What is a BCD code, what is a BCD code What is a BCD code used for?

BCD code is also called 8421 code is to decimal number in the form of 8421 into binary, we all know that the decimal system is 0 9 ten numbers composition, with ten numbers each number has its own 8421 code:

For example, 321 is 8421 yards.

The BCD code isDecimal number of binary yardsor two solsticeDecimal**。This coding technique is most commonly used in the design of accounting systems, which often require accurate calculations on long strings of numbers. Compared with the general floating-point notation, the use of BCD code can not only save the accuracy of the value, but also eliminate the need for the computer to do floating-point operations.

time spent on chain annihilation. In addition, BCD codes are commonly used for other calculations that require high accuracy.

BCD code encodingThe most commonly used BCD code is to use the binary code of ten values from 0 to 9 to represent the beam punch. This encoding method is called 8421 code. In addition, different coding methods have been developed to meet different needs.

These codes can be roughly divided into two kinds of right codes and no right codes: the right to BCD code, the scum guess such as the right to BCD code, such as: the remaining 3 code, Gray code.

BCD code, refers to:A "four-digit binary**" that represents a one-digit decimal number.

The point is: the four-digit two-in envy beam system**! These four-digit binaries come in a variety of combinations.

Therefore, there are many kinds of BCD codes.

The list of judgments sent out of the bureau to dig and let some of them are as follows:

BCD code travel god, group fight refers to: represents a decimal number"Four-digit binary**".

These four-digit binaries come in a variety of combinations. Collapse of the mill.

Therefore, there are many kinds of BCD codes.

Some are listed below

The BCD code is also called 8421 code, which is the decimal system.

The number is in the form of 8421 into binary, as we all know, the decimal system is composed of 0 9 ten numbers, each of these ten numbers has its own 8421 code: 0 0000 1 0001 2 0010 3 0011 4 0100 5 0101 6 0110 7 0111 8 1000 9 1001

For example: 321 8421 code is 3 2 1 0011 0010 0001 Reason: 0011=8x0+4x0+1x2+1x1=3 0010=8x0+4x0+2x1+1x0=2

0001=8x0+4x0+2x0+1x1=1

Specifically: BCD code is a four-digit binary code, that is, the decimal number is converted into binary, but it is a little different from the ordinary conversion, each decimal number 0-9 corresponds to a four-digit binary code, the correspondence is as follows: decimal 0 corresponds to binary 0000; Decimal 1 corresponds to binary 0001 ...

9 1001 The next 10 has two of the above codes to represent 10 is 00010000, that is, the BCD code is to meet 1001 to produce carry, unlike ordinary binary code, to 1111 to produce a carry 10000

The BCD code is a manual fabrication.

It is a variety of combinations of four-digit binary systems that represent one-digit decimal numbers.

BCD code refers to a decimal number"FourBinary**”。

These four megabytes of bright binary come in a variety of combinations.

Therefore, there are many disadvantages of BCD code. Rent guess whoa.

Some are listed below

The BCD code uses a 4-digit binary number to represent a 1-digit decimal number, and in the data format of Step 7, the BCD code only takes a positive number. The length of the int data is 16 bits with the BCD code, but there are positive and negative points.

BCD code: A form of binary numeric encoding.

BCD code refers to the "four-digit binary**" representing the decimal number.

BCD code, which comes in many forms.

Among them, only the 8421bcd code is suitable for calculation.

If it's not 8421bcd code, don't discuss the calculation of the swift opening. Mu Bu years

Use a 4-digit binary number to represent the 10 digits 0 9 in a 1-digit decimal number, referred to as BCD code, that is, BCD**. binary-coded

Decimal, abbreviated as BCD, is called BCD code or binary decimal **, also known as binary code decimal number. It is a form of binary numeric encoding, with binary encoded decimal**.

Non-BCD code, that is, in addition to the Bi Liang Hall BCD code, hand-hidden such as hexadecimal code key.

The operation rules of the BCD code: The BCD code is a decimal number, and when the combinator adds and subtracts the data, it is processed according to the binary operation rules. In this way, when the BCD code is passed to the combinator for computation, the result needs to be corrected.

The rule of correction is: when the sum of two BCD codes is added, if the sum is equal to or less than 1001 (i.e. the decimal number 9), no correction is required; If the sum is between 1010 and 1111, it needs to be corrected by adding 6; If the base produces a carry when adding, it also needs to be corrected by adding 6.

The reason for this is that the machine adds according to binary, so when the 4-digit binary numbers are added, it is calculated according to the principle of "every sixteen into one", and Liang Na is essentially the addition of 2 decimal numbers, which should be added according to the principle of "every ten into one", 16 and 10 are 6 apart, so when and more than 9 or there are carry places, 6 must be added for correction.

There are many types of BCD codes. Rent reserve

Some BCD codes, which belong to "non-authoritative codes", have no arithmetic function at all.

If it's an 8421bcd code, you can add and subtract it like a normal binary number.

It is relatively simple to do arithmetic operations manually, and when you need to "every ten", you just need to pay attention to it.

If you use a computer to add and subtract, it will be more troublesome.

Because, the computer can only do binary, so the result it calculates must be the binary imitation jujube trillion system.

Then, after the fact, a "decimal adjustment" must be made to get the result of the BCD code.

A circuit for "decimal adjustment" is as follows: