FW: Question regarding CMOS regions.

[<MohammadYounasKhan.P@Dell.com>]

Hi All,

As we know CMOS data can be 128 or 256 bytes. CMOS lower 128 bytes are stored in IO ports 0x70-0x71 whereas CMOS upper 128 bytes are stored using IO ports 0x72-0x73.

  1.  How to know that the system has 128bytes of CMOS or 256 bytes of CMOS region?
  2.  Is there any CMOS location which represents CMOS upper region is exists or valid or any other mechanism for it?
  3.  Are we replicating lower 128 bytes to upper 128 bytes in CMOS location 0x70-0x71 (or 0x72-0x73)? If yes, Why are we doing that?

Thank you,
Younas.