Ask Slashdot: Why Buy a Raspberry Pi When I Have a Perfectly Good Cellphone?

scorp1us writes "I've been looking into getting a Raspberry Pi, but I end up needing a case, a display, and some way to power it, and wanting some degree of portability. It seems to me that even the most outdated cellphone has far superior features (screen, touch screen, Wifi, 3g/4g camera(s), battery etc) in a much better form factor. The only thing that is missing are the digital/analog in/out pins. So why not flip it around and make a USB or bluetooth peripheral board with just the pins? I've been looking for this and can't find any, but does anyone know of any in the corners of the internet? I don't care what phone platform."

Depends on use-case

[StealthHunter]

If your use-case is "leave attached to my TV" then a Pi makes a lot of sense. If you want to have a resilient case, be portable, have a small screen attached, etc, then maybe a phone makes more sense.

Re:Arduino Uno

[girlintraining]

Solid, lots of add-on modules, vibrant hacker community. And it has its own programmable processor so if your application permits you don't even have to have it attached to your PC to collect and process data.

Limited memory, slow I/O, slow processor, can emulate a USB device but can't function at anything resembling modern USB speed... This guy doesn't want another bag on the side, he wants something that gives him a spread of I/O pins and sampling options. And Arduino ain't that -- and he's right, there's nothing on the market that will give him a programmable DAC/ADC paired with a USB controller that can operate at the speeds of the current USB standard (v3).

It's not hard for an electronics engineer to slap some glue logic and a few chips on a homebrew board and do it, but for a hobbyist who just wants to play? Forget it.

Re:Arduino Uno

[chrylis]

Of course nothing's going to operate at USB v3 Super-Speed. You'd have to be running custom FPGA hardware to get anywhere close. On the other hand, the IOIO seems to be about as close to what the submitter wants as is practical with cheap hardware.

Re: Pearls before swine?

[Anonymous Coward]

If you can't figure out that the asker has already figured that out that they're not the Pi's target market, and isn't questioning the Pi's utility for its target market, you're not insightful.

You're a fanboy. Go play with your Pi.

Re:Arduino Uno

[50000BTU_barbecue]

What would a hobbyist that can't handle a few logic chips do with a super fast DAC/ADC? No offense, but this sounds more like a gee-whizz hardware equivalent of a warez dood. You want a DAC ADC combo? It's called a 5$ audio card. If you need multi GHz sampling you can't even begin to do that properly with only hobbyist-level knowledge and equipment. Unless you are into building sub-samplers. But that's a very esoteric niche that long ago broke the multi-100 GHz barrier, so it's inaccessible even for well-to-do hobbyists. Again, what for?

I have a 14GHz sub-sampling scope from the 1960s, it's fun to keep working as a hobby and it is part of my lab, but people who actually need such measurements need traceability which I can't provide anyways.

You are better off just settling down and buying a USB oscilloscope.

Ask better questions, get better answers

[inglorion_on_the_net]

Why Buy a Raspberry Pi When I Have a Perfectly Good Cellphone?

Because you can install your own operating system on your Raspberry Pi, but not on your cellphone?

Because you want to support the Raspberry Pi foundation?

There are many possible answers.

It seems to me that even the most outdated cellphone has far superior features (screen, touch screen, Wifi, 3g/4g camera(s), battery etc) in a much better form factor.

If the combination of those is what you're looking for, then maybe you want a cellphone. Why are you comparing a cellphone against a Raspberry Pi?

The only thing that is missing are the digital/analog in/out pins. So why not flip it around and make a USB or bluetooth peripheral board with just the pins? I've been looking for this and can't find any, but does anyone know of any in the corners of the internet? I don't care what phone platform.

What are you going to do with it? How are you planning to do it? You don't care what phone platform? Don't you at least want one that you can run your own code on? Preferably with enough privileges that you can actually drive your shiny peripheral?

Here's the thing: Tell us what you're trying to do, and maybe we can help you, possibly by giving some recommendations for hardware to work with.

As it stands, your question is more flamebait than helpful. You're stating that you think even outdated cellphones are superior to a devices that some of us really like, without stating what purpose you think cellphones are superior for. That gives us little opportunity to be helpful, and plenty of opportunity to feel slighted.

Re:Arduino Uno

[harrkev]

First, a disclaimer. I am not an Arduino expert. I have one and have played around, but am not a pro. Please forgive me if I make a mistake...

The big thing is that Arduino does NOT have Ethernet. Yes, you can add it on. I just built a small project for an internet-controlled power outlet. Raspberry Pi + an SD card (around $40 total) is significantly cheaper than an Arduino plus an Ethernet shield (around $60). Plus, the Pi can be programmed in your choice of languages (Python, Perl, TCL, C++, etc.) while the Arduino . Also, a web server on Pi is just an "apt-get" away. Don't get me wrong. The Arduino has its place too. Lots of IO. analog input, PWM output, etc. But the Pi and Arduino are different beasts with different (but somewhat overlapping) targets.

Now, the concept of using a phone as a general-purpose controller is interesting, if you can overcome the IO problem. If you can find something and cobble it together go for it. However, finding a steady supply of phones would be problematic. I could order a dozen Raspberries or Arduino boards in a moment. Using an old cell phone would require hitting garage sales or thrift stores looking for old phones that actually run something you can use (such an Android). I don't think that you can program older "feature phones." You probably need something with full-blown iOS or Android, and I doubt that an older iOS device is cheaper than a Pi. That leaves Android. If you only need one or two for a particular project, you might be able to swing it. Otherwise, you can't beat a couple of mouse clicks to get a proper development platform delivered to your door for under $50.

Re:People often fail to understand why the Arduino

[Joce640k]

People often fail to understand why the Arduino is so fucking popular. It is NOT because it has the most powerful processor. It is NOT because it has the most pins. It is NOT because it is the easiest to develop for. It is NOT because it is the most standardized.

This.

Just yesterday I had an 'argument' with a guy over how Arduino is dead because such-and-such a chip is way more powerful than AVR (AVR=the chips in Arduinos), how it has hundreds of MegaHertz and Megabytes and all that stuff.

I simply don't care! I don't need a board that has 512Mb of RAM and runs Linux just to light up a few LEDs (even with a motion sensor!). I need something that works well enough, can drive a LED directly from an I/O pin (5V outputs, tada!) and has a huge online community with thousands of web pages/blogs/forums to browse, plus source code to download.

PS: Can you build your own dime-sized clone of that fancy ARM board for $1.50? I can do it with Arduino... (ATtiny85)