Ever wondered what goes on behind the scenes, when you press that win start button and get the pop up? Within that microsecond’s delay, here are some quick step-by-step explanation what goes behind the scenes.
1) Process Initiation
After the windows key is pressed, a scan code is generated, scan code is the binary code released to the pressed on the keyboard.
2) Interrupting the processor
Keyboard micro-controller interprets the scan code and stores it in the special memory till the processor is ready. A hardware interrupt is sent to the CPU for further action.
3) The Processor
Initially, the interrupt from the micro-controller is kept in a queue, till the processor is free. On coming across the scancode, it is routed to the operating system. The OS decides for what task the key was pressed.
4) Calling RAM
The OS involves the Explorer which determines that the win start key was pressed. Necessary 0s and 1s are generated to be sent to RAM.
5) OS Role
The explorer calls the OS to display the output on the monitor. OS reads RAM and sends the output to the video memory of the graphics card.
6) Mission Achieved
The graphics card shootout the relevant signals via the display port. This causes the Start Menu pop-up to display on your monitor, the next time it refreshes.
