# Which is unused combination in excess 3 code?

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## Which is unused combination in excess 3 code?

Why are 1010, 1011, 1100, 1101, 1110 and 1111 unused codes in Excess-3 code? – Quora. Firstly, the numbers listed in the question are unused codes in BCD. Unused codes in XS-3 are 1101, 1110, 1111, 0000, 0001, 0010. These codes are unused because XS-3 is based on BCD.

## How many don’t cares conditions are there for BCD to excess 3 code converter?

The ‘don’t care conditions’ is expressed by the variable ‘X’. To find the Excess-3 code of the given Excess-3 code, first, we will make the group of 4 bits from right to left. Then, we will add 0011 in each group of 4 bits in order to get the excess-3 code.

## What must be done to change the circuit to an excess-3 to BCD code converter?

What must be done to change the circuit to an excess-3-to-BCD-code converter? Feed BCD-code to the 4-bit adder as the first operand. Feed constant 3 as the second operand. The output is the corresponding excess-3 code.

## What are the applications of excess-3 code?

The primary advantage of excess-3 coding over non-biased coding is that a decimal number can be nines’ complemented (for subtraction) as easily as a binary number can be ones’ complemented: just by inverting all bits.

## What is the key feature of excess-3 code?

The key feature of the Excess-3 code is . that it is self complementing. In other words, the l’s complement of an Excess- 3 number is the Excess- 3 code for the 9’s complement of the corresponding decimal number. For example, the Excess- 3 code for decimal 6 is 1001.

## Why do we convert BCD to excess-3 code?

It is particularly significant for arithmetic operations as it overcomes shortcoming encountered while using 8421 BCD code to add two decimal digits whose sum exceeds 9. Excess-3 arithmetic uses different algorithm than normal non-biased BCD or binary positional number system.

## What is excess 3 code example?

For example: If we perform 1’s complement of the excess-3 code 1000(decimal 5), complement value will be 0111, which is the excess-3 code of 9’s complement of 5, i.e., 4(0111)….The Excess-3 code for the decimal number is as follows:

Decimal Digit BCD Code Excess-3 Code
3 0011 0110
4 0100 0111
5 0101 1000
6 0110 1001

## How do you write an Excess-3 code?

We can easily get an excess-3 code of a decimal number by simply adding 3 to each decimal digit. And then we write the 4-bit binary number for each digit of the decimal number….The Excess-3 code for the decimal number is as follows:

Decimal Digit BCD Code Excess-3 Code
2 0010 0101
3 0011 0110
4 0100 0111
5 0101 1000

## What is the difference between BCD and Excess-3 code?

BCD stands for Binary Coded Decimal. The table describes, input variables of BCD input are designated as A,B,C,D and variables of Excess-3 code are designated as W,X,Y and Z. Excess-3 code output is obtained by addition of 0011 to the BCD data input.

## How to convert BCD code to Excess-3 code?

The BCD (binary coded decimal) code is basically 8421 code and the conversion of 4-bit input BCD code ( A B C D) into the excess-3 code output ( W X Y Z) as shown in truth table 1. Table 1: BCD to Excess-3 Code Converter. From this truth table, the K-maps are drawing shown in Figure 1, to obtain a minimized expression for each output.

## How to design a BCD to excess-3 circuit?

In this topic, you study how to design BCD to Excess-3 Code Converter Circuit and draw the logic diagram. The BCD (binary coded decimal) code is basically 8421 code and the conversion of 4-bit input BCD code ( A B C D) into the excess-3 code output ( W X Y Z) as shown in truth table 1.

## How are decimal numbers expressed in BCD code?

8421 Code or BCD Code The decimal numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 can be expressed in Binary numbers as shown in the following table. All these binary numbers again expressed in the last column by expanding into 4 bits.

## Are there any other codes besides BCD code?

These may be considered as binary codes. Other than the 8421 code or BCD code, 2421 code, 5211 code, reflective code, sequential code, non-weighted code, excee-3 code and Grey code are some of the codes which were popularized.