From: Alan Womack <arwomack01@wo...> - 2002-11-28 18:49:00
>> Your description leads me to suspect that you havent got power and ground
>> the chip. Those connections are not shown in typical schematics, only the
>> signal lines. There should be connections to two ther chip pins, one
>> and one ground. Havent got a chip manual handy, so I cant tell you which
>> pins, but often opposite corners.
I thought that perhaps this might be the case and went ahead and connected pin =
8 to power and pin 4 to ground. I just measured the voltage across them to be =
I also suspect there should be a ground line back from the computer? Otherwise =
how does pin 7's circuit get closed?
Am I incorrect in my understanding this circuit should go HIGH when a light is =
strong on the photo cell and be LOW all other times? It appears I am always =
What could be next to check on?
Thanks for the help, this will be a fun little toy when it functions.