Microcontroller
“Microcontroller used to execute a single task.”
The word Microcontroller is composed of two terms micro and controller. ‘Micro’ means very small in size. The word ‘controller’ means a device which controls the operations of all the devices. So we can say that microcontroller has the ability to control any device and also small in size. Microcontroller consists of various components. Microcontroller has built-in RAM, ROM, serial input output ports, peripheral devices, timer, counters, clock circuit etc. Microcontroller generally consists of all these devices. RAM is the random access memory. ROM is the read only memory, timer, counters etc. Microcontroller generally consists of all these devices. We can say that microcontroller is nothing but it’s an on-chip computer. All the devices of computer are embedded on a single chip that will be called a microcontroller.
8051 Microcontroller Features:
Microcontroller consists of 8 bits bus. It can write, read, and process up to 8-bits data so it is called 8 bits microcontroller. 8051 consists of 16 bit address bus. It having 64Kb of RAM and ROM. On chip RAM having 128 of data memory. On chip ROM consisting of 4kb of memory which is used for program memory. On chip ROM stores a program memory whereas on chip RAM stores data memory. It has four 8 bit for 8 bit bi-direction input/output ports. 8051s having UART (Universal a synchronous receiver transmitter). It’s a serial port. 8051 microcontroller consisting of two 16 bits timers and two levels interrupt priority.
8051 Microcontroller Uses:
Microcontroller has the ability to control all the functions. Microcontroller is used in any application so they will access the dedicated devices which are controlling all the functions. Microcontroller can be used as the engine controllers in the automobiles. They are also used in the washing machines, VCD players, and microwave ovens for controlling the temperature. Microcontroller is also used in cameras to exposure and focus. So in all the applications where controlling is required microcontrollers can be used. By the use of CMOS technology the size of these microcontrollers is very small.
8051 Pin Diagram
Pin Number | Function | Description |
P3.0 – 10 | Rx | Serial input |
P3.1 – 11 | Tx | Serial output |
P3.2 – 12 | INT0 | External Interrupt 0 |
P3.3 – 13 | INT1 | External Interrupt 1 |
P3.4 – 14 | T0 | Timer 0 |
P3.5 – 15 | T1 | Timer 1 |
P3.6 – 16 | WR | External memory write |
P3.7 – 17 | RD | External memory read |
8051 Microcontroller Pinout Explanation:
In microcontroller there are 4 ports. P0, P1, P2 and P3. We called it as bank. In port P1 pins from 0 to 8 does not perform any function. It is internally pulled up bi directional port. It is just input/output port. It can act only input port as well as output port. Pin num 9 is reset pin which is used to reset the microcontroller initial value. Pin 10 to 17 is known as port 3. The purpose of these ports is interrupt, timer input and serious communication signals. P3.0 act as receive data. P3.1 act as transmit data. P3.2 and P3.3 is interrupt signals. P3.4 and P3.5 is timer input T0 and T1. P3.6 and P3.7 act as control signals where p3.6 is write signal and P3.7 is read signals. Pins 10 to 17 act as interrupt, timer input, control signals, serious communication signals. Pin 18 and 19 external crystal which represent as system clock. Pin 20 is GND means ground. Pin 21 to 28 is port 2. These pin serve as input and output port as well as high order address bus. Pin 29 represent PSEN (Program store enable). It is use in to read a signal from external program memory. Pin 30 is ALE (address latch enable pin). That is used for the separation of external address from data. Pin 31 is EA (external access). It is use to enable or disable the external memory interface. Now pin 32 to 39 is port 0. This port used as input output, lower order data and address signals are multiplexed. Pin 40 Vcc is used to provide power supply to this circuit.
Getting Started With 8051 Microcontroller With Proteus Simulation
With the help of this microcontroller we are going to construct a circuit in proteus. But first we have to select the components from proteus libraries.
- 7 segment display
- Traffic light
- Microcontroller 8051
7 Segment display:
7 segment displays is the most common device for displaying digitals and Alphabet. The binary information can be displayed in the form of decimal using his seven segment display. Seven segment displays are made up of either LED’s or LCD (liquid crystal display). These LED or LCD are used to display the required numerical or alphabet. Single seven segments or number of segment arranged in an order meet our requirements. It consists of 10 pins. 8 are LED pin. 2 pins in the middle are common pins and these are internally shorted. The common pin is cathode and other is anode. From the top view 8 segments can be seems. Here the 7 LED’s called segments and are labeled a through g where h is representing the dot point for displaying. Thus each seven segment display will have seven pins used for displaying the digits (0 to 9).
8051 Microcontroller
Microcontroller used to execute a single task. Microcontroller consists of various components. Microcontroller has built-in RAM, ROM, serial input output ports, peripheral devices, timer, counters, clock circuit etc. Microcontroller generally consists of all these devices. RAM is the random access memory. ROM is the read only memory, timer, counters etc. Microcontroller generally consists of all these devices. We can say that microcontroller is nothing but it’s an on-chip computer. All the devices of computer are embedded on a single chip that will be called a microcontroller.
Microcontroller consists of 8 bits bus. It can write, read, and process up to 8-bits data so it is called 8 bits microcontroller. 8051 consists of 16 bit address bus. It is having 64Kb of RAM and ROM. On chip RAM having 128 of data memory. On chip ROM consisting of 4kb of memory which is used for program memory. On chip ROM stores a program memory whereas on chip RAM stores data memory.
Traffic light:
Traffic lights are used for sequence controller. They help reduce the number of accidents on the road. They play an important role when it comes to safety in our everyday lives. They are placed on roads at intersections and crossings. The different colors of light tell drvier what to do.
Red LED
Means you need to make a complete stop before crosswalk or before intersections to allow other road users who will use the intersection or crosswalks.
Yellow LED
Yellow also means stop. In the event that you are not able to stop safety, proceed with caution. In situations when you are in the middle of the intersextion when the light switches to yellow, you are still allowed to proceed, but do will extreme caution.
Green LED
Green like go but only when the intersection is clear. You must yield to pedestrains, who are crossing, ever if the light is already green.
So, that was all for today. I hope you have enjoyed today’s topic. Will meet you guys in the next tiem wit another intereting topic. Take care and have fun.