ISR routine is a special function, called from the main(). True or false?
False.
ISR (Interrupt Service Routine) is a special function that is not called from the main() function. It is typically called by the hardware or software when an interrupt event occurs, such as a timer interrupt or an external signal. The ISR is used to handle the interrupt and perform any necessary tasks before returning control to the main() function.
True. An ISR (Interrupt Service Routine) is a special function that is typically called from the main program in embedded systems or real-time operating systems. It is designed to handle certain interrupts and respond to them in a timely manner. When an interrupt occurs, the main program is temporarily suspended, and the control is transferred to the ISR to handle the interrupt. Once the ISR completes its execution, the main program resumes where it left off.
The answer to your question is: False.
An Interrupt Service Routine (ISR) is a special function that is executed in response to an interrupt event. It is not called directly from the main() function, but rather it interrupts the normal flow of execution to handle a specific event or interrupt request.
To understand how ISR routines work in a microcontroller or a similar system, we need to have a basic understanding of the interrupt mechanism. When an interrupt event occurs, the microcontroller suspends its normal execution and transfers control to the corresponding ISR. Once the ISR completes its task, it returns execution back to the point where it was interrupted.
The main() function in a program is the entry point of the program, and it usually contains the main logic and the main control loop of the application. It is responsible for initializing the system, configuring peripherals, and performing any necessary setup tasks. However, it does not directly call the ISR routines.
In most microcontroller architectures, the interrupts are managed by an Interrupt Vector Table (IVT). The IVT is a data structure that holds the addresses of the various ISR routines. When an interrupt occurs, the hardware uses the IVT to determine the address of the corresponding ISR and transfers control to that routine.
It is the responsibility of the programmer to write the ISR routines and assign them to the correct interrupt source. Typically, this involves setting up the interrupt vector table with the addresses of the ISR routines and configuring the interrupt controller to enable specific interrupt sources.
In summary, an ISR routine is a special function that is executed in response to an interrupt event. It is not called directly from the main() function, but rather interrupts the normal flow of execution to handle a specific event or interrupt request.