Device Drivers

custom code that has information on how to handle/talk to hardware like harddrives,

mouse and printers.

Most of the Time Drivers Come with the Device

Keyboard Controller

figures out what key you pressed on your keyboard

Interrupt Request Line

 (IRQ)

16 traces that carry the signals to interrupt what the CPU is working on

7 of 16 lines are dedicated to specific hardware such as keyboard

Interrupt Controller

orders in urgency and rank the 256 possible types of interrupts for the CPU to handle

type of "chief-of Staff" to the CPU

INTR

-a pin at the bottom of the CPU that recives the signal from the interrupt controller

-handles theInterruptable Interrupts

-Low priority

NMI

-another pin used by the CPU to collect signals from the Interrupt Controller

-handles interrupts that Can't Be interrupted at all

Stack

If a cpu is working on a project and becomes interrupted the CPU places the Project in a memory address and bookmarks its place. When finished with the Interrupt goes back to the first item it stacked and continues

Interrupt Descriptor Table

(IDT)

a table that the CPU refrences to figure out what function to use in a specific program

ex) pressing letter 'A' in work gives A but

may also move forward in a Game

RET

(Return from Interrupt)

after the interrupt is finished this command is sent to the CPU to return it back to working freely or the stack

Enumerator program

when new hardware is installed this program identifies the hardware and its specific information

Hardware Tree

a database stored on the RAM that the OS access' to complete the resource arbitration

Resource Arbitration

the OS decides what resouces and types of interrupts get allocated to it