First, let me go on the record as saying I'm a huge Raspberry Pi fan. If you haven't heard already, a Raspberry Pi is a small but complete $35 computer (or $25 without Ethernet). It's a complete 700 MHz ARM CPU with a GPU and 256MB of RAM. It has two USB ports, Ethernet, Audio as well as video out over RCA (Composite) or HDMI at 1080p. It uses an SD Card for its hard drive and takes 5V at >700mA of power over a mini USB. You can order one from Farnell online and there is a waiting period.
All that said, I wanted to talk about some misconceptions one might have about these amazing little devices.
The Raspberry PI is a tiny little joy. The boys are having great fun with it and frankly I'm happy that it's hard. I don't want them using an Xbox or some "easy" technology. They are using espeak from the command line to get the computer to talk to them and are learning how to read. As they get older I hope we'll start trying out some of the hundreds of other uses for these tiny devices.
We spent all day today building a LEGO case then found a clever design online as well. The little Pi community is having such fun and I think it's because of the device's constraints. It's small, it's cheap, but it's got such potential. If you are aware of it's limitations and are armed with a little patience, you'll have a blast introducing your kids to the Raspberry PI.
Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. I am a failed stand-up comic, a cornrower, and a book author.
Generally speaking the model B raspberry PI was designed only for <100mA USB devices! That is because the PI's PSU was chosen with a power budget of 700mA in mind of which 200mA were assigned to the two USB ports, so the raspberry PI's (poly)fuses were designed only for <100mA devices, and typical 140mA polyfuses will have as much as 0.6 volt across them when drawing currents near the 100mA limit. As a consequence the USB ports are only directly suitable for "single current unit" USB devices which according to USB specifications are designed to work with just 4.4 Volt. Not only do non single current unit devices draw more current, (causing greater Voltage drops, and greater stress on the fuses) they also might require 4.75 Volt to work. Therefore any non single current unit devices will only work when powered from a powered hub.
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Disclaimer: The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.