Texas Instruments 5000 - Manual (Page 270)

Returns:
AH = 00h
AL = Current CPU Speed
00h = Low
01h = High
02h = Medium
BL = Current Auto Setting
00h = Off.
01h = On
F.6 Function F8h - Set CPU Speed
This function sets the CPU speed to low, medium, or high. Also, see related
function F7h.
For notebook computers configured with a i486DX2 CPU, this function will
not perform a speed switch if the notebook is currently running with pro-
tected mode active or emm386.exe active. The function will return an error
condition (86h and CY set).
Call with:
AH = F8h
AL = New CPU Speed
00h = Low
01h = High
02h = Medium
Returns:
AH = Error Code
00h = No Error
86h = Invalid Parameter
CY = Set on error (see AH)
F.7 Function F9h - Subfunction 5Eh
Get Model Information
This function returns a variety of information about the system, including
the OEM company, the system, LCD, and CPU types, and reports on the
presence of an internal floppy. It also returns the version numbers of the
chipset ICs if possible. Also, see related functions F963h, and FA00h.
Added Interrupt 15 Functions F-5