Trapdoor is a secret undocumented entry point into a program used to grant access without normal methods of access authentication. A trap is a software interrupt, usually the result of an error condition.

Fault handlers are also an interrupt handler with an exception that the interrupt handlers cannot sleep. Fault handlers sleep in the context of the process that caused the memory fault. The fault refers to the running process and no arbitrary processes are put to sleep.

SIM is Set Interrupt Mask. Used to mask the hardware interrupts. RIM is Read Interrupt Mask. Used to check whether the interrupt is Masked or not.

In 8086 Carry flag, Parity flag, Auxiliary carry flag, Zero flag, Overflow flag, Trace flag, Interrupt flag, Direction flag, and Sign flag.

An interrupt that can be turned off by the programmer is known as Maskable interrupt.

An interrupt which can be never be turned off (ie. disabled) is known as Non-Maskable interrupt

In 8086 Carry flag, Parity flag, Auxiliary carry flag, Zero flag, Overflow flag, Trace flag, Interrupt flag, Direction flag, and Sign flag.

Three important pieces of information are required to configure the LAN adapter card for use: The interrupt request (IRQ) setting the adapter will use to communicate with the system, the I/O port address the adapter will use to exchange information with the system, and the base memory address that the adapter will use as a starting point in memory for DMA transfers.

When a parity error occurs, a Non-Maskable Interrupt (NMI) signal is co-generated in the system, causing the BIOS to execute its NMI handler routine. This routine will normally place a parity error message onscreen, along with an option to shut down the system or to continue. In other cases, the system will show a short memory count during the POST and lock up without an error message. Another possibility is that the system will count the memory, lock up, and reboot itself. If the memory error occurs higher in the physical memory device, this situation can occur after the operating system and applications have been loaded and started running.

In the course of normal operations, the various I/O devices attached to a PC, such as the keyboard and disk drives, require servicing from the system's microprocessor. Because these service requests can happen at any time and tend to require immediate attention, I/O devices generally have the capability to interrupt the microprocessor while it is executing a program. The I/O device accomplishes this by issuing an interrupt request (IRQ) input signal to the microprocessor.