Primary checks that are performed by post:

• The CPU registers have been checked.
• The integrity of the BIOS code is tested, as well as the basic components such as the DMA and timer.
• The memory of the system is inspected and confirmed.
• All of the system buses have been found, catalogued, and activated.
• After that, the BIOS is set up.
• Prepare the environment that the OS requires to run.
  
• The majority of the checks are done on: Processors, storage devices, and memory are examples of hardware elements. Keyboards and other peripheral devices are basic system devices. Processor Registers

• DMA stands for Direct Marketing Association (Direct Memory Access) Interrupt timer controller
  
  

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