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CMOS Memory Map

Hkxs edited this page Sep 13, 2024 · 1 revision

Traditionally, BIOS settings were stored on a small non-volatile memory chip called CMOS, which was powered by a battery to retain the information in case of a power loss. This battery also powered the RTC (Real-Time Clock) of the motherboard.

This memory is outside of the "regular" memory region of the processor, but it is readable using IN/OUT instructions as shown in CMOS memory map (for Bochs PC emulator)

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