I picked up a Model B from Amazon earlier this month, here in the US. I have been really impressed with it, even though I paid ~$48. Very impressive device in such a little package. I used mine to make a WiFi garage door opener with node.js backend and iOS app to open our garage doors from our phone. So many more projects in mind.
Really cool. Could you point me towards any resources for learning the electronics side of this? I've had my pi for awhile and want to get into the hardware aspect of it more, but have zero experience.
I don't know too much about hardware, enough to solve simple issues like this. The relay simply closes the circuit as if I pressed the wall switch. The Pi has header pins with power, ground, and programmable pins. Check out the WiringPi page though. https://projects.drogon.net/raspberry-pi/wiringpi/
That's an awesome project! I got mine in January, cost around the same. It's currently running as a portable git/file server but I've been looking for a more hands-on project for it. I'm not really in need of a garage door system, but your post was quite cool to read. :)
So, only one vendor, and they state back orders not accepted, and they state they have 0 in stock.
Which means it's not really on sale for $25 in the US.
I could make the same claim myself, that I am selling them for $25, don't have any in stock, and don't accept backorders. They wouldn't make it really for sale unless I am actually accepting $25 and shipping out boards. It might be convenient though if I give people a link to where I am selling other items, that's a lot of free incoming traffic without having to pay Google for AdSense clicks.
This is just cheap dishonest advertising for the company. A lot of people visiting the link will buy something else. Someone there has figured out a good way to make money is send out press releases to the tech press about their desirable but unavailable non-sale item, and hope for a bite. They got a bite - Cyrus Farivar at ArsTechnica fell for it. Sure, they had 50 in stock that were sold instantly. 50 that this company no doubt bought for more than $25 each and either sold as a loss leader, or simply charged more for shipping than they paid.
It has been amazing watching what people have done with the Model B. I'm actually considering picking one up just to play around with web development and all these mysterious languages I hadn't heard of before reading Hacker News, ie the *.js languages, and a personal trial of Django vs Rails.
Your current computer almost certainly will run a Linux virtual machine with more than enough performance to try out Django, Rails, Node and more, for free. It'll also be much closer to the kind of environment you would likely deploy on (64 bit x86 vs 32 bit ARM).
That's not to say you shouldn't get a Raspberry Pi, quite the opposite - just don't let the lack of one stop you from doing what you want, today!
Micro instances have savage CPU throttling with a little bit of leeway. What this translates into is you'll compile something biggish (eg node.js), things will seem fine for a few minutes, then the machine appears to freeze. *
If you want to keep a machine around that you know doesn't do much, it's the cheapest option on AWS. But it's no fun if you're doing unplanned, interactive work. Even for the first use case, you want to fire up a bigger instance to do things like package installation, then restart as a micro once its configured.
(* I experienced this a year ago. Others report similar things.)
If you don't want to run full up Linux you can do this with the ST Micro STM4F32, its Cortex-M4 chip with ethernet capability. At about the same price (in small quantities) you can use the Atmel SAM9 series, just chip, memory, ethernet MAC, and USB is about $25 in parts (single unit quantity) so if you made a bunch your cost would be closer to $15 but if you sell them you need to make some sort of profit to cover the cost of building them.
Close though, and I suspect we'll see SOC's that target this market soon enough. One workaround is a development environment that lets you compile a Linux application into something that can run on the hardware (just the kernel you need, and nothing extra :-) The uC Linux work is interesting in this regard.
Removing the ethernet port is one of the things they did to get the cost down to 25 dollars. The gfx/video you get for free with the CPU, so I dont think you're right.
The ethernet was expensive because it consisted of two components, an ethernet chip and a usb hub. A cool side effect of the hub not being in the A is that you can use it as a USB slave too. This is very handy if you want to use the Pi to make a pheripheral device.
I wonder if just providing a wireless chip would be cheaper than just providing ethernet?
There must be some cost saving in just removing the video connectors from the board, though I'm not sure if it's any cheaper to get an ARM CPU without an inbuilt GPU.
I think the difference is that you perhaps pay 2cts for a video connector which is directly connected to an output your cpu has and a few euro for a networking chip that requires high quality crystals etc.
Model A is very restrictive than the B, if you are even slightly serious to do sth of little weight with it. I wonder if A can withstand always-on torrent and/or a connected hard disk which is constantly filled by CrashPlan or Time Machine. One USB port is another big restriction. Kills my idea of making it work with two hard disk(without using a hub).
PS. It hurts to think that I am not buying it(B) because it costs ~$60 here(IN) and the original price being $35. Maybe I would have bought it if it was released for $60 and available here for the same cost. Played with it at a friend's place though.
The model B achieves the 2 usbs and an ethernet port by having a builtin hub this means your 2 hdd's compete both with eachother and with the network for bandwidth so your no hub constraint doesnt make sense.
The problem is that it's manufactured and sold by a UK non-profit, so you're importing it to India. You may be able to get it cheaper by buying it from someone outside of the country and shipping it to India. I'm not sure if importing for private vs. commercial use matters or not in India.
I do something similar. You will need a powered USB hub to attach the external HDD (built-in USB can't supply the full 500 mW that a USB port is supposed to supply). Checkout out Plugable's videos on youtube.
I have a Model B with a connected HDD that's been on 24x7 for a few months now. No problems so far. I don't expect a big difference between the Model A and B wrt stability.
Shameless plus as I just wrote a post about my project this weekend. http://itsbrent.net/2013/03/hacking-my-garage-with-a-raspber...