Device
and operation
CPC307
C P C 3 0 7 U s e r M a n u a l
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© 2 0 2 2 F a s t w e l v . 0 0 6
- switch on the module
’s power.
- enter the module's BIOS SETUP and set the required BIOS settings.
4.3.16.3 Operation with FRAM
Note
The least-significant 1 KB of the FRAM memory is reserved! Writing to this area may
cause non-stable operation of the module.
The module has 32 KB of non-volatile FRAM memory. The user has access to the most-significant
31 KB. The memory is accessed through the SPI interface.
The user can address the FRAM memory directly through the registers of the SPI interface. More
detailed information can be found in the description on the Vortex86DX SoC (A9121) and FRAM
memory, which can be found in the relevant folder on the FTP server.
Working with the memory FRAM by BIOS is carried out through the function INT 17h (service
interrupt FRAM is combined with the interrupt printer service).
To call the FRAM service, an interrupt INT 17h with a parameter in the register AH = 0ADh is used.
The values of other parameters passed in the processor registers are given below.
Where the function number (AL) is specified incorrectly, this will make to return AX = -1 (0FFFFh).
FRAM memory structure:
_FRAM STRUCT
db 256 dup (0) ; Reserve for storing CMOS copy
dADCVS dd 4*8*2 dup (0) ; Reserved for CPC306
dADCCS dd 2*8*2 dup (0) ; Reserved for CPC306
dDACVS dd 3*2*2 dup (0) ; Reserved for CPC306
dSerNum dd 0 ; Serial number of the module
_____________________________
1)
The standard cable is not included in the delivery checklist and optional accessories of the module,
to be purchased as an option.
wMac dw -1,-1,-1 ; MAC address of the embedded Ethernet controller
wCheck dw 0 ; Array checksum
bUser db ? ; Start of the user area
_FRAM ENDS
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Obtaining serial number of the module.
Input: AL = 6
Output: AX = result code (0 - no error)
CX:DX = serial number.
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Reading MAC address of embedded Ethernet from FRAM field.
Input: AL = 8
Output: AX = result code (0 - no error)
