Interrupts

What is an interrupt?

A signal sent to the processor that is sent by another component requesting attention form the processor.

How is an interrupt recognised?

A change in contents of the status register between the Fetch and Decode stages of the FDE cycle

What is the Vectored Interrupt Method?

• The processor stops executing the current program

• Its registers contents is placed onto the system stack

• Loads the interrupt service routine

• Once complete the registers are restored and the previous program is resumed

What is placing the registers contents onto the system stack known as?

Saving the volatile environment

What is the interrupt service routine

A series of instructions for handling a specific interrupt