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yea , sorry for the sloppy code writing and thx Dave Was actually in a hurry to see what u have to say about the ISIS simulation and how to manipulate the relay better (not sure I am activating it at all at this point). Posting a pic to catch your attention large here
Ah, I may have found your problem. Look closely at your relay. The driver IC (U2) is connected to the COMMON input to the relay. How is the relay actuated?
Perhaps if you connected the driver IC to the COIL(-) in the relay, and connected the other side of the coil to VCC, your relay would actuate?
Also, note that the ANODE side of your DIODE is connected to the COIL(-) side of the relay, and the CATHODE side of your DIODE is connected to the COIL(+) side of the relay. This DIODE is referred to as a SNUBBER DIODE, which means that it will "snub" (or remove) the large stored charge in the coil when it is released. Sometimes, this is referred to as "back EMF", and can be hazardous to your circuitry. A very good idea to have this DIODE in place.
Now, when you actuate the relay, not much will happen, because you have nothing connected to the COMMON pole, nor do you have anything connected to the NORMALLY-OPEN pole... so connect a voltage source to the COMMON pole, and connect your latch release to the NORMALLY-OPEN pole. Make sure to connect the other side of your latch to the common for your voltage source, whatever that might be.
Now when you activate your output from your micro controller, the driver should actuate the relay, and your door latch should move...
One final note: The relay may not be necessary, if the latch current is not too high. What I mean is that U2 may be able to drive your latch by itself... Double check the requirements for your latch, and see how much current it takes to work...
Hope this helps,
[ Edited Thu Jun 04 2009, 02:26PM ] -Dave "Basic research is what I am doing when I don't know what I am doing"
Correction... http://www.8051projects.net/lcd-interfacing/lcd-4-bit-programming.php That gave me headaches... Mismatched coding between the 4-bit and 8-bit sections.
The #1 reason why I have my own blog is because I can be very sarcastic at times... I just don't want to cause problems. Hopefully my MCU projects will get me offline and back in to reality.
Ajay, I write my posts, offline, with Windows Live Writer. The problem over here is, http postings fail due to a TinyProxy Cache error from my ISP. I've written huge http posts and lost it all after clicking the submit button.
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and thx Dave
or tomorrow 
