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Showing content with the highest reputation on 11/13/2010 in all areas

1. ## Powering LEDs With MSP430 Output

Just another source: http://www.physics.unlv.edu/~bill/PHYS483/transbas.pdf
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2. ## Powering LEDs With MSP430 Output

A picture is worth a thousand words... maybe.
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3. ## Powering LEDs With MSP430 Output

Yes, if you look at the doc cde quoted before. Your LED would go in between R1 and Q1. Except in this case, 12V supply would be 5V and 5V would be ~3V at the MSP430 pin. Turn the pin High to turn the LED on, and Low to turn it off.
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4. ## Powering LEDs With MSP430 Output

The transistor does not act like a switch (as I thought at first as well), but more of a "valve". It will only allow roughly the same voltage to pass from collector to emitter as is applied to the base, but it will allow much higher current (which is the limitation of the MSP430 we are overcoming here). In the diagram I posted, bringing the MSP430's output pin high (~3v) will allow about 3v to pass for the LED circuit. You'll need to calculate the resistor value to restrict the current within the limits of the LED (average is about 20 milliamps) and for the brightness you desire. The
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5. ## Powering LEDs With MSP430 Output

No, not with a diode. The TI wiki has a nice page on driving an led from a msp430 with a transistor http://processors.wiki.ti.com/index.php ... _Drive_LED Its the basic NPN transistor usage. Output of the msp430 gpio tied to the Base pin of the transistor, with the Emitter pin tied to ground, and the Collector pin connected to the negative side of the led. For multiple leds, you can tie them in series, which means you need a higher voltage (3 blue leds at 3.6 typical voltage would require 10.8 volts atleast, with 12v being the standard voltage) and one resistor, or you can tie the
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7. ## Repurposing a Nokia adapter cable - Request for info

Find the Vendor ID, and Product ID of the usb device, and you'll find the driver in no time. Its a bit tricky to find in windows, but http://www.tomshardware.com/forum/12863 ... oduct-list has some info. And for what its worth, most knockoff nokia cables have actual chips in them, not just chips-on-blobs like you do. Seems like an original cable.
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8. ## Repurposing a Nokia adapter cable - Request for info

i brought 4 this year from, one ca-42 from dealextreme at \$4.44 (shipping incl), this is the one i used for the spectrum analyzer. http://www.dealextreme.com/details.dx/sku.446 another two ca-42 from two different ebay sellers (\$2.00, each, shipping incl), one more dku-5 from ebay, i was trying to find those older types that has 4/5 wires (Vcc incl.) but to my disappointment, all are the same inside, 3 wires having the same pcb. if u get them, i can provide a short write-up / diagrams to show the best way to hack and use it. w/o any modification u can immediately use it (free from
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9. ## You can Thank users now!

Hi All, 43oh has a new feature, where you can "Thank" users if their posts have been helpful to you. You will see a tiny "Thumbs Up" sign on the top right of every post, except yours..as you can't thank yourself :mrgreen: . This also adds two fields to your profile. Hope you guys like it and make use of it.. Thank away!
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