INTRODUCTION TO INTELLECT SPEED BREAKER USING CAN PROTOCOL
This project deals with limiting the speed of the vehicle by employing technology of embedded systems using “Peripheral Interface Controller (PIC 16F877A)”, when the vehicle enters the speed limiting zone. The parameter to be controlled in this project is speed.
PIC has the advantage of enhanced FLASH memory with the modified Harvard architecture and having simple 35 instructions. A Controller Area Network (CAN) protocol is ideally suited to automobiles. Performance of CAN and its upgrade ability leads to effective system design. This protocol is immune to Electromagnetic interference (EMI) effect and rugged surfaces, so the transferred data is sent to destination without any error.
Hence by implementing RFID based speed breaker using CAN protocol, vehicle speed slow down automatically in the speed limiting zone and regains its speed when it leaves from the speed limiting zone. Thus the concept of automated speed breaker is achieved.
1.1 BLOCK DIAGRAM
PIC 16F877APIC 16F877A
(CAN ENGINE) (CAN ENGINE)
MCP2551 CAN PROTOCOLMCP2551
1.2 CIRCUIT DIAGRAM
Unlike microprocessor, microcontroller are generally optimize for specific applications. The first 8-bit microcontroller, the Intel 8048 was introduced in 1976. It was designed to control the specific tasks.
2.2 DIFFRENCE BETWEEN MICROPROCESSOR AND MICROCONTROLLER
| | | |MICROPROCESSER |MICROCONTROLLER | |Microprocessor contain ALU, general purpose register, stack |Microcontroller contains circuitry of microprocessor and in | |pointer program counter, clock timing circuit and interrupt |addition it has built-in ROM, RAM, I/O device, timer, counters. | |It has many instruction sets. |Instruction set is reduced. | | | | |It has 1 or 2 bit handling instruction. |It has many bit handling instruction. | |More access time |Less access time | |Requires more hardware. |Requires less hardware. | |More flexible in design point of view. |Less flexible in design point of view. |
2.3 PIC MICROCONTROLLRE
The Microcontroller has many reasons to be used than the microprocessor. Other than the normal microcontroller PIC Family supports more features, so PIC 16F877A has been chosen as the main controller. The main features and peripherals are discussed blow.
2.3.1 CORE FEATURES
• High RISC CPU
• Only 35 single word instruction to learn
• All single cycle instruction
• Operating speed:DC-20 MHz clock input
DC-200 ns instruction cycle
• Up to 8K x 14 word FLASH Program Memory,
• Up to 368 x 8 bytes of Data Memory (RAM)
• Interrupt capability (up to 14 sources)
2.3.2 Peripheral Features:
• Timer0: 8-bit timer/counter with 8-bit prescaler
• Timer1: 16-bit timer/counter with prescaler,
• Timer2: 8-bit timer/counter with 8-bit period register, • Two Capture, Compare, PWM modules
• Synchronous Serial Port (SSP) with SPI Master mode) and I2C (Master/Slave) • Universal Synchronous Asynchronous...