Embedded

Explain what is semaphore?

A semaphore is an abstract datatype or variable that is used for controlling access, by multiple processes to a common resource in a concurrent system such as multiprogramming operating system. Semaphores are commonly used for two purposes To share a common memory space To share access to files

Explain what is a Watchdog Timer?

A watchdog timer is an electronic device or electronic card that execute specific operation after certain time period if something goes wrong with an electronic system.

Explain what is embedded system in a computer system?

An embedded system is a computer system that is part of a larger system or machine. It is a system with a dedicated function within a larger electrical or mechanical system.

Explain what is the need for an infinite loop in embedded systems?

Embedded systems require infinite loops for repeatedly processing or monitoring the state of the program. For instance, the case of a program state continuously being verified for any exceptional errors that might just happen during run-time such as memory outage or divide by zero, etc.

Mention what are the essential components of embedded system?

Essential components of embedded system includes Hardware Processor Memory Timers I/O circuits System application specific circuits Software It ensures the availability of System Memory It checks the Processor Speed availability The need to limit power lost when running the system continuously Real Time Operating System It runs a process as per scheduling and do the switching from one process to another

Mention what are buses used for communication in embedded system?

For embedded system, the buses used for communication includes I2C: It is used for communication between multiple ICs CAN: It is used in automobiles with centrally controlled network USB: It is used for communication between CPU and devices like mouse, etc. While ISA, EISA, PCI are standard buses for parallel communication used in PCs, computer network devices, etc.

Explain what is interrupt latency? How can you reduce it?

Interrupt latency is a time taken to return from the interrupt service routine post handling a specific interrupt. By writing minor ISR routines, interrupt latency can be reduced.

Mention what is the difference between microprocessor and microcontroller?

Microprocessor is managers of the resources (I/O, memory) which lie outside of its architecture Microcontroller have I/O, memory, etc. built into it and specifically designed for control

List out various uses of timers in embedded system?

Real Time Clock (RTC) for the system Initiating an event after a preset time delay Initiating an even after a comparison of preset times Capturing the count value in timer on an event Between two events finding the time interval Time slicing for various tasks Time division multiplexing Scheduling of various tasks in RTOS

Explain what are real-time embedded systems?

Real-time embedded systems are computer systems that monitor, respond or control an external environment. This environment is connected to the computer system through actuators, sensors, and other input-output interfaces.

List out some of the commonly found errors in Embedded Systems?

Some of the commonly found errors in embedded systems are Damage of memory devices static discharges and transient current Address line malfunctioning due to a short in circuit Data lines malfunctioning Due to garbage or errors some memory locations being inaccessible in storage Inappropriate insertion of memory devices into the memory slots Wrong control signals

Mention how I/O devices are classified for embedded system?

The I/O devices of embedded system are classified into two categories Serial: Synchronous : Input: Audio/Video signal Output: Audio/Video signal Asynchronous : Input: Keypad, Mouse, Modem Output: Printer, Modem Parallel

Explain what is microcontroller?

The microcontroller is a self-contained system with peripherals, memory and a processor that can be used as embedded system.

Why embedded system is useful?

With embedded system, it is possible to replace dozens or even more of hardware logic gates, input buffers, timing circuits, output drivers, etc. with a relatively cheap microprocessor.