AVcc is, unfortunately, exactly what it says: the Vcc power supply pin. So, nope. Can't shut it off without shutting off the whole telos board. You will need to use one of the other digital I/O pins.
Your problem is that a motor draws more current than can be supplied by a regular output pin. If you just want to run your DC motor in one direction you can use a "common-emitter" transistor driver to boost the current. E.g. look for it here: http://www.williamson-labs.com/480_xtor.htm mshrehm...@gmail.com has also given you another option, using a "Hobby Servo" motor, which contains a driver of it's own and is operated using variable width pulses from a digital I/O pin. Along with the ease of hardware interface you also get speed and direction control, but you have somewhat more complicated software in making the right pulses. Here's some more info: http://www.horrorseek.com/home/halloween/wolfstone/Motors/svoint_RCServos.html http://www.junun.org/MarkIII/Manual/kevin/servohack.html Where the second site actually sells some of the motors. Usually hobby servos are used for setting rudders and flaps and such where you want to go to a specific angle, but they can be modified for continuous rotation (I think there are some that are continuous, but it's been a while since I looked). I have posted code for ATMEGA timers and hobby servo control here: http://www.etantdonnes.com/Motes/AVR128timers.zip I don't know how easy it would be to port the timer code to MSP chips. Also, should you actually need speed control, I've hacked the servo back into the hacked servos by adding an encoder: http://www.etantdonnes.com/ROBOCAR/encoder/ MS Imene Boudellioua wrote: > Hi, > > Is there a ways to set the AVcc pin in Telosb (Pin 1 in the 10-[in > expansion connector U2) to low, or clear it? I want to be able to turn > it on and off to control a DC motor. I need this for my project to > control a small DC motor. I tried connecting the DC motor to pin 9 (Gnd) > and any pin set to 1 but it was not working for some reason. However, > when I connect it to Gnd and AVcc, it works perfectly. Is there a way > to turn the AVcc pin manually in tinyos? if not, what will be the > solution to my problem? > > Thank you in advance. > > Amy > > > ------------------------------------------------------------------------ > > _______________________________________________ > Tinyos-help mailing list > Tinyos-help@millennium.berkeley.edu > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help _______________________________________________ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
