What does the CPU do when an interrupt occurs?
When an interrupt occurs, it causes the CPU to stop executing the current program. When it is generated, the processor saves its execution state via a context switch, and begins executing the interrupt handler at the interrupt vector.
How is channel i/o different from interrupt driven I O?
Interrupt initiated I/O. Direct Memory Access (DMA)…Difference between Programmed and Interrupt Initiated I/O :
| Programmed I/O | Interrupt Initiated I/O |
|---|---|
| Its module is treated as a slow module. | Its module is faster than programmed I/O module. |
| It is quite easy to program and understand. | It can be tricky and complicated to understand if one uses low level language. |
What are interrupt driven?
interrupt-driven Denoting a process that is restarted by the occurrence of an interrupt. In an interrupt-driven process some other process is allowed to run, and the device responsible for the auxiliary action is able to signal with an interrupt that it has completed its work.
Which of the following takes over bus control from CPU for I O?
DMA controller
The DMA controller takes over the buses to manage the transfer directly between the I/O devices and the memory unit.
What happens when interrupt is requested?
When an interrupt is acknowledged, the CPU stores in an internal register the priority level of that interrupt. When a subsequent interrupt is received, its priority is checked against the priority register; the new request is acknowledged only if it has higher priority than the currently pending interrupt.
What happens to the interrupt in an interrupt service routine?
An interrupt is a signal to the processor emitted by hardware or software indicating an event that needs immediate attention. Whenever an interrupt occurs, the controller completes the execution of the current instruction and starts the execution of an Interrupt Service Routine (ISR) or Interrupt Handler.
What is interrupt driven I O explain how an I O is serviced?
Interrupt I/O is a way of controlling input/output activity whereby a peripheral or terminal that needs to make or receive a data transfer sends a signal. This will cause a program interrupt to be set. Relative to the total interrupt system, the processors enter an interrupt service routine.
How do IO devices communicate with CPU?
To communicate with a particular device, the processor places a device address on address lines. Each Interface decodes the address and control received from the I/O bus, interprets them for peripherals and provides signals for the peripheral controller.
How does a CPU determine if an interrupt has been raised?
The processor changes to a specific interrupt request mode, which reflects the interrupt being raised. 2. The previous mode’s cpsr is saved into the spsr of the new interrupt request mode.