USB permissions for educational robots

Alan Jhonn Aguiar Schwyn alanjas at
Mon Jan 2 21:55:33 EST 2012

In a few of months, all our High Schools (of Uruguay) will receive and robotic kit (Lego).
At "Universidad de la RepĂșblica", "Facultad de IngenierĂ­a" we are workingwith it and the XO...

In other parallel road, we are working on a 2.0 version of the Butia Robot

That uses USB4all IO board  which resulted from a thesis given at ourUniversity (also will have arduino compatibility)

USB4all is based on 18f4550 pic.The vendor is Microchip, SYSFS{idVendor}=="04d8"And have: productID=0x000b //bootloader          productID=0x000c //pic18f4550 generic comunication

The actual Sugar image, only have permissions for LEGO WeDo.
If you see in: /etc/udev/rules.d you find the correspondient: "30-olpc-wedo.rules".
The file add this rule:
SYSFS{idVendor}=="0694", SYSFS{idProduct}=="0003", GROUP="dialout", MODE="0660"
This means: 0694 is LEGO                   0003 the model: WeDo
To the NXT we need add: {idProduct}=="0002"
But, for each model add a new line.. not is a good form..
Exist another way, a generic rule:
BUS=="usb", SYSFS{idVendor}=="0694", GROUP="lego", MODE="0660" 
That says: if is USB and fabricated by 0694 (LEGO) lets 0660 (4: read+ 2: write)
If add this permissions to "lego" group, we need create it..
But, we don't make it, an use an existing group like "root"? Or another... Suggestions?
We can make a generic group "robot" that have permissions for: lego wedo, lego nxt, butia, etc...
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