Final Lecture on Operating Systems: Inputs and Outputs

These flashcards cover key concepts, definitions, and terminology from the final lecture on Operating Systems focusing on Inputs and Outputs.

Input/Output (IO)

The management of device communications and data transfer in a computer system.

Block Device

A type of IO device that stores information in fixed size blocks, each with its own address.

Character Device

A type of IO device that accepts or delivers a stream of characters without regard to block structure.

Device Controller

A chip that physically controls the IO device and accepts commands from the operating system.

Device Driver

Software that allows the operating system to communicate with a hardware device.

Interrupt

An asynchronous event generated by hardware to signal that an IO operation is complete.

Direct Memory Access (DMA)

A method that allows hardware devices to access the main memory without constant intervention from the CPU.

Ports Mapped IO

A scheme where IO registers are accessed via dedicated port numbers.

Memory Mapped IO (MMIO)

A scheme where IO registers are mapped into the same address space as main memory.

Trap

A synchronous interrupt generated by program code to handle exceptions.

Fault

An exception that occurs due to unexpected conditions, usually not deliberate.

Precision of Interrupts

The degree to which interrupts ensure that all prior instructions have been completed and none beyond the interrupt point have started.

Bus

A communication system that transfers data between components inside a computer, or between computers.

Status Bits

Flags used by devices to communicate the state of an IO operation to the operating system.

IO Port Space

The collection of IO ports where each register is assigned its own port number.