System BIOS

8.4.1 System ID and ROM Type

Diagnostic applications can use the INT 15, AX=E800h BIOS function to identify the type of system. This function will return the system ID in the BX register. Systems have the following IDs and ROM family types:

Table 8-3

System ID Numbers

System (Form Factor)

System ID

BIOS Family

 

 

 

USDT

1496h

J01

 

 

 

SFF

1495h

J01

 

 

 

MT

1497h

J01

 

 

 

CMT

1494h

J01

 

 

 

The ROM family and version numbers can be verified with the Setup utility or the System Insight Manager or Diagnostics applications.

8.4.2 Temperature Status

The BIOS includes a function (INT15, AX=E816h) to retrieve the status of a system's interior temperature. This function allows an application to check whether the temperature situation is at a Normal, Caution, or Critical condition.

8.5 SMBIOS Support

These systems support SMBIOS version 2.6. and usethe table-based method of accessing SMBIOS data. SMBIOS structures can be located by looking in the EFI Configuration Table for SMBIOS_TABLE_GUID and using the associated pointer. Refer to the SMBIOS 2.6 specification for more information on accessing SMBIOS data.

✎System information on these systems is handled exclusively through the SMBIOS.

8.6USB Legacy Support

The system BIOS ROM checks the USB port, during POST, for the presence of a USB keyboard. This allows a system with only a USB keyboard to be used during ROM-based setup and also on a system with an OS that does not include a USB driver.

On such a system a keystroke will generate an SMI and the SMI handler will retrieve the data from the device and convert it to PS/2 data. The data will be passed to the keyboard controller and processed as in the PS/2 interface. Changing the delay and/or typematic rate of a USB keyboard though BIOS function INT 16 is not supported.

Technical Reference Guide

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