Microcontroller Articles

Page 5 of 33

AD7-0 pins in 8085 Microprocessor

Ankith Reddy
Ankith Reddy
Updated on 27-Jun-2020 961 Views

The Intel 8085 is an 8-bit microprocessor produced by Intel and introduced in 1976. It is a software-binary compatible with the more-famous Intel 8080 with only two minor instructions added to support its added interrupt and serial input/output features. When the 8085desires to receive 8-bit information, it receives it on these eight pins AD7, AD6, …, AD0. These eight pins are collectively called AD7-0. They are called basically “Address Data”. When the 8085 desires to send out 8-bit information, it sends it out on these same pins. these pins are bi-directional pins.The same lines are used for both receiving information and ...

Read More

2's complement notation

Ankith Reddy
Ankith Reddy
Updated on 27-Jun-2020 5K+ Views

This is one of the methods of representing signed integers in the computer. In this method, the most significant digit (MSD) takes on extra meaning.If the MSD is a 0, we can evaluate the number just as we would any normal unsigned integer.If the MSD is a 1, this indicates that the number is negative.The other bits indicate the magnitude (absolute value) of the number.If the number is negative, the other bits signify the 2'scomplement of the magnitude of the number.Thus a positive number has the same representation in SM, 1's complement, and 2's complement notations. Only negative numbers are represented ...

Read More

Representation of fractions

Chandu yadav
Chandu yadav
Updated on 27-Jun-2020 2K+ Views

To represent fractions may be necessary quite often inside the computer. For example, it may be needed to represent inside a computer a value like +0.610 or -0.610. To represent signed fractions, it is necessary to assume the binary point just after the MSB in the bit sequence. Such numbers where the binary point is assumed to be at a fixed position in the bit sequence are called fixed-point numbers.Unsigned fractions will have the assumed binary point at the extreme left. SM, 1's complement, and 2's complement fractions will have this imaginary binary point just to the right of the ...

Read More

2's complement fractions

George John
George John
Updated on 27-Jun-2020 6K+ Views

As an example, the value of 1 001, if the interpretation is that it is a 2's complement fraction will be as follows -It is 1.001 assuming the binary point after the MS bit. As the MS bit is 1, it is a negative number. Then the remaining bits do not specify the magnitude directly. The 2's complement of 1 001 is 0110+ 1 = 0 111. This is a positive fraction with the value 1 × 2−1 +1 × 2−2 +1 × 2−3 = 0.5 + 0.25 + 0.125 = 0.875 decimal. Thus, -0.875 is the value of 1001.If ...

Read More

Signed floating point numbers

Arjun Thakur
Arjun Thakur
Updated on 27-Jun-2020 2K+ Views

Were present real numbers in our daily life is not convenient for representing very small numbers, like +0.00000012347650. This same number can be more conveniently represented in scientific notation as +1.23476× 10−07. But this actually stands for +0.000000123476. So there is an error of 0.00000000000005, which forms a very small percentage error.Floating-point representation is similar in concept to scientific notation. Logically, a floating-point number consists of:A signed (meaning positive or negative) digit string of a given length in a given base(or radix).This digit string is referred to as the significand, mantissa, or coefficient.A signed integer exponent which modifies the magnitude of ...

Read More

Unsigned binary integers

Ankith Reddy
Ankith Reddy
Updated on 27-Jun-2020 5K+ Views

Unsigned binary integers are numbers without any ‘+’or ‘-’ sign. Here all bits representing the number will represent the magnitude part of the number only. No bits will remain reserved for sign bit representation. An unsigned binary integer is a fixed-point system with no fractional digits.Some real life Examples are −Number of tables in a class, The number of a member of a family.Obviously, they are unsigned integers like 10 and 5. These numbers have to be represented in a computer using only binary notation or using bits.Numbers are represented in a computer using a fixed size, like 4, 8, ...

Read More

Sign Magnitude notation

George John
George John
Updated on 27-Jun-2020 12K+ Views

The sign-magnitude binary format is the simplest conceptual format. In this method of representing signed numbers, the most significant digit (MSD) takes on extra meaning.If the MSD is a 0, we can evaluate the number just as we would any normal unsigned integer. And also we shall treat the number as a positive one.If the MSD is a 1, this indicates that the number is negative.The other bits indicate the magnitude (absolute value) of the number. Some of the signed decimal numbers and their equivalent in SM notation follows assuming a word size of 4 bits.Signed decimalsign-magnitude     +6   0110    ...

Read More

1's complement notation

Arjun Thakur
Arjun Thakur
Updated on 27-Jun-2020 6K+ Views

This is one of the methods of representing signed integers in the computer. In this method, the most significant digit (MSD) takes on extra meaning.If the MSD is a 0, we can evaluate the number just as we would interpret any normal unsigned integer.If the MSD is a 1, this indicates that the number is negative.The other bits indicate the magnitude (absolute value) of the number.If the number is negative, then the other bits signify the 1's complement of the magnitude of the number.Some signed decimal numbers and their equivalent in 1's complement notations are shown below, assuming a word ...

Read More

Interfacing 8279 Keyboard with 8085 Microprocessor

Chandu yadav
Chandu yadav
Updated on 27-Jun-2020 3K+ Views

Here we will see how 8279 Chip can be used to interface a matrix keyboard with 8085 microprocessors. This chip can be used either keyboard/display interfacing mode or as a strobed input port. But generally, it is used as keyboard interfacing.The keyboard interfacing schemes can also be divided into two modes. These modes are Decoded mode of operationEncoded mode of operationDecoded Mode of OperationIn this mode, the matrix keyboard can have only four rows. These four rows can be selected by using SL3-0 select lines. There are eight columns. These can be selected using RL7-0 these eight column lines. So there are ...

Read More

Interfacing 8279 Display with 8085 Microprocessor

George John
George John
Updated on 27-Jun-2020 4K+ Views

The Intel 8279 is used for keyboard interfacing but it can also be used for multiplexed 7-segment LED display interfacing. To display a character into 7-segment display we have to store 7-segment code in a display RAM location. The display RAM of this chip can store 16 bytes of data.Write to Display RAMTo write to the display RAM one special command is needed to be applied on the 8279 control port. The following pattern is showing the RAM command that is written to the control port of 8279.100AiAAAAThe first three bits are 100. It indicates ‘ Write to Display RAM’command. ...

Read More
Showing 41–50 of 321 articles
« Prev 1 3 4 5 6 7 33 Next »
Advertisements