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1. Prepare a report similar like an Assignment2. The format for the same is already discussed in the class3. submit the earliest by 3rd November 2008.
Microsoft X-Box 360 HDMI 20GB Gaming Console 05BCE187, 223, 229, 219, 193, 04BCE127 (D Sec)1st Batch – 05BCE133, 155, 145, 153, 130 (C Sec)2nd Batch – 05BCe159, 158, 152, 146, [...]

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Virtual Sockets

Tasks or section of Tasks can communicate with another task or section of task
The tasks may send or receive the stream of bytes or datagram to communicate with each other
It is similar like IP Address / Port.
In the above diagram, Task C in the Task Set is communicating with Task D in the Same [...]

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Pipes are similar like message queues
A pipe can be opened or closed similar like a fopen() and fclose() of a C Program
A Task can write through a scheduler to a pipe at the back pointer address (*pBACK)
A Task can read through a scheduler to a pipe at the front pointer address (*pFRONT)

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Mailboxes

A Meassage mailbox is an IPC message Block that can be used only by a single destined Task

The source is the task that sends the message pointer to a created mailbox.

Example is the Mobile phone LCD Multiline display task in which the time and list of phone number displayed on a single display
There are [...]

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Elimination of Shared Data Problems or Problems with Semaphores
The use of semaphores does not eliminate the shared data problem completely.
So there are some problems when using semaphores

Sharing of two semaphores leads to deadlocks
Suppose that the locked semaphore is not released? There should be some timeout interval in which after the timeout the Watch Dog Timer [...]

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In the above Diagram,

The Task A Requesting for taking semaphore with the Kernel or Operating System
The kernel acknowledge and ask task A to take the semaphore
During that time Task B is Blocked (which also uses the same semphore)
Task A Releases the semaphore, Event to the OS
Task B starts running by taking the semaphore

Use of [...]

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Assume that several ISRs or tasks share a variable. If there is a variable currently running under a task and there is an interrupt and some other task will be taking the control of that variable. Since the variable is already used by other task, so there comes a shared data problem.The bugs encountered in [...]

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Message Queues

Either one task or group of tasks can use the queue
Usually queue is circular. elements are accessed by means of FIFO.
Printer task is an example

Queue

Initialization before using the function
provision for multiple queues. each queue will be having an ID
size of the queue is either user defined or predefined by the scheduler
There may be a [...]

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Signals

Signal is a short message sent from a process for enabling inter process communication
Signal is usually a one bit output comes from a process
signal takes a shortest possible CPU time unlike Semaphores.
Signals are useful for handling exceptions
Whenever there is an error during a running of process, a signal is generated thereby the scheduler schedules a [...]

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Interprocess Communication (IPC)A process (task or ISR) generates an input information by setting or resetting a flag or value or generates an output, which will be used by some other process.
Various techniques behind IPC are

Signals
Semaphores (Counting semaphore or binary semaphores)
Message Queues, Mailboxes and Pipes
Virtual Sockets
Remote Procedure calls (RPC) for distributed Processes

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