I have moved over from analogue electronics to digital electronics, Is there a trick to remmembering the 6 basic gates and there logic How are these linked to binary
The output of the other three gates (NAND, NOR, XNOR) are just the opposite of their respective matches.
The binary nature of these parts is due to the fact that they can only be in one of two states: HIGH or LOW. There is no inbetween. Because only two states exist, the system is binary.
I have moved over from analogue electronics to digital electronics, Is there a trick to remmembering the 6 basic gates and there logic How are these linked to binary
0 and 1 can be confusing since in positive logic, 1 = high & 0 = low but in negativelogic, 0 = high & 1 = low.
So it is less confusing to use "active high" and "active low".
eg. when a NAND gate is used as an AND gate it has active high inputs and an active low output. Or if it is used as an OR gate, it has active low inputs and an active high output.
That's interesting Ron, but I would have thought that the output of a true 3 input XOR would be 1 when only one of the inputs = 1, but the truth table in the paper also has the output = 1 when A, B & C are all equal to 1.
In relay logic there is a "one only chain" which is active (ie. there is a connection through it) when one and only one of a group of relays is operated, ie. a true XOR.
That's interesting Ron, but I would have thought that the output of a true 3 input XOR would be 1 when only one of the inputs = 1, but the truth table in the paper also has the output = 1 when A, B & C are all equal to 1.
In relay logic there is a "one only chain" which is active (ie. there is a connection through it) when one and only one of a group of relays is operated, ie. a true XOR.
I didn't look far enough down the truth table! I was thinking the same as you. Since the 3 input XOR is defined as {A XOR B XOR C}, it makes logical sense, but not common sense.
Wouldn't the output of a true 3 input XOR gate only go high when all inputs are exclusive, ie all different. That would be a 1, a 0 and a something else input.
Wouldn't the output of a true 3 input XOR gate only go high when all inputs are exclusive, ie all different. That would be a 1, a 0 and a something else input.
Interesting point, but of course it doesn't work in the binary number system.
I was thinking that exclusive OR is the 'opposite' of inclusive OR. Inclusive OR is where the output is true if one or more inputs is true. Exclusive OR would then be true if one and only one input is true (one input is true, to the exclusion of all others).