Help with IC logic gate chips

[bacteria]

Bought a couple of logic gate IC chips, one is the 74HC08 chip

I actually want to use an AND and also an XOR chip to decide which of two connections to connect a circuit to (the Intellivision matrix).

On the AND I know the logic is "If A1 AND B1 are on, then Y1 is on, otherwise off".

Here is a datasheet, there are one or two others around: http://www.datasheetcatalog.com/datashe ... HC08.shtml

For testing purposes, as I expect the circuit to be "on" or "off", I wanted to connect an LED into the output (added a 75ohm resistor to protect the LED) so when I press two buttons the LED illuminates.

Connected 5v to the VCC line and ground to the grounding pin. Couldn't work out how to connect button contacts to the circuit so the LED comes on when both buttons are pressed. If I can do this, I can remove the LED and replace with what I need.

Help?

[MrPopo]

Wouldn't you just connect a voltage source to one pin of each of the buttons, the other pin to each of A1 and B1 and then see if you get voltage out of Y1? Or am I missing something in your description of what you're trying to do? If both switches are on you should get ~Vcc out because of how the transistors that make up the logic gates work.

[zxqdms]

I think you would use a pull-down resistor. Connect a resistor from ground to the input, then connect one button contact to the input, and the other to Vcc. When the button is open, the input is grounded through the resistor. When the button is closed, the input is connected to Vcc, and a voltage drop occurs across the resistor.

[bacteria]

Thanks so very much, got my AND logic gate working now!

I'm going to upload a video on this in due course as part of my online guides, to hopefully help others, when i've got it all working.