INTRODUCTION TO IAP

INTRODUCTION TO IAP( In Application Programming)

This is a unique programming technique and a feature provided by latest controllers where the user could program the controller when the application code is under execution.

This gives the user a flexibility to change the value of a variable when the program is executing, and the user can see that the program will take the new modified value from the variable register when-ever it access the variable in the program. There is no need to reset the program.

This needs a dedicated and a very costly hardware. Using this, the user can stop the program execution wherever he needs to check the value of the variable. i.e. the user can debug the program as he likes.

The IAP is not restricted to changing the variable in the program, but user can erase / program the complete flash while the application is running.

Both ISP and IAP needs boot loader software to be inside the controller.

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INTRODUCTION TO ISP

INTRODUCTION TO ISP( In System Programming)

In a simple way, ISP can be defined as a programming concept where the controller is programmed without removing it from the board and without using any external programming device.

ISP needs an UART for programming the controller.

In older systems and 8 bit controllers the user had to carefully remove the controller from the target device and mount it on a separate device called “programmer”, use custom software for the programmer to copy the hex file to the flash of the controller.

In this kind of programming all the external peripheral devices will be non functional at the time of programming the controller.

After the programming is done the controller is reset so that it communicates with the external devices.

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KNOWING THE NOMENCLATURE OF ARM FAMILY

KNOWING THE NOMENCLATURE OF ARM FAMILY

n      ARM-XYZ  TDMI  EJF- S

X -  series of ARM processor

Y -  Support of CACHE MEMORY

Z – Support of Memory management and Memory protection Unit.

T – Thumb architecture Support of 16 bit instruction.

D – Debugger support

M – Fast Multiplier

I – Embedded ICE - In Circuit Emulator

E – Embedded Trace Macro-cell.

J – Jazelle Instruction set / Java byte code, support to java programs

F – Floating point co-processor

S – Synthesizable version means the ARM is a set of software instruction engine that can be compiled on a suitable compiler.

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DEFINE INTERRUPT

DEFINE INTERRUPT
Asynchronous  interrupt, which diverts the attention of the CPU. called interrupt.

If CPU have only one work, then C.P.U. will give the deterministic delay but it can't possible because C.P.U. has a lot of work like it controls the entire unit of C.P.U.

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INTRODUCTION OF BLUETOOTH

Introduction of Bluetooth
Bluetooth is a low-power,short-distance radio technology, originally developed as a cable replacement to connect devices such as mobile phone handsets,headsets and portable computers. Bluetooth uses frequency spectrum in the range of  2400 MHz to 2483.5 MHz. Bluetooth allows both time critical data communication like voice and audio,as well as high speed,time insensitive packet data communication. Data rate via Bluetooth connection can be up 723.2 kbps. Each Bluetooth device has a unique-48-bit IEEE MAC address known as the Bluetooth device address (BD-ADDR) that is used to identify a Bluetooth device. This address cannot be easily changed by the end-user.Because Bluetooth is designed for low-powered portable applications, the radio power must be minimized.
           Files can be transferred between two Bluetooth devices using OBEX (Object Exchange) file transfer. OBEX is binary protocol designed to allow a variety of devices to exchange data simply and spontaneously. Briefly, OBEX defines a session protocol that is used to send request from a client to a server. The server replies with responses.When one Bluetooth device wants to download files from another Bluetooth  device, it first searches if the other device is in range. On success, a Bluetooth connection will be set up between two devices.After the connection is set up, the file can be transferred from source to destination by using OBEX protocol if in both devices OBEX is implemented. The Bluetooth radio is the lowest of  Bluetooth communication.
           Bluetooth devices are divided into three power classes; the only difference between them is the transmission power levels used. Table 1.1 summarizes their differences among the power classes of Bluetooth. Almost all Bluetooth-enabled cell phones,headsets,laptops,and other consumer-level Bluetooth devices are class 2 devices. There are many class 1 USB devices for sale to consumers. It is the higher class that determines the properties. If a class 1 USB device communicates with a class 2 Bluetooth cell phone, the cell phone limits the range Bluetooth radio. Class 3 Bluetooth device are rare, as their limited range heavily restricts their usefulness.

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BASICS OF ZIGBEE AND BLUETOOTH

BASICS OF ZIGBEE AND BLUETOOTH

ZIGBEE:

The name ZIGBEE is said to come from the domestic honeybee,which uses a zigbee type of dance to communicate important information to other hive member.
ZIGBEE technology is a low data rate, low power consumption, low-cost, wireless networking protocol targeted towards automation and remote control applications.

BLUETOOTH:

Bluetooth aims at connectivity of mobile devices in close. It uses higher data rates,higher power consumption on large packet-device.
In Bluetooth, the network range is small and its longer join time is detrimental(3-sec).
Bluetooth has a network range of 1 to 10 meters and has a protocol stack size of 250 kilo-byte and its batteries are rechargeable.

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INTRODUCTION OF UNIVERSAL ASYNCHRONOUS RECEIVER/TRANSMITTER(UART)

INTRODUCTION OF UNIVERSAL ASYNCHRONOUS RECEIVER/TRANSMITTER(UART)

-- It is a piece of computer n/w,that translate data between parallel & serial forms.
-- UARTS are commonly used in conjuction with communication standards such as RS-232,
    RS-422,RS-485.
-- A UART is usually an individuals integrated circuit used for serial communication over a 
    computer or peripheral device serial port.UART is commonly included in microcontroller.
-- UART is a Asyncronous & it is full duplex.
  

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BASICS OF ANALOG TO DIGITAL CONVERTER

BASICS OF ANALOG TO DIGITAL CONVERTER

In lot of embedded systems, microcontrollers needs to take analog inputs.Most of the sensors and transducers such as temperature,humidity,pressure are analog.
For interfacing these sensors to the microcontroller,we requires to convert the analog output of these sensors to digital,so that the controller can read it.
One of the most commonly used ADC is ADC0808.ADC 0808 is a successive apporximation type with 8-channels.i.e it can directly access 8 single ended analog signals.

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VECHILE STATUS CONTROL IN MODERN TIME

VECHILE STATUS CONTROL

In day to days life ,we forgot to check the status of our vechile and we move outside and if vechile is stopped down than we understand what fault occurs in vechile.
So to over come this problem,what we do is that,we used to find the status of the component like,brake,accelator,light,speed,location of the vechile etc..by using Global Positioning of Satellite system,GSM & CAN.

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INTRODUCTION OF CONTROLLER AREA NETWORK

INTRODUCTION OF CONTROLLER AREA NETWORK

CAN is Invented by Robert Bosch Gmbh in 1980.
--CAN(Controller Area N/W) is a serial communication protocol,which efficiently supports distributed real   time controls with a very high level of security.
--IT is basically for automotive,to reduce the complexcity of wire.
--In Automative electronics,connected using CAN with bit-rates up to 1Mbps.
--The Intension of this specification is to achieve compatibility between any two  CAN implementations.
--It is a Asynchronous serial bus.
--Here node addressing is absence.
(a) Message Identifier specifies contents & priority.
(b) Lowest message identifier has highest priority.
(c) Multi-master/Broadcasting concept.
(d) Sophisiticated error detection & handling system,
(e) Industrial & Automotive applications.

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WIRELESS SENSOR NETWORK BASED STREET LIGHT MANAGEMENT SYSTEM FOR ENERGY CONSERVATION (ALSO INCLUDES CENTRALISED MONITORING SYSTEM).

WIRELESS SENSOR NETWORK BASED STREET LIGHT MANAGE

This project includes centralized monitoring system where in we can monitor each and every units i.e., street lights which can be monitored by the unit called the server. here street lights can be managed wirelessly using the technology called zigbee.The information of each and every unit can be obtained to the server by GPRS or GSM technoligies.Automated intelligent adaptive street lighting at each pole optimizes lighting levels while saving energy.

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Basic Introduction of CISC & RISC for Embedded Engineers

Sr.No 1	CISC Founded in 1970’s	RISC Founded in late 1980’s
2	Needed more number of clock cycles	Designed to work with less or limited number of clock cycles. Usually 1 clock.
3	These had slow memories coupled to processor built using many simple IC’s.	Could be coupled with faster memories
4	The processor was controlled by microcode ROM’s, which were faster than processor.	The processor itself was faster and interfacing other interface did not much affect the overall speed.
5	Code can execute X86 machines code	Code cannot execute code for X86
6	Older CISC did not support pipeline	Supports pipelining
7	Variable Instruction length	Fixed instruction length.
8	Allows value in memory to be used as operands for data processing	Can work only if data is in registers and not in memory directly.(LOAD & STORE )
9	Have very good code density	Have very poor code density.
10	Hardware complexity is less	Hardware complexity is more.

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