LM81CIMT-31 National Semiconductor, LM81CIMT-31 Datasheet - Page 28

• Manufacturer Part Number: LM81CIMT-31
• Description: Serial Interface ACPI-Compatible Microprocessor System
• Manufacturer: National Semiconductor

www.national.com
0-3
4-5
6-7
2-6
1-7
0-1
2-6
Bit
Bit
Bit
Bit
0-1
7
0
7
Functional Description
13.10 VID/Fan Divisor Register — Address 47h
Power on default –
13.11 Serial Bus Address Register — Address 48h
Power on default – Serial Bus address
13.12 VID4 Register — Address 49h
Power on default –
13.13 Temperature Configuration Register — Address 4Bh
Power on default –
Serial Bus
Address
Serial Bus
Address
Reserved
VID4
Reserved
Temperature
Interrupt Mode
Select Bits
Reserved
Temperature
Resolution
VID
FAN1 RPM
Control
FAN2 RPM
Control
<
Name
Name
Name
Name
3:0
>
<
<
<
7:4
7:1
7:0
>
>
>
Read Only
Read/Write
Read/Write
Read/Write
is 0101, and
= 100 000,
= 0000 0001 binary
Read Only
Read/Write
Read/Write
Read Only
Read/Write
Read/Write
Read/Write
Read Only
Read/Write
Read/Write
Read/Write
<
(Continued)
<
<
0
6:0
>
3:0
The VID
operating voltage (e.g. 1.5V to 2.9V).
FAN1 Speed Control.
FAN2 Speed Control.
<
<
<
<
<
<
<
<
= VID4.
>
5:4
5:4
5:4
5:4
7:6
7:6
7:6
7:6
Serial Bus address
Serial Bus address
VID4 input from Pentium/PRO power supply that indicate the operating voltage of
the processor (e.g. 1.5V to 2.9V).
The state of these bits select the interrupt mode for INT as described below.
For 8-bit plus sign temperature resolution:
<
<
<
>
1:0
1:0
1:0
is mapped to VID
= 010 11(A1)(A0) and
>
>
>
>
>
>
>
>
>
>
>
= 00 - divide by 1;
= 01 - divide by 2;
= 10 - divide by 4;
= 11 - divide by 8.
= 00 - divide by 1;
= 01 - divide by 2;
= 10 - divide by 4;
= 11 - divide by 8.
<
= 00 or
= 01: One-Time Interrupt Mode
= 10: Comparator Mode
3:0
>
inputs from the Pentium/PRO power supplies that indicate the
<
28
1:0
<
<
<
>
1:0
6:2
3:0
= 11: Repetitive Interrupt Mode
>
>
<
>
7
= 010 11
= A1 A0
>
= 0 binary
Description
Description
Description
Description
<
7
>
= LSB ( 0.5˚C)