KOKILA Embedded Systems 2 Marks Qp

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ANNAI MATHAMMAL SHEELA ENGINEERING COLLEGE

DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING

EMBEDDED SYSTEM

TWO MARKS QUESTIONS WITH ANSWERS

IV YEAR - A & B

Prepared by: S. Kokila AP / ECE

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TWO MARKS QUESTIONS WITH ANSWERS

EMBEDDED SYSTEM

UNIT-I

1. What is an embedded system? An embedded system is one that has computer-hardware with software embedded in it as one of its most important component. It is a computing device that does a specific focused job.

2. What are the components of embedded system?An embedded system has three main components

i) Hardwareii) Softwareiii) Real Time Operating System(RTOS)

What are the classifications of embedded systems?iv) Small scale embedded systemv) Medium scale embedded systemvi) Sophisticated embedded system

3. What are all the application areas of the embedded systems?i) Consumer Appliancesii) Office Automationiii) Industrial Automationiv) Medical Electronicsv) Computer Networkingvi) Telecommunicationsvii) Wireless Technologiesviii) Instrumentationix) Securityx) Finance

4. What are the categories of embedded system? Based on functionality and performance requirements, embedded systems can be categorized as :

i) Stand-alone embedded systemii) Real-time systemsiii) Networked Information Appliancesiv) Mobile Devices

5. What are the special features of embedded systems?i) They do a very specific taskii) They have very limited resourceiii) They work against some deadlinesiv) They are constrained for powerv) They need to be highly reliable

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6. What is stand-alone embedded system?Stand-alone systems work in stand-alone mode. They take inputs, process them and produce the desired output. The input can be electrical signals from transducers or commands. The output can be electrical signals to drive another system.

7. What is real-time system?Embedded systems in which some specific work has to be done in a specific time period are called real-time systems. For example, consider a system that has to open a valve within 30ms when the humidity crosses a particular threshold.

8. What are all the specialities of embedded systems?i) Reliabilityii) Performanceiii) Power consumptioniv) Costv) Sizevi) Limited user interface

10. What are the CPU processors used in embedded system? i) General purpose processor(GPP) ii) Digital signal processor

11. What are the three types of architectures for the processor? i)Von Neumann Architecture ii)Harvard Architecture iii)Super Harvard Architecture

12. What is the Von Neumann Architecture?This Architecture has one memory chip which stores both instruction and data. The processor interacts with the memory through address and data buses to fetch instructions and data.

13. What is Harvard Architecture?It has separate memory blocks, one is program memory and the other is data memory. Program memory stores only instructions and data memory stores only data.

14. What is Super Harvard Architecture(SHARC)?In which the data memory is accessed more frequently than the program memory.Therefore in SHARC provision has been made to store some secondary data in the program memory to balance the load on both memory blocks.

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15. Differentiate CISC and RISC processor?

CISC RISC

i)Complex instruction set computer

ii)It has large instruction set.

iii)It needs less memory

iv)In which software architecture is simple, hardware architecture is complex.

i)Reduced instruction set computer

ii)It has limited number of instruction set

iii)It needs large memory

iv) )In which hardware architecture is simple, software architecture is complex

16. What are the types of memory?i) Program Memory

It stores the firmware permanently.ii) Data Memory

It contents are erased when power is switched off.

17. What are the classifications of memory chip?i) RAMii) ROMiii) Hybrid Memory

a) EEPROMb) Flash memoryc) Non volatile Memory

18. What is ROM?A ROM that locates the following in its ROM-Embedded software, initial data and strings and operating systems or RTOS.

19. What is RAM?This is a Random Access Read and Write memory that the processor uses to store program and data that are volatile and which disappear on power down or off.

20. What is timer?A unit to provide the time for the system clock and Real-Time operations and scheduling.

21. What is watch dog timer?A timer with timeout from which resets the processor in case the program gets stuck for an unexpected time.

(OR)An important timing device in a system that resets the system after a pre-defined timeout. This time may be definable within the first few clock cycles after reset.ss

22. What is clock?Fixed frequency pulses that an oscillator circuit generates and that controls all operations during processing and all timing references of the system. Frequency depends on the needs of the processor circuits. A processor, if it needs 100MHz

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clock then its minimum instruction processing time is a reciprocal of it, which is 10ns.

23. What is compiler?A program that, according to the processor specification, generates machine codes from the high level language. The codes are called object codes.

24. What is Assembler?A program that translates assembly language software into the machine codes placed in a file called ‘.exe’(Executable) file.

25. What is linker?A program that links the compiled codes with the other codes and provides the input for a loader or locator.

26. What is loader? It is a program that reallocates the physical memory addresses for loading into the system RAM memory. Reallocation is necessary, as available memory may not start from 0x0000 at a given instant of processing in a computer. The loader is a part of the OS in a computer.

27. What is locator?It is a program to reallocate the linked files of the program application and the RTOS codes at the actual addresses of the ROM memory. It creates a file in a standard format. File is called ROM image.

28. What is device driver?ISR softwarem,which runs after the programming of the control register of a peripheral

device and to let the device get the inputs or outputs. It executes on an interrupt to or from the device.

29. What is device Manager?Software to mange multiple devices and drivers.

30. What is kernel?A program with functions for memory allocation and deallocation,tasks scheduling, inter-

process communication ,effective management of shared memory access by using the signals ,exception handling signals,semaphores,queues,mailboxes,pipes,i/o management,interrupt controls,device drivers and device management.

31. What is RTOS?OS softwares for rel-time programming and scheduling, process and memory

manager,device driver, device management and multitasking.

32. What is system?A way of working, organizing or doing some task or series of task by following the fixed

plan, program and set of rules.

33. What is processor?

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A processor implements a process or a processes as per the command(instructions)given to it.

EMBEDDED SYSTEMS

UNIT – II

PROGRAMMING FOR EMBEDDED SYSTEMS

1. What are integer data types available in the C programming Language?

2.

List the four fields of a line of code in assembly language. (i) Label field (ii) Operation field (iii) Operand field (iv) Comment field3. What are the situations in which programming are assembly language? (i) Absolute speed is critical, (ii) To access a particular feature of the hardware.4. What are two situations exist to access data in memory? (i) The address of the data is a constant that may be specified by using the identifier that appears in the label foeld where the data is defined in the program. In C, Such data is said to be statically allocated and either declared globally, outside of all functions, or is declared inside a functions, using static keyword.

(ii) The address of the data is a variable that may only be determined at exection time and loaded into a register. In C, any data that is accessed through a pointer, all function parameters and any nonstatic variables declared inside a function must be

Data type Size Range

Unsigned

Char 8 Bits 0 to 255

Short int 16 bits 0 to 65, 535

Int 16or 16 bits: same as unsigned short int;

32bits 32 bits : same as unsigned long int.

Long int 32 bits 0 to 4, 294, 967, 295

Signed

Char 8 Bits -128 to +127

Short int 16 bits -32, 768 to + 32, 767

Int 16or 16 bits: same as signed short int;

32bits 32 bits : same as signed long int.

Long int 32 bits -2, 147, 483,648to +2,147 , 483,647

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accessed in this manner.

5. What are the basic types of memory allocation in C? (i) Static (ii)Dynamic (iii) Automatic

6. What is meant by Automatic memory allocation?

Automatic memory allocation is the default allocation method functions. The key word auto may be added as a declaration prefix to make allocation method explicit.

7. Disadvantages of automatic memory allocation.

(i) The lack of persistence, (ii) An automatis object declared with in the body of a function will not retain its value from one invocation of the function another.

8. Advantages of automatic memory allocation. (i) Conservation of memory through reuse, (ii) The program manages the reuse of this memory resources automatically.

9. Advantages and disadvantages of static allocation. Adv: Persistence values. The objects that are use automatic allocation, a value stored in a static object will remain from one execution of function another. Dis adv: The inability to reclaim the memory for other purposes once the object is no longer needed.

10. What is meant by dynamic allocation? Dynamic objects are allocated from a region of memory known as the heap using the library function malloc. The size of operator is normally used to determine the amount of memory required to hold an object of the desired type.

11. Advantages and disadvantages of Dynamic allocation.

Adv: The advantages of dynamic allocation is that it offers both the persistence of static allocation and memory conservation through reuse.

Dis adv: The disadvantages is the burden it places on the programmer to balance each call to malloc with a corresponding call to free.

12. What is meant by shared function? A shared functions is one that is called by more than one thread; any function called by ashared function is also a shared function. Any static object referenced with in a

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shared function is thus a form of shared memory.

13. What is meant by shared memory?

When two or more asynchronous instruction sequences access the same data, that Data os called shared memory.14. What is meant by fragmentation? The scattering of parts of a computer file across different regions of a disk. Fragmentation occurs when the operation system breaks up the file and stores it in Locations left vacant by previously deleted files. The more fragmented the file, the Slower it is to retrieve each piece of the file must be identified and located on the Disk.15. Define reentrant function. A function is reentrant if, while it is being executed, it can be re – invoked by itself, or by any other routine, by interrupting the present execution for a while.16. What are the two location of declarations are usually placed? (i) Outside of all functions to create global variables, (ii) Immediately following a function header to create temporary variable Local to the function.17. What are C Register Usage Conventions for the DJGPP Complier? (i) The memory address that contains the instruction, (ii) Fetching the instruction from memory, (iii) Executing the instruction

18. What are the different software coding styles available in the case of embedded Systems? (i) Machine codes, (ii) Assembly language, (iii) High level Language19. What the three distinct phases that constitute the sequencing of an instruction are determine?

Register (s) Usage in C functionsEAX Function return all pointer and integer values up to 32

bits in this register.EDX and EAX Functions return 64 –bit values (long long ints) in this

register pair.

EBP Used to access (i) The arguments that were passed to a function when it was called ii) Any automatic variables allocated by the function

EBX, ESI, EDI < EBP, DS, ES< and SS

These registers must be preserved by functions written in assembly language any of these registers that the function modifies should be pushed on entry to the function and popped on exit.

EAX, ECX, EDX, FS and GS

“Scratch” registers. These registers may be used without – preserving their current content.

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EMBEDDED SYSTEMS

UNIT IIIHARDWARE PLATFORM

1) What is Microcontroller?Microcontroller is a device, which allows controlling the timing and sequencing of these machines and processes.

2) What is meant by PIC Microcontroller?

Peripheral Interface Controllers (PIC) is a family of microcontrollers. PIC microcontrollers are RISC processors and use Harvard architecture.

3) What is data and program memory?The data memory of PIC is 8-bit wide, whereas the PIC program memory is 12-,14-, or 16- bit wide. Data memory stores only data and program memory stores instruction and data.

4) What are all the CPU registers available in PIC?i) W or Working Reg ( 8 bits ) ii) STATUS Reg ( 8 bits )iii) FSR ( File Selection Register)iv) INDFv) PCLATH (Program Counter Latch)vi) PCL(Program Counter Low Byte)

5) What is W Register ?W, the working register is 8-bit wide. It contains one of the source operands during the execution of instructions and may serve as the destination for the result of the operation. W register is only used for ALU operations and is not an addressable register.

6) Draw the bit representation of STATUS register ?

0 0 RPO TO PD Z DC C

7) What is carry bit(C)?When two 8-bit operands are added, a 9- bit result can occur, because the result of addition may exceed 256(FFH). The 9th bit is copied in the carry bit.

8) What is Digital Carry (DC)? This bit indicates a carry from the lower 4 bits, during 8-bit addition. If set, it means there is a Carry from the 3rd bit to the 4th bit position.

9) What is Zero bit (Z)?Many arithmetic & logic instructions affect the zero flag. For example, decf instruction can be used to decrement a variable in RAM, and if the result is zero, Z-bit is set. All the instructions do not affect the Z flag. For example decfsz & incfz.

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10) What is FSR?File Selection Register is the pointer used for indirect memory addressing in whole register file. It must be noted that, in PIC, ever instruction that can be used for direct addressing may also be used in a different way for indirect addressing.

11) What is INDF?INDF stands for Indirect through FSR. This is not a physical register. Addressing INDF register will cause indirect addressing. INDF register actually accesses the register pointed by the FSR.

12) Write a program to clear the RAM location 20H.Movlw 0x20H ; Initialize pointer to RAMMovwf FSR ; clrf INDF ; Clear INDF register

13) What is PCLATH?Program Counter Latch can be independently read or written like any other registers. PCLATH from the program counter and is a separate entity. Any write to PCL will cause the contents of PCLATH to be transferred to the 13-bit program counter higher locations.

14) What is PCL?PCL is the lower byte of the program counter. The PIC program counter is 13-bit wide. It can be read like any other registers. A write to PCL causes PCLATH contents to be transferred to program counter higher bit locations, automatically.

15) What are the different PIC reset actions ?i) Power – on – resetii) MCLR reset during the normal operationiii) MCLR reset during SLEEP modeiv) Watchdog timer reset during normal operation

16) What is Power-on Reset(POR)?MCLR IS THE MASTER CLEAR PIN , WHICH WHEN MADE LOW CAUSES PIC to reset. A POR pulse is generated when VDD rise is detected.The range of VDD through which it should raise is from 1.5 to 2.1 V.

17) What are the devices support BOR?PIC 16C66 and 16C74 support brown-out-reset.

18) What is BOR?Brown-Out-Reset takes place when the supply voltage falls bellow 4V. The device remains in the BOR condition till the power supply voltage is restored.

19) What are the different PIC clock ?

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PIC can have four different methods of clock, namely, external RC, internal RC, crystal and external clock.

20) What are the PIC memory organization?i) Program memoryii) Data memory

a) Register File Structureb) OPTION Registerc) INTCON Register

21) Draw the bit representation of OPTION Register.

22)Draw the bit representation of INTCON register.

23)Write the program to load the working register.Movlw B ‘00000001Addwf H ’12,w

22) What is a direct addressing mode?Direct addressing modes uses 7 bits of the instruction and the 8th bit from RPO bit. If RPO bit

is ‘0’ then accessed location is from bank 0, otherwise the location from bank 1 is accessed.23) What is indirect addressing?

In indirect addressing, the 8-bit address of the location in register file to be accessed is written in file selection register (FSR) and the instruction that uses 00H as the direct address, which is INDF , result into indirect addressing.24) How many I/O Ports are there in PIC16C61?

PIC 16C61 and 16C71 has 13 I/O lines. PORTA pins are RA0, RA2, RA3, and RA4; whereas PORTB is an 8-bit port with corresponding I/O lines RB0 to RB7.25) What are the interrupts in PIC 16C61/71?

i) External interrupt INT( INTF,INTE)ii) Timer 0 interrupt (TOIF,TOIE)iii) PORTB change interrupt (RBIF,RBIE)

26) What is External interrupt?INT is the interrupt due to external source. A transition at pin RB0/INT causes this interrupt. This is an edge-sensitive interrupt.

27) What is timer 0 interrupt?Timer 0 overflow interrupt is generated when counter/timer 0 overflow from 0FFH to 00H.

This will set the TOIF flag in INTCON.

28) What is PORTB Change Interrupt?A change from high to low or low to high on PORTB pins RB4 to RB7 causes this interrupt .

It is possible to have PORTB change interrupt, if pins RB4 to Rb7 are configured as inputs.29) What is ADC interrupt?

This interrupt is generated when the analog to digital conversion ends. This is only applicable to 16C71 or 16C7X parts in general. ADIE is the bit that enables this interrupt in INTCON.

INTEDG

RTS RTE PSA PS2 PS1 PS0

GIE ADIE TOIE INTE RBIE TOIF INTF RBIF

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UNIT IV EMBEDDED TWO MARKS

1.What are the kernel objects? Tasks Task scheduler Interrupt service Routines Semaphores Mutexes Mailboxes Message queues Pipes Event Registers

2.What are embedded tasks? Operating system Tasks Application- specific Tasks

3.What are the kernel tasks and give its priority. Startup task -which is executed when the operating system starts Exception handling task -to handle the exceptions Logging tasks -to log the various system messages Idle task -which will have the lowest priority and will run there is no other task to

run- This task ensures that the CPU is not Idle

4.Define Task scheduling.A mechanism for deciding which task will get CPU time next has to worked out. This is

known as task scheduling. 5.Define Reentrant function. A function that can be used by more than one task without data corruption is called reentrant function.

6.Define non-reentrant Function.If data is corrupted when more than one task calls the function ,such a function is

non-reentrant function

7.What are shared resources? Resources shared by two or more tasks are called shared resources. Example :Serial port, keyboard. Two tasks may like to send the data to the display.

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8.What is Intertask communication?Task may need to communicate data amongst themselves. For instance, a task writes

data into an array and another task to read the data from that array.

9.What are the task states? Running Waiting Ready –To-Run

10.What is Running state?A task is said to be in running state if it is currently being executed by CPU.

11.What is waiting state?A task is said to be in waiting state if it is waiting for another event to occur.

12.What is Ready-To-Run state?

A task is said to be in Ready-To-Run state if it is waiting in the queue for the CPU.

13.What is Task stack?Every task will have a stack that stores the local variables ,function parameters

,return addresses and CPU registers during an interrupt. At the time of creating a task ,the size of the task has to be specified or a default stack size has to be used.

14.What is context switching?The state of the CPU registers when a task is pre-empted is called the context.

Savingtheconents of CPU registers and then loading the new task is called context switching.15.What are Scheduling Algorithms?

First In First Out Round-robin algorithm Round-robin with priority Shortest job first Non-preemptive multitasking Preemptive multitasking.

16.What is First In First Out?

In First In First Out scheduling algorithm the task which are ready to run are kept

in a queue and the CPU serves a task on first-come-first served basis.

Task 1 Task 4 Task 2 Task 3

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17.What is Round-robin Algorithm?In the round robin algorithm the kernel allocates a certain amount of time for

each task waiting in the queue The time slice allocated to each task is called quantum.

Task 1 Running

Task 2 Running

Task 3 Running

Task 1 Running

Task 2 Running

Task 3 Running

18.What is round robin with priority?The round robin algorithm (allocates a certain amount of time for each task waiting in

the queue )can be slightly modified by assigning priority levels to some or all the tasks A high priority task can interrupt the CPU so that it can be executed This Scheduling algorithm can meet the desired response time for a high priority task.

19.What is Shortest-job first?The time for each task can be estimated and the CPU can execute the task which takes

the least amount of time.

20.What is meant by kernel?A basic unit of any OS that includes functions for processes, memory, task scheduling,

inter process communication, management of devices, IOs and interrupts and may include the file systems and network subsystems in certain OSs.

21.What is meant by Operating System?A system having kernel functions, file management functions and other functions also.

22.What is meant by Real Time Operating System? Operating System with real time task scheduling, interrupt-latency control, synchronization of task with IPCs, predictable timing and synchronization behavior of the system.

23.What is meant by task?A task is for the service of Specific actions and may also corresponds to the codes, which

execute for an interrupt. A task is an independent process that takes control of the CPU when scheduled by a scheduler at an OS. Every task has a TCB.

24.What is meant by task state?A state of a task that changes on scheduler directions. A task at an instance can be in one

of the states,waiting, ready to run and running that are controlled by the scheduler.

25.What is meant by shared data problem?If a variable is used in two different processes(tasks) and another task if interrupts

without before the operation on that data is completed, the operation on that data then the shared data problem arises.26.Define Semaphores.

I. It is used to perform both task synchronization and resource synchronization

II. A Special variable (or functions) used to take note of certain actions to prevent another task or process from proceeding.

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27.Define Mutex .(It stands for Mutual Exclusion)It is used to perform both task synchronization and resource synchronizationA special variable used to take note of certain action to prevent any task or

process from proceeding further and at the same time let another task exclusively proceed further. Mutex helps in exclusion of one task with respect to another by a scheduler in multitasking operations.

28.What is meant by counting Semaphore?A semaphore in which the value of which can be incremented and decremented

and which is not a Boolean variable.

29.Define Message Queue.A task sending the multiple FIFO or priority messages into a queue for use by

another task using queue messages as an input.

30.Define Mailbox.A message or a message pointer from a task that is addressed to another task.

31.Define Pipe.One task sends the messages through pipe and another task uses this as input. i.e.

output of first task is given as input to the second task. A pipeline can be a device like file which is also a virtual device.$cat hello.c | more

32.What are the Rate Monotonic assumptions? a)Highest priority task will run first, i.e the priority based preemptive multitasking is the scheduling algorithm. b)All the task run at regular intervals. i.e the tasks are periodic. c) Tasks do not synchronise with each other. i.e they do not share resources or share data(which is not a valid assumption).

33.Define Static Priority Assignment.Static Priority assignment,a task will be assigned a priority at the time of creating the task

and it remains the same.

34.Define Dynamic Priority Assignment.Dynamic priority assignment, the priority of the task can be changed during execution

time.

35.What are the Management function calls? Create Delete Suspend Resume Change priority Query

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36.Define Interrupt Latency.The maximum time for which interrupts are disabled + Time to start the execution of the

first instruction in the ISR is called interrupt latency.

37.Define Interrupt Response Time.Time between receipt of interrupt signal and starting the code that handles the interrupt

is called interrupt response time.

38.Define Interrupt Recovery time.Time required for CPU to return the interrupted code/highest priority task is called

Interrupt recovery time.

39.How can we achieve Mutual exclusion?Mutual; exclusion can be achieved through the following mechanisms

Disabling the scheduler Disabling the interrupts By test and set operations Using Semaphores

40.Define Priority Inheritance.In priority inheritance, the priority of the task which acquired the mutex will be

increased to a value higher than the priority of the task competing for that resource.

41.Define Priority inversion problem.The high priority task has to wait for a very long time, inspite of its high priority due to

the semaphore held by the LP task. This problem is called the Priority Inversion problem.

42.How memory is managed?The memory manager manages i)use of a memory address memory space by a process,ii)specific mechanisms to share the memory spaceiii)specific mechanisms to restrict sharing of a given memory space andiv)optimisations of the access periods of a memory.

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UNIT V EMBEDDED TWO MARKS

REAL – TIME OPERATING SYSTEM TOOLS AND CASE STUDIES

1. What is RTOS?RTOS has the basic functions of the os plus functions for Real time task

scheduling and interrupt latency control. RTOS uses the timers and system clocks, time

allocation and de - allocation to attain best utilization of the CPU time.

2. What are the types of RTOS?

In – house developed RTOS, Board – based commercial RTOS, General purposes

OS with RTOS.

3. Define RTOS μCOS – II?

One popular RTOS for the embedded system development is μCOS – II. For non

– commercial use, RTOS μCOS – II is also a freeware. Its name μCOS –II is derived

from Microcontroller operating system. It is also popularly known as MUCOS or Micro

COS or MUCOS.

4. What are the two source available for μCOS – II?

1) Processor – dependent source files,

2) Processor – independent source files.

5. List out any 6 features of μCOS – II?

1) Scalable

2) Portable

3) Interrupt management

4) Romable

5) Interrupt services

6) Deterministic

6. List out functions of μCOS – II?

1) System level functions,2) Task service and time functions,3) Time delay functions,4) Memory allocation related functions,5) Semaphore related functions,6) Mailbox relaxed functions,7) Queue related functions,

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7. What are the mailbox services provided by the kernel?1) Initialize the contents of a mailbox. The mailbox initially might or might not Contain a message into the mailbox.2) Deposit a message into the mailbox (POST), 3) Wait for a message to be deposited into the mailbox (PEND),4) Get a message from mailbox, if one is present, but do not suspend the caller if the mailbox is empty (ACCEPT). If the mailbox contains a message; the message is extracted from the mailbox.

8. Functions of signal ISR?1) Call task restart (),

2) Call exit (),3) Call long jump ()

9. What is message mailbox?Message can be sent to a task through kernel services. A message mailbox exchange is

typically a pointer – size variable. Through a service provide by the kernel, a task or an ISR can deposit a message (the pointer) into the mailbox.

10. List out any goals of μCOS – II?1) Use message and queues for task communication,2) Use event flag for task synchronization,3) Handling interrupt and shared resources,4) limit priority inversion,5) Prevent deadlock

11. What is the specifications of automatic chocolate vending machine?1) It has an alphanumeric keypad on the top of the machine,2) It has a three – line LCD display unit on the top of the machine,3) It has a coin – insertion slot. So that the child can insert the coin to buy a Chocolate of his/her choice,4) It has a delivery slot. So that the child can collect the chocolate and coin if refunded,5) It has an internet connection port. So that the owner can known the status of the ACVM sales from a remote location.

12. What is the purpose of Smart Card?Enabling authentication and verification of card holder by a host and enabling GUI at host machine to interact with the card holder / user for the required transactions; for example, financial transactions with a bank of credit card transactions.

13. What is class diagram?A class diagrams shows how the classes and objects of a class relate, and also hierarchical associations and object interaction between the class and object.

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14. What is state diagram?A state diagram shows a model of a structure for its start, end, in – between associations through the transactions and shows event labels with associated transitions.

15. What is synchronization diagrams?The synchronization objects near the line connecting task with another task. The synchronization objects is a semaphore or mailbox messages for notification.

16. What is the system Functioning?The card inserts at host machine. The radiations from the host activate a change pump at

card. The charge pump powers the soC circuit, Which consist of card processor, memory, timer, interrupt handler and port _ IO.On power up ,system reset signals. Task_PW sends through port_IO.The task-Appl then runs API17. What is the Purpose of Adaptive Cruise Control?

Adaptive control is used to Controll the cruising of car,ie for controlling the speed of the car and inter – car distance.18.What are the inputs Required for ACC?

i) Present alignment of rader (or laser) beam emitter.ii) Delay interval in reflected pulse with respect to transmitted pulse from emitter.iii) Throttle position from a stepper motor position senor.iv) Speed from a speedometer.v) Brake status for brake activites from brake switch and pedal.

19. List out of some function of the ACC system?1) When battery power becomes low, the ACC system deactivitates after issuing alarm

and flashing messages, 2) The differences of d with respect to safe dsafe and present distance dset are cyclically

estimated. Task range does this function,3) The speedometer measures the speed and error in present speed and measured speed

is also periodically estimated, task speed does this function.20. What is ACC?

Adaptive cruise control or autonomous cruise control or active cursive control or intelligent cruise control system is commonly used in activation electronics and defense aircrafts for cruising since long.

21. What is the automotive embedded system based control uses in microcontroller?Speedometer,1) Stepper motor based alignment unit,2) Stepper motor based throttle control unit;3) Transceiver for transmitting pluses through an antenna hidden under the plastic

plates.

22. List of tasks?Reset task (), Task_read port (), Task_ pw (), Task_appl (),

23. What is kernel?The kernel is the essential center of a compute os, the code that provides basic services for all other parts of the os.

*****

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