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4.4 BIOS SOC Vortex86DX3 interface for reading serial number
To store the device parameters, the FRAM array is used. For storing the entire system
information, the size of 1Kbyte is used (might slightly differ depending on BIOS version).
4.4.1 Array structure
_FRAM
STRUCT
db
256 dup (0)
; Reserve for storing the CMOS
copy
dSerNum dd
0
; Product serial number
_FRAM
ENDS
Service interrupt combined with printer service interrupt.
To call the service, the
INT 17H
interrupt is used with a parameter in the AH = 0ADh register.
The values of other parameters passed in processor registers are shown below.
Where the function number (AL) is specified incorrectly, AX = -1 (0FFFFh) is returned.
4.4.2 Obtaining serial number of the device
Input:
AL = 6
Output:
AX = result code (0
– no error)
CX:DX = serial number.
4.5 SOC Vortex86DX3 BIOS interface for reading/writing to FRAM
Integrated FRAM is also available for storing user data.
To call the FRAM read/write service, the
INT 17H
interrupt is used with a parameter in the
AH = 0ADh register.
The values of other parameters transferred in processor registers are shown below. Where
the function number (AL) is specified incorrectly, the AX = -1 (0FFFFh) is returned.
4.5.1 Reading user data from FRAM
Input:
AL = 0Ch
BX = data start address in FRAM user area
CX = number of bytes read
DS:DX = indicates to the buffer for reading
