How/what exactly does the 74ls00 do in 5200 protos?

[82atari5200]

I know it's used for chip select, but can someone explain it a little more detailed than that? Like can I program 2 2764 eproms for a 16k cart and just swap them out for mask roms? I see they are also used in xe games so how does that work with a 27c512? And why does the 32k eprom carts that were sold here use a 74ls04? What's the difference?

[mightywiz]

it's a logic gate.....specifically a NAND gate.

2 input's with an inverted output.

 

using Boolean algebra:

NAND GATE

 

 

A B C

0 0 1

0 1 1

1 0 1

1 1 0

 

a and b are inputs, c is the out come.

 

in digital circuit you have different type of logic gates

AND

NAND

OR

NOR

 

and others just google Boolean algebra and it will give a better description.

Edited May 5, 2014 by mightywiz