Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: jhonilson on March 03, 2008, 08:05:42 PM
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Hi, I want to make a lamp similar to some webcam, is to say, i want to ignite some led with the usb port, but i think that it will need some resistors. I think that if i connect a resistor (330 ohm for example) with a led (ultra brilliant) perhaps the usb port died because is too corrent for it.
Anybody can help me about that?? I visited usb.org but in the datasheet not speak about the current only voltages.
Thanks
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usb ports handle 500ma. do you want the led to turn on always or be program activated?
heres a site to help you calculate the resistor needed http://led.linear1.org/1led.wiz
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Thank you so much for you answer. 500 mA is fine for me. The leds use 25 to 30 mA aproximately. Yes i would want to control when turn on the leds. i am thinking to make a software with visual basic, but may be any software.
Gracias
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with USB you'll need a translator. too complicated for me to help you with.
but there is this http://www.codeproject.com/KB/cs/csppleds.aspx
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with USB you'll need a translator. too complicated for me to help you with.
but there is this http://www.codeproject.com/KB/cs/csppleds.aspx
get a USB to serial converter
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Thank Ed1380 i saw the same webpage yesterday and other nice website but i not found many details about how controlling the usb port really.
Airman00 i think that the port converter i will help too much because i will need to control the usb port anyway i think and that is the real problem.
Thank you so much
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you could try this and modify the code to do a constant on or off to power the leds intead of the pwm for the servo's
http://www.societyofrobots.com/member_tutorials/node/25