some first impressions
wmb at laptop.org
Sat Aug 11 04:28:38 EDT 2007
Hal Murray wrote:
>> - some parallel port (or similar) should be made available, for
>> children to play with in physics. I remember playing with a PC
>> parallel port with some simple software to turn leds on and off. When
>> you are a kid, being able to send commands to projects you create is
>> great (think about modern legos, but using simpler stuff like leds,
>> motors, etc) : it translate the "virtual part" ie the software you
>> create on the computer to the "real world" where you make leds blinks
>> in sequence, or a motor move.
> There are USB connectors.
> USB to printer port adapters are also available. I've never played with one.
> Prices are under $40.
> There are also things like this with 24 GPIO lines.
> US distributor: http://www.orteches.com/ $75
> There is also the microphone input and audio output for A/D and D/A. I think
> the XO hardware supports a DC coupled mode.
> We should work on a collection of hacks to demonstrate how they work and a
> list of which ones are known to work.
OLCP just had a summer intern, Arjun Sarwal, who developed some low-cost
gadgets to plug into the mic port - temperature sensor, intrusion
detector, etc. He plans to document them and set up a framework for
documenting other similar hacks.
We also talked about an OLPC digital gadget prototyping dongle with a
USB-equipped microcontroller like those available from, for example,
Atmel. Those chips cost a dollar or two and Arjun can get all the other
parts really inexpensively in India where he lives.
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