KwickClips Computer Systems · 43 sec · free
How many bits does a full adder take in?
Short answer. 3: A, B and carry in.
What joins the two carries?
An OR gate.
Full adder
| Half adder 1: A and B |
| Half adder 2: sum and Cin |
| OR gate joins both carries |
Remember
| Full adder takes 3 bits |
| 2 half adders + 1 OR gate |
A half adder cannot take a carry in. What can? A full adder. Half adder one adds A and B. Half adder two adds that sum and the carry in. An OR gate joins the carries. Two points. Three bits in. Two half adders and an OR.
This clip is from the full lesson: Adders and Combinational Circuits: Half Adder and Full Adder — 8 minutes, with the tables, the quick answers and the whole lesson in text.
Useful for: ISC Class 11 Computer Science (868), ISC Class 12 Computer Science (868), ISC Class 12 Computer Science (868), Programming All levels C
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