Chapter 21 Flashcards
What are interrupts
Interrupts in reality are events that occur outside the processor and the processor must be informed about them. Interrupts are asynchronous and unpredictable.
What is meaning of asynchronous for interrupts
Asynchronous means that the interrupts occur, independent of the working of the processor. It has nothing to do with processor state.
What are Synchronous events
Synchronous events are those that occur side by side with another activity.
What are 2 types of interrupts
Software interrupts and hardware interrupts
What are hardware interrupts and hardware interrupts
Hardware interrupts happens outside processor and software interrupts happens inside processor.
What instruction is used to generate the interrupt
INT
What is the name of routine for INT instruction
interrupt service routine
What are vectored interrupts
vectored interrupts meaning that the address of the interrupt routine is not directly mentioned in an interrupt call, rather the address is lookup up from a table.
What is meaning of hooking an interrupt
mapping vector table is called hooking an interrupt
What is interrupt vector table
The correlation process from the interrupt number to the interrupt handler uses a table called interrupt vector table.
What is vector
An entry in interrupt vector table is called vector.
What instruction is used when return from interruption
IRET
What is at physical memory address zero
IVT (interrupt vector table)
What is the size of IVT
1 KB
What is size of one vector
4 bytes
