F71872
Keyboard reset and GateA20
Keyboard reset (kbrst_n) is pin p20 of microcontroller or hardware decode. It is selected by bit 0 of clock
select register(index F0h).GateA20 is pin p21 of microcontroller or hardware decode, It is selected by bit 1 of
clock select register(index F0h)
Kbrst_n
P20
Gatea20
KBC
P21
P26
P27
P23
P22
P24
P25
kbclk
kbdat
moclk
modat
kbirq
moirq
Host Phase
The table is keyboard controller interface with the system.
Read data: this is an 8 bit read only register, when system read this register; the interrupt and obf flag will be
cleared.
Write data: this is an 8 bit write only register, when system write this register, the ibf flag will be set.
Read status: this is an 8 bit read only register, it replay KBC status.
Write command: this is an 8 bit write only register, when system write this register, the ibf flag will be set.
Host address
R/W
R
Function
60h
60h
64h
64h
Read data
Write data
W
R
Read status
Write command
W
6.9 Dynamic Voltage Change Application
The F71872 supports an automatic/dynamic over-voltage function for application of over-clocking or
under clocking. This function provides a pin by external trigger signal to improve the CPU’s performance by
25
July, 2007
V0.28P
FINTEK [ FEATURE INTEGRATION TECHNOLOGY INC. ]
