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+# Interrupt and Exception Handling
+
+This chapter describes the interrupt and exception-handling mechanism on a
+Vertex-32 or Vertex-64 processor.
+
+## Interrupts Overview
+
+Interrupts and exceptions are events that get triggered either upon a special
+condition or when the instruction `INT interrupt_number` is executed. Typically,
+an interrupt forces a transfer of execution from the currently executing task to
+a special routine called an interrupt handler or an exception handler. The
+action taken by a processor in response to an interrupt is referred to as
+servicing or handling the interrupt or exception.
+
+Interrupts can occur at regular intervals or randomly during the execution of a
+task or software routine in response to signals from hardware, such as requests
+from peripheral devices. Interrupts can also be generated by software by calling
+the `INT` instruction.
+
+Exceptions occur when the processor detects an error condition while executing
+an instruction. For instance, the processor could detect that a program is
+requesting a page that is currently not mapped, generating a page fault.
+
+When an interrupt is received, the currently running task is suspended while the
+processor services the interrupt or exception. Upon completion of the interrupt
+handler, execution is returned to the suspended task without loss of continuity.
+If the exception cannot be handled or the exception handler does not return, a
+double fault is generated. If a further exception is encountered while servicing
+the double fault, it is considered an unrecoverable error and the processor is
+reset.