Demonstration of a N x N multiplier with 4-bit numbers.

This is a part of a project to construct a 4 BIT CPU from scratch. I will be starting with a simple NOR gate and building it up to a working model with ALU registers, RAM and ROM. I will be designing an op code and assembler to go with it. Progress and detail can be found on my blog here

This file cotains 4 bit versions of basic logic gates.

studying purpose

4 Bit Comparator circuit

A - A3 A2 A1 A0 B - B3 B2 B1 B0

A = B when, A3=B3,A2=B2,A1=B1,A0=B0.

A>B when, A3>B3 OR A3=B3 AND A2>B2 OR A3=B3 A2=B2 AND A1>B1 OR A3=B3 A2=B2 A1=B1 AND A0>B0.

A<B when, A3<B3 OR A3=B3 AND A2<B2 OR A3=B3 A2=B2 AND A1<B1 OR A3=B3 A2=B2 A1=B1 AND A0<B0.

This is My 4 Bit computer with 6 instructions just like the SAP Computer. :)

Instructions:

00 NOP

1x LDA

2x ADD

3x SUB

ee OUT

ff END

Warning:

This computer cannot calculate more than 2 numbers

This Example Program shows 5+7 and 4-5.

To Program, Set the Reset Bit to 1 and Program the ROM.

To Run the Program, Set the Reset Bit to 0.

The Numbers in the output are in Two's Complement so if the number is more than 7

than the number will be negative because 7 is the biggest number in 4 bits.

My first project on this site!

this 4 bit adder is fully decimal, that means the number you input is decimal and the answer will also be in decimal.

The circuit consists of a decimal-to-binary converter, an 4 bit adder and a binary-to-decimal converter.

The circuit is made without sub-circuits.

To use the adder, click any number you want on the left and right side of the plus. The answer will appear on the right side, in decimal and binary.

KPGW

The 4-bit adder which can do math on 4-bit integers and display on 2 7-segment LEDs.

This project is owned by Lu Xuan Minh - student of HCMUT.

Everyone can fork my project for the purpose of studying and researching.

Thank you for your viewing!

Lu Xuan Minh

Email: **[email protected]**