Calculator using Logic Gates

4 bit Calculator using Logic Gates

1-reminder

2-addition/subtraction

3-multiplication

Reminder

Extendable Reminder using :

1-3 subtractors(3 adder and xor )

2-piority encoder and mux -> for choosing the right value

3-nor -> for division of zero error

idea (A%B)

we subtract the A three times and get the value before become negative

Addition / Subtraction

Extendable Adder / Subtractor using :

1-adder

2-4 muxs -> to choose the complement value or the real value

3-2 And / 2 OR -> for zero error

4-5 Xor / 1 OR -> to complement the numbers => (two inputs - one output)

idea (+-A +- +-B)

-if the input sign negative we convert it to it's 2nd complement .

the second input sign xor with the operator(+ or -) give the real sign if it.

-we add them using adder.

-if there's a carry out from adder mean that the output negative and it's need to convert it to it's 2nd complement state.

-if not means that's positive output and it's correct.

Multiplication

Extendable Multiplication using :

1-3 xor -> 1 for sign and rest for A1, A2

2-6 And -> to get carries

idea (+-A * +-B)

-the first output is A0B0

-the second output is A0B1 + B0A1 and carry(C) out

-the third output is A1B1 + C and carry(C) out

-the fourth output is C

Collection

we use:

1-4 mux -> for o1,o2,o3,sign 

2-and -> for o4 =>  as it out from multiplication only

3-OR/And for flags and show sign

4-7-segment IC converter

Teammates

I work on this project with Ali Farid, Mahmoud Farid and Omar Said