W83977EG-AW Datasheet, PDF (84/142 Pages) Nuvotem Talema – These products are not designed for use in life support appliances

W83977EF-AW/W83977EG-AW
10.2.2 Configurate the configuration registers
The chip selects the logical device and activates the desired logical devices through Extended
Function Index Register(EFIR) and Extended Function Data Register(EFDR). EFIR is located at the
same address as EFER, and EFDR is located at address (EFIR+1).
First, write the Logical Device Number (i.e.,0x07) to the EFIR and then write the number of the desired
logical device to the EFDR. If accessing the Chip(Global) Control Registers, this step is not required.
Secondly, write the address of the desired configuration register within the logical device to the EFIR
and then write (or read) the desired configuration register through EFDR.
10.2.3 Exit the extended function mode
To exit the extended function mode, one write of 0xAA to EFER is required. Once the chip exits the
extended function mode, it is in the normal running mode and is ready to enter the configuration mode.
10.2.4 Software programming example
The following example is written in Intel 8086 assembly language. It assumes that the EFER is located
at 3F0h, so EFIR is located at 3F0h and EFDR is located at 3F1h. If HEFRAS (CR26 bit 6) is set,
3F0h can be directly replaced by 370h and 3F1h replaced by 371h.
;-----------------------------------------------------------------------------------
; Enter the extended function mode ,interruptible double-write |
;-----------------------------------------------------------------------------------
MOV DX,3F0H
MOV AL,87H
OUT DX,AL
OUT DX,AL
;-----------------------------------------------------------------------------
; Configurate logical device 1, configuration register CRF0 |
;-----------------------------------------------------------------------------
MOV DX,3F0H
MOV AL,07H
OUT DX,AL
; point to Logical Device Number Reg.
MOV DX,3F1H
MOV AL,01H
OUT DX,AL
; select logical device 1
;
MOV DX,3F0H
MOV AL,F0H
OUT DX,AL
; select CRF0
MOV DX,3F1H
MOV AL,3CH
OUT DX,AL
; update CRF0 with value 3CH
;------------------------------------------
; Exit extended function mode |
;------------------------------------------
MOV DX,3F0H
MOV AL,AAH
OUT DX,AL
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