The 8085 is an 8-bit general purpose microprocessor that can address 64K Byte of memory. It has 40 pins and uses +5V for power. It can run at a maximum frequency of 3 MHz. The pins on the chip can be grouped into 6 groups: Address Bus. Data Bus. Control and Status Signals. Power supply …
What are instruction sets? The 8086 microprocessor supports 8 types of instructions − Data Transfer Instructions Arithmetic Instructions Bit Manipulation Instructions String Instructions Program Execution Transfer Instructions (Branch & Loop Instructions) Processor Control Instructions Iteration Control Instructions Interrupt Instructions Let us now discuss these instruction sets in detail. Data Transfer Instructions These are the instructions …
What are instruction sets in microprocessor 8086? Read More »
In certain situations when creating a program by the user we often find some sort of disturbances suddenly where the program stops abruptly. it might be due to some technical problems by hardware or software etc. This interrupt indicates immediate attention which alerts the microprocessor and instructs as to how to handle the interrupt. So, …
What is 8086 Interrupts and various types of Interrupts? Read More »
What are addressing modes of 8086? It is a type of mode where the source operand is specified in various forms in an instruction.There are 8 different addressing modes in 8086 programming − Immediate addressing mode The addressing mode in which the data operand value is a part of the instruction itself is known as …
As the name itself indicates that Multiprocessor means multiple set of processors. It is a multiple set of processor that helps in executing the instructions simultaneously. There are three basic multiprocessor configurations. Coprocessor configuration Closely coupled configuration Loosely coupled configuration Coprocessor Configuration A Coprocessor is a specially designed circuit which is placed on microprocessor chip …
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8087 Architecture is divided into two groups, i.e., Control Unit (CU) and Numeric Extension Unit (NEU). The control unit maintains the communication between the processor and the memory such as receiving and decoding instructions, reads and writes memory operands, maintains parallel queue, etc. All the coprocessor instructions are considered as ESC instructions, i.e., they start …
Architecture/Functional block diagram of 8087 Numeric Data Processor Read More »
8087 numeric data processor is also popularly called as Math co-processor, Numeric processor extension and Floating point unit due to its faster calculations. To make easier and faster calculations this math coprocessor was first designed by Intel and was paired up with 8086/8088. As these instructions are identified by the 8086/8088 processor, it is then …
Interface acts as a communication between user and a computer. It is an integrated circuit which helps in performing basic functions of the CPU. Interfacing is classified into two types, memory interfacing and I/O interfacing. Memory Interfacing If any instruction is executed then we require microprocessor to access the memory in order to read the …
8279 Programmable Keyboard acts as an input device contains maximum of 64 keys. With the help of keyboard the user can perform various types of tasks. Certain specific key-codes are used where text is entered as an input with the keyboard. The main function is to act as an interface with the CPU with the …
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It is a specially designed type of programmable keyboard/display controller launched by Intel which helps in interfacing the keyboard with the CPU. It identifies any type of key that has been pressed with the help of scanning. It then sends the response of the pressed key to the CPU and vice-a-versa.
8257 DMA stands for 4-channel Direct Memory Access. It is specially designed by Intel for data transfer at the highest speed. Its initial function is to generate a peripheral request which allows the device to transfer the data directly to/from memory without any interference of the CPU. With the use of a DMA controller, the …
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The following table highlights the differences between a microprocessor and a microcontroller − Microcontroller Microprocessor Microcontrollers are used to execute a single task within an application. Microprocessors are used for big applications. Its designing and hardware cost is low. Its designing and hardware cost is high. Easy to replace. Not so easy to replace. It …
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A microcontroller is a smaller computer inserted on a single integrated circuit, less sophisticated which consists of the processor, the memory(RAM,ROM,EPROM), peripherals (timers, counters), programmable input or output etc. It is specially designed to perform certain operations and can be used in embedded systems like vehicles, printers, automobiles, refrigerators receiving remote signals, etc. Difference between …
8051 microcontroller is a type of microcontroller designed by Intel in 1981. This microcontroller architecture is based on the Harvard architecture and was developed basically for the use in embedded systems technology. Basically this microcontroller was revised one and the updated one came into existence with CMOS technology. It is an 8-bit microcontroller. It is …
What is the functional block diagram and pin description of microcontroller 8051? Read More »
The 8255A is generally seen as 8-bit bidirectional data buffer, which is specially designed to transfer the data with the execution of input output instructions requested by the CPU. It has the ability to use with almost any microprocessor. It consists of three 8-bit bidirectional I/O ports (24I/O lines) which can be configured with their …
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Let us first take a look at the pin diagram of Intel 8255A − Now let us discuss the functional description of the pins in 8255A. Data Bus Buffer It is a tri-state 8-bit bidirectional data buffer, which helps in interfacing the microprocessor to the system data bus. Data is transmitted or received by the …
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The programmable Interval Timer are specially designed by Intel called as 8253 and 8254 constructed for microprocessors to perform timing and counting functions by using three 16-bit registers. Each counter has 2 input pins, i.e. Clock & Gate, and 1 pin is for “OUT” output. To perform a counter, a 16-bit count is loaded in …
8253/54 consists of 6 different modes which perform specific operations. In this chapter, we will discuss these operational modes. Mode 0 ─ Interrupt on Terminal Count It helps in generating an interrupt to the microprocessor after a specific interval. Initially the output becomes low after the mode is set. The output becomes LOW when the …
To perform input/output operation Microcontrollers 8051 possess 4 I/O ports each consisting of 8-bit, which can be configured as input or output. Hence, out of 40 pins only 32 input/output pins are allowed for the microcontrollers that are connected with the peripheral devices. As microprocessor does not have inbuilt input/output operation, it can be rectified …
How interrupts occur in microcontrollers? Interrupts are the sudden obstruction that halts the main program for some time, this in turn passes the control to the external sources in order to execute their task. After completing the task it again returns the control to the suspended main program where it had get halt. 8051 consists …
MICROCONTROLLERS 8051 INTERRUPTS – MICROPROCESSOR Read More »