Octagon XE-900, Справочное руководство

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Return CPU Type
This function returns the CPU type and the system clock speed.
Function: 0fbh
Sub-Function: 01h
Purpose: To obtain the CPU type and clock speed
Calling Registers:
AH 0fbh
AL 01h
DX 0ffffh
Return Registers:
Carry flag cleared if successful
AH E0 = VIA C3
BX Clock speed in Mhz ie.733 etc.
CX Speed Index found during INT 17
initialization
DX reserved.
SI Current Speed Index
Carry flag set if error
AL Error code
Comments:
This function returns the CPU type.
Programming example:
unsigned char cpuMajor;
unsigned char cpuMinor;
/* Inline assembly code for Borland C++ 3.1 */
asm {
MOV AX, 0fb01h
MOV DX, 0ffffh
INT 17h
MOV cpuType, AH
}
if (cpuType == 0xE0
printf(“CPU type is VIA EDEN\n”);
CPU fan
The XE–900 733 MHz and 1 GHz versions come with a either a cooling fan on the
CPU or an Integrated Conductive Cooling System (see next section). The fan runs
continuously when power is applied to the card. A tachometer feedback sends
information back to the Southbridge.
Accessing CPU fan speed and temperature sensor registers is accomplished
through operating system drivers. Contact Octagon Systems for driver availability
and/or a Board Support Package for your Operating System (OS).