Hardware, Firmware & the Operating System (Cambridge (CIE) O Level Computer Science) : Revision Note

Hardware, Firmware & the Operating System

How does application software, the operating system and hardware communicate?

• Application software talks to the operating system, this allows it to interact with the hardware 

• The hardware processes and sends the information to the operating system which talks directly to the applications software

• This process is repeated while application software is in use

What is firmware?

• Firmware is embedded directly in to the hardware of a device, to make them function

• When a computer is turned on, it has to explore the ROM for its initial boot-up instructions, these are contained in a Bootstrap loader 

• The initial process is handled by the basic input/output system (BIOS) which is known as firmware

• Once start-up is complete, instructions are sent to RAM to be processed by the operating system 

• This layer ensures that hardware devices e.g. keyboard and mouse are available and can be communicated directly by the operating system

• Firmware translates between the hardware and the software