What:
A Digital Circuits designed to add (Computer) Bit together. They’re designed in such a way so they can be strung together to add a full binary (32bit/64bit) numbers.
FA Truth Table:
A (Input 1) | B (Input 2) | Cin (Carry In) | Sum (S) | Carry Out (Cout) |
---|---|---|---|---|
0 | 0 | 0 | 0 | 0 |
0 | 1 | 0 | 1 | 0 |
1 | 0 | 0 | 1 | 0 |
1 | 1 | 0 | 0 | 1 |
0 | 0 | 1 | 1 | 0 |
0 | 1 | 1 | 0 | 1 |
1 | 0 | 1 | 0 | 1 |
1 | 1 | 1 | 1 | 1 |
Data Overflow:
If the last full adder has a carry-out of 1, many ALU’s will simply set a flag in a registry saying something has gone wrong. Otherwise, it may just continue on as normal, causing the error to propagate onwards.