In this project we will interface a relay with pic microcontroller pic16f877a. Write a program to blink the led 1 if sw5 is on and blink the led2 if sw6 is on. Different dc motors need different voltages and operating high voltage motor from a low voltage controller is not a feasible option. For interfacing relays, a npn transistor is generally preferred. The embedded ethernet solutions are offered with 10 baset and 100 baset phys.
Perhaps one of the most entertaining things to do with an embedded microcontroller is to get it to actually move something. Interfacing circuits with microcontrollers, in this article i have discussed various elements and circuits interfacing with microcontrollers. Embedded design by interactive simulation 1st edition this edition is a comprehensive guide to interfacing microcontrollers based on the io devices of the pic 16f877 chip, including keypads, displays, analogue, timers and a full range of serial peripherals. Relay is a mechanical device to control high voltage, high current appliances on or off from lower voltage levels. Microcontroller components, a typical microcontroller application, motorola 68hc12 microcontroller, 68hc12 programming model, 68hc12 data types, auto prepost decrementincrement, indexed addressing, 68hc12 move instructions, hc12 logic instructions, multiply and accumulate. Manufacturer of the pic microcontroller range and mplab ide. If you want to use more relays, using transistors will be difficult.
In this project we will interface a relay with pic microcontroller pic16f877a and control a 220v ac lamp using the relay. This application note provides an example schematic and software for using the ds5 realtime clock rtc with a pic microcontroller. In the multiprocessor system, processors can send interrupts to each other as communication between them, for example for the. A relays is an electrical switch that opens and closes under control of another electrical circuit. Here i used diode d11n4148ws, resistor r1 1k, transistor t1 bc547, 12 v power supply and 6v relay. Ted salazar, applications engineering manager sep 29, 2003 abstract. Additionally, each device has a unique, factorypreprogrammed mac address and. To facilitate multiple features with simple circuits, microcontroller is interfaced with devices such as adc, keypad, lcd. Microcontroller boardscontrol the relay operations by using pic16f18f slicker board.
If possible, the relay should be powered by a separate power supply to enable a connection of relays requiring a different voltage like for example a 12v relay which is. From mechanical to solid state relays, there are various type of relays are. Interfacing a relay with pic microcontroller mikroc. The maximum current that a pic microcontroller can source or sink is 25ma while a relay needs about 50 100ma current. External hardware devices are sending interrupts to microcontroller in order to receive the treatment. Using the microchip pic18 family as a reference, it explains the architecture of the computer and the pic18 microcontroller, discusses how to program in both assembly and in clanguage, and then provides a solid discussion of interfacing, complete with. Wireless radio frequency rf communication between two microcontroller step by step.
Relay module interfacing with pic16f877a microcontroller. Automatic street light control using 8051 micro controller,keil ide and proteus simulation duration. A pic microcontroller is a single integrated circuit small enough to fit in the palm of a hand. This lab session will look at how you can interface a dc motor to a pic microcontroller. Interfacing dc motor with pic microcontroller using l293d. For detailed working of relay please visit this page. Interfacing dc motor with pic microcontroller mikroc. Peripheral interface controller pic is new to elec. A relay can be used to switch high power devices from a. Dc motors need much more current than a microcontroller can provide, so it needs separate drivers.
This will establish a serial connection between both. Relay provides isolation between two voltage levels and it is generally use to control ac appliances. Then i iniatized uart in pic send and received data to pc through hyperterminal its working properly. Gsm interfacing with pic microcontroller pic16f877a make. Interfacing relay with pic microcontroller youtube. So we connect output from our microcontroller pin to the base of transistor. Relay interfacing with pic16f877a friendly free download as pdf file. The connection diagram for interfacing gsm module with pic microcontroller is shown below. It is therefore connected to ouput pins of the microcontroller and used to turn onoff highpower devices such as motors, transformers, heaters, bulbs, antenna systems etc. Interfacing converter to the picmicro microcontroller. I am interested in simple controlling via lan such as switching led onoff. As you can see an npn transistor bc547 is being used to control the relay. Programming with pic microcontroller research design lab.
Peripherals interfacing to the microcontroller 8051 in. From mechanical to solid state relays, there are various type of relays are available in. How to turn on and turn off relay with pic microcontroller by using digital output ports of pic16f877a microcontroller. Internally relay consist of a coil of wire wrapped soft iron core.
The input is taken from the microcontroller pins and the output corresponding to each input is given to the 5 relays on the output. In order to control devices, it is necessary to interface or connect them to the pic microcontroller. It should not be directly connected to a pic microcontroller. See the block diagram of driver circuit which i used in my project. Pdf design and implementation of electronic control trainer with. I am beginner in the microcontroller world, i started to work with pic mcus and writing simple programs in assembly. The image below show the schematic symbol for a npn transistor. How to interface relay with pic16f877a pic development board. Microcontroller may stop working by the negative voltages produced in the relay due to its back emf. Now lets take a look on rf transmitter and receiver respectively.
A very small current flowing from base to emitter causes a large current to flow from collector to emitter. Microcontroller interfacing techniques document revision. A 32bit arm7 microcontroller is used in interfacing and software examples. So by using relay switch we easily turn on or off any high voltage device by microcontroller. See the block diagram below to how we turn on or off a 230 volt ac bulb by micro controller. It is activated by energizing a coil wounded on a soft iron core. Part 1 introduces the pic 16f877 architecture, software, and simulation system. Interfacing relay with pic microcontroller mikroc electrosome. A relay is a switch which is used to switch high voltage or current using low power circuits. Interfacing a relay to a pic microcontroller if possible, the relay should be powered by a separate power supply to enable a connection of relays requiring a different voltage like for example a 12v relay which is different form the 5v supplied to the microcontroller.
We can drive two dc motors with one l293d, in this example we are using only the first pair of drivers to drive one dc motor. I am doing a project in which i will be interfacing a gsm modem with pic microcontroller16f877 when i connect the gsm modem with pc i can able to send and read the messages in the sim using at commands in hyperterminal. Embedded design by interactive simulation discusses microcontroller design and applications. Microcontroller basics pdf slides 46p this book covers the following topics. Relay module interfacing with pic16f877a microcontroller ac load. Ive got pic16f877a on my development board and microchip ethernet interface enc28j60. Relay interfacing with pic16f877a friendly pic microcontroller. Ds5, spi, pic, real time clock, rtc, spi interface, pic microcontroller application note 2361 interfacing an spiinterface rtc with a pic microcontroller aug 25, 2003 abstract. To control our high voltage device like home appliance by pic microcontroller, we have to have clear idea on interfacing relay with pic microcontroller.
Following things should be taken into account while designing the. These are monolithic ic s consists of high voltage high current darlington transistor arrays. Led blinking using pic controller 16f877a with mplab. As it can be seen from the above circuit diagram, a uln2003 is connected between the microcontroller and relays in order to drive multiple relays. Limit the current in input led of optocoupler to 10ma by the resistance and output of it is an npn transistor, connect it as you require.
Interfacing is one of the important concepts in microcontroller 8051 because the microcontroller is a cpu that can perform some operation on a data and gives the output. Pdf this paper describes the implementation of a pic microcontroller in a. The transistor is driven into saturation turned on when a logic 1 is written on the port pin thus turning on the relay. Before interfacing, every one should know about the relay driver which is used to interface the relay to microcontroller. You need a max232 in between so that it can scale down the voltage values to a range of 05v because microcontrollers cant handle more than that.
Relay isolates low power circuits from high power circuits. A relay is an electromagnetic switch which is used to switch high voltagecurrent using low power circuits. Relay module interfacing with pic16f877a microcontroller, in this pic microcontroller tutorial you will learn how to interface relay module with any pic microcontroller or any microcontroller. How to interface rs232 with a microcontroller quora. Martin bates has drawn upon 20 years of experience of teaching microprocessor systems to produce a book containing an excellent balance of theory and practice with numerous working examples throughout. Interfacing pic microcontrollers, 2nd edition is a great introductory text for those starting out in this field and as a source reference for more experienced engineers. In this tutorial, we will learn about the interfacing of the relay relay connection with microcontroller and learn how to control a device using the relay. To interface relay with microcontroller we need a driver circuit to drive the power to relay. Interfacing relay with pic microcontroller using uln2003. Interfacing of relay with microcontroller aticleworld. Rf modules are popularly used in remote control system.
The picmicro mcu offers many options for smart solutions. Optocoupler interface with pic microcontroller its very easy, connect any port pin you desire to pin number 1 of 817c through a resistor, and pin number 2 to ground. Interfacing the max1169 adc to a pic microcontroller. As the pic microcontroller operates at 5v a potential divider formed from resistors must be used to reduce the pic microcontroller output signal to 1. You can connect seven relays using uln2003 and eight relays using uln2803. Interfacing is a technique that has been developed and being used to solve many composite problems in circuit designing with appropriate features, reliability, availability, cost, power consumption, size, weight, and so on. However to perform the operation we need an input device to enter the data and in turn output device displays the results of the operation. Relay interfacing with pic microcontroller pic16f877a. These ad converter modules are primarily successive approximation register sar type and range in functionality from 8 to 12bit with channel size ranges of 4 to 16. Three very popular devices used to make things move include dc motors, rc servos, and stepper motors. Vdd and vss of the pic microcontroller is not shown in the circuit diagram. Pic microcontrollers can be used as the brain to control a large variety of products. These circuits are useful for those who want to work on embedded system projects, but thy dont have a knowledge of electronics and embedded electronics. You cannot directly interface an rs232 cable with a microcontroller.
As we did previously in bluetooth interfacing with pic microcontroller tutorial. Relay interfacing with microcontroller 8051 microcontroller. Sign up to get notified when this product is back in stock. The rf modules wireless module such as rf transmitter and rf receiver are interfaced to the microcontroller with the help of decoder and encoder ics. Microcontroller interfacing circuits pdf 44p download book. We have simply interfaced the tx and rx pins of the gsm module with the rx and tx pins of the pic mcu pic16f877a respectively. So, can use those two components together for some simple. This section will help to enable those with limited electronics experience to successfully complete these interfacing tasks. Electromechanical relays interfacing circuits with. Learn how control high power devices from a microcontroller using a relay in mikroc. The micro can send to itself an interrupt as a result of executing the code to report the failure in the process.
Interfacing relay with pic microcontroller using transistor. Applications of interfacing devices with microcontroller. Relay interfacing with pic microcontroller pic16f877a circuit digest. This book provides a comprehensive look into the architecture, programming, and interfacing of the microcontroller.
233 523 1429 228 1145 425 240 1105 898 555 899 1454 484 709 16 310 109 1056 873 705 408 1180 882 518 768 109 1204 565 1115 1389 366 193 970 737 1075 601 1279 305 106 887 752 127 744 1123 1455 143 1286 671 1366 1481