009 Embedded Linux-ARM. StorageQueries and discussion related to usage of Linux on ARM based devices. Linux has been ported to a variety of CPUs which are not only primarily used as the processor of a desktop or server computer, but also ARM, AVR32, ETRAX CRIS, FR-V, H8300, IP7000, m68k, MIPS, mn10300, SuperH, and Xtensa processors, It is also used as an alternative to using a proprietary operating system and toolchain. » 009.01.Linux Boot Process
The POST process starts when the electrical signal received is in " Power Good phase ". This is where a self-test to check the signals of all the connected hardware are good and all the hardware connected is in normal operating conditions. Hardware such as CPU, GPU, SSD any external memory devices, keyboards, display, etc are connected and there is no wrong signal received during the powerup phase. If any hardware gives a wrong signal the BIOS firmware will not be booted and the system will not boot.
POST, Power On Self Test, as the name suggests is a self test done when device is powered ON. Before BIOS directs to the address of Boot Loader, a basic test is done with all connected hardware. A test signal is sent and if it is acknowledged successfully then only BIOS refers to the address for Boot Sequence.
POST is used to check the basic functionality of the hardware by sending signal to each hardware comment and check for its response . Once its gets the response the system proceeds with boot process .
A power-on self-test (POST) is a set of routines performed by firmware or software immediately after a computer is powered on, to determine if the hardware is working as expected. The process would proceed further only if the required hardware is working correctly, else the BIOS(Basic Input Output Software) would issue an error message.
The error message could consist of text messages on the console or audio in the form of beeps.
