can you help me to design 1 bit BCD adder using 7483
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BCD binary numbers represent Decimal digits 0 to 9. A 4-bit BCD code is used torepresent the ten numbers 0 to 9. Since the 4-bit Code allows 16 possibilities, therefore thefirst 10 4-bit combinations are considered to be valid BCD combinations. The latter sixcombinations are invalid and do not occur.BCD Code has applications in Decimal Number display Systems such as Counters andDigital Clocks. BCD Numbers can be added together using BCD Addition. BCD Addition issimilar to normal Binary Addition except for the case when sum of two BCD digits exceeds 9 ora Carry is generated. When the Sum of two BCD numbers exceeds 9 or a Carry is generateda 6 is added to convert the invalid number into a valid number. The carry generated by addinga 6 to the invalid BDC digit is passed on to the next BCD digit.Addition of two BCD digits requires two 4-bit Parallel Adder Circuits. One 4-bit ParallelAdder adds the two BCD digits. A BCD Adder uses a circuit which checks the result at theoutput of the first adder circuit to determine if the result has exceeded 9 or a Carry has beengenerated. If the circuit determines any of the two error conditions the circuit adds a 6 to theoriginal result using the second Adder circuit. The output of the second Adder gives the correctBCD output. If the circuit finds the result of the first Adder circuit to be a valid BCD number(between 0 and 9 and no Carry has been generated), the circuit adds a zero to the valid BCDresult using the second Adder. The output of the second Adder gives the same result. Figurr
THEORY:
Circuit that takes the logical decision and the process are called logic gates. Each gate has one or more input and only one output.
OR, AND and NOT are basic gates. NAND, NOR and X-OR are known as universal gates. Basic gates form these gates.
AND GATE:
The AND gate performs a logical multiplication commonly known as AND function. The output is high when both the inputs are high. The output is low level when any one of the inputs is low.
OR GATE:
The OR gate performs a logical addition commonly known as OR function. The output is high when any one of the inputs is high. The output is low level when both the inputs are low.
NOT GATE:
The NOT gate is called an inverter. The output is high when the input is low. The output is low when the input is high.
NAND GATE:
The NAND gate is a contraction of AND-NOT. The output is high when both inputs are low and any one of the input is low .The output is low level when both inputs are high.
NOR GATE:
The NOR gate is a contraction of OR-NOT. The output is high when both inputs are low. The output is low when one or both inputs are high.
X-OR GATE:
The output is high when any one of the inputs is high. The output is low when both the inputs are low and both the inputs are high.
PROCEDURE:
(i) Connections are given as per circuit diagram.
(ii) Logical inputs are given as per circuit diagram.
Observe the output and verify the truth table