)

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