NNNOOOOOO 0 Report post Posted May 17, 2011 The reset pin seems to be always held high, even though I GROUND it. STORY: Yesterday, I went to Radio Shack to buy a push-to-make switch and a bridge rectifier. I decided not to get the rectifier for a certain reason. Well, Radio Shack didn't have any plain old switches for less than 50 cents. They had lighted ones. I bought one with a thought in my head. It had four pins: 2 pins for the actual switch, 2 for the LED. My thought was to set it up so that when the switch (SPST) was in the "off" position, the LED was always on, but in the "on" position, the LED flashed. I knew this could be achieved with a 555 timer. I used a simulator to plan how the circuit would be built. I then build the circuit. Guess what? The circuit requires the "reset" pin to go low. That doesn't happen. How do I make the "reset" pin work? Share this post Link to post Share on other sites
rvalkass 5 Report post Posted May 17, 2011 The reset (pin 4) is normally connected to the input power supply by a 10k resistor, and then connected to ground when you want to activate the "reset" part of a bistable circuit (between pin 3 and ground). Make sure you've connected every other pin of the 555 timer correctly, and that there are no shorts. If that doesn't help, post your circuit diagram and we'll take a look. Share this post Link to post Share on other sites
NNNOOOOOO 0 Report post Posted May 17, 2011 Didn't work. What I first tried and should've worked: WHY WON'T IT WORK?!!? Share this post Link to post Share on other sites
rvalkass 5 Report post Posted May 17, 2011 Pin 4 (reset) is connected incorrectly. Take a look at this page for how to connect it correctly: http://forums.xisto.com/no_longer_exists/ Share this post Link to post Share on other sites
NNNOOOOOO 0 Report post Posted May 17, 2011 This's what I need it to do: http://www.4shared.com/video/6G0za9yh/yenka_2011-05-17_17-21-44-648.html Remember: The LED AND switch is the same unit in real life. Share this post Link to post Share on other sites
NNNOOOOOO 0 Report post Posted May 29, 2011 I figured it out, the timer is bad. Used a new timer and it works. BTW, if anyone knows about the sensor kit from RS, does the LED display run on logic or analogue? Share this post Link to post Share on other sites