Owner manual

Functional Description (Continued)
12.8 Fan Divisor Register/RST_OUT/OS — Address 05h
Power on –
<
7:4
>
is 0101, and
<
3:0
>
is mapped to VID
<
3:0
>
Bit Name Read/Write Description
0 FAN1 Mode
Select
Read/Write A one selects the level sensitive input mode while a zero selects Fan count mode
for the FAN1 input pin.
1 FAN2 Mode
Select
Read/Write A one selects the level sensitive input mode while a zero selects Fan count mode
for the FAN2 input pin.
2-3 FAN1 RPM
Control
Read/Write FAN1 Speed Control.
<
3:2
>
= 00 - divide by 1;
<
3:2
>
= 01 - divide by 2;
<
3:2
>
= 10 - divide by 4;
<
3:2
>
= 11 - divide by 8.
If level sensitive input is selected:
>
2
<
= 1 selects and active-low input (An interrupt
will be generated if the FAN2 input is Low),
>
2
<
= 0 selects an active-high input (an
interrupt will be generated if the FAN2 input is High).
4-5 FAN2 RPM
Control
Read/Write FAN2 Speed Control.
<
5:4
>
= 00 - divide by 1;
<
5:4
>
= 01 - divide by 2;
<
5:4
>
= 10 - divide by 4;
<
5:4
>
= 11 - divide by 8.
If level sensitive input is selected:
<
2
>
= 1 selects and active-low input (An interrupt
will be generated if the FAN2 input is Low),
<
2
>
= 0 selects an active-high input (an
interrupt will be generated if the FAN2 input is High).
6 OS pin enable
Read/Write A one enables OS mode on the RST_OUT/OS output pin, while Bit 7 of this register
is set to zero. If bits 6 and 7 of this register are set to zero the RST_OUT/OS pin is
disabled.
7 RST enable
Read/Write A one sets the RST_OUT/OS pin in the RST mode. In the RST mode, bit 7 of the
Fan Divisor/RST_OUT/OS Register has to be set to one. If bits 6 and 7 of this
register are set to zero the RST_OUT/OS pin is disabled.
12.9 OS Configuration/Temperature Resolution Register—Address 06h
Power on default Serial Bus address
<
7:0
>
= 0000 0001 binary
Bit Name Read/Write Description
0 OS status
Read only Status of the OS.This bit mirrors the state of the RST_OUT/OS pin when in the OS
mode.
1 OS Polarity
Read/Write A zero selects OS to be active-low, while a one selects OS to be active high. OS is
an open-drain output.
2 OS mode select
Read/Write A one selects the one time interrupt mode for OS, while a zero selects comparator
mode for OS. (See in Section 7.0)
3 Temperature
Resolution
Control
Read/Write A zero selects the default 8-bit plus sign resolution temperature conversions while a
one selects 11-bit plus sign resolution temperature conversions. 8-bit plus sign
conversions time is approximately 100 ms, while 11-bit plus sign conversion time is
approximately 2 seconds.
4-7 Temp [3:0] Read/Write The lower nibble (4 LSBs) of the 11-bit plus sign temperature data.
<
4
>
= Temp
[0] (nibble LSB, 0.0625˚C),
<
5
>
= Temp [1],
<
6
>
= Temp [2],
<
7
>
= Temp 3
(nibble MSB, 0.5˚C). For 8-bit plus sign temperature resolution,
<
7
>
= Temp [0]
(LSB, 0.5˚C) while
<
4:6
>
are undefined.
LM80
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