F81866A Datasheet, PDF (67/210 Pages) Feature Integration Technology Inc. – 6 UARTs Super IO With 128 Bytes FIFO and Power

F81866A
00: Output PWM mode (push pull) to control fans.
01: Use linear fan application circuit to control fan speed by fan’s power
terminal.
1-0
FAN1_TYPE
R/W 3VCC
10: Output PWM mode (open drain) to control Intel 4-wire fans.
00
11: Reserved.
Bit 0 is power on trap by FANCTL1
0: FANCTL1 is pull up by external resistor.
1: FANCTL1is pull down by internal 100K Ω resistor.
S: Register default values are decided by trapping.
Fan1 Base Temperature Register – Offset 94h (FAN_PROG_SEL = 1)
Bit
Name
R/W Reset Default
Description
This register is used to set the base temperature for FAN1 temperature
adjustment.
The FAN1 temperature is calculated according to the equation:
Tfan1 = Tnow + (Ta – Tb)*Ct
FAN1_BASE
7-0
R/W 5VSB 0 Where Tnow is selected by FAN1_TEMP_SEL_DIG and
_TEMP
FAN1_TEMP_SEL.
Tb is this register, Ta is selected by TFAN1_ADJ_SEL and Ct is selected
by TFAN1_ADJ_UP_RATE/TFAN1_ADJ_DN_RATE.
To access this register, FAN_PROG_SEL (CR9F [7]) must set to “1”.
FAN1 Temperature Adjustment Rate Register ⎯ Index 95h (FAN_PROG_SEL = 1)
Bit
Name
R/W Reset Default
Description
7
Reserved
-
-
- Reserved
TFAN1_ADJ_UP
6-4
_RATE
5VSB
This selects the weighting of the difference between Ta and Tb if Ta is
higher than Tb.
3’h1: 1 (Ct = 1)
3’h2: 1/2 (Ct= 1/2)
3’h0
3’h3: 1/4 (Ct = 1/4)
3’h4: 1/8 (Ct = 1/8)
otherwise: 0
To access this byte, FAN_PROG_SEL must set to “1”.
3
Reserved
-
- Reserved
67
Jan, 2012
V0. 12P