Datasheet

6-Channel Intelligent Fan Controller
MAX31785
27
PMBus Commands
A summary of the PMBus commands supported by the device are described in the following sections.
PAGE (00h)
The device can control up to six fans, up to 11 temperature sensors, and measure up to six remote voltages using one
PMBus (I
2
C) address. Send the PAGE command with data 0 to 22 to select which fan, temperature sensor, or remote
voltage fan is affected by all the PMBus commands shown in Table 1. Not all commands are supported within each
page. If an unsupported command is received, the CML status bit is set. Some commands are common, meaning that
any selected page has the same effect on and the same response from the device.
Set the PAGE to 255 when it is desired that the following PMBus commands should apply to all pages at the same time.
Table 9. Page Commands
PAGE (DEC) ASSOCIATED CONTROL
0 Fan Connected to PWM 0
1 Fan Connected to PWM 1
2 Fan Connected to PWM 2
3 Fan Connected to PWM 3
4 Fan Connected to PWM 4
5 Fan Connected to PWM 5
6 Remote Thermal Diode Connected to ADC 0
7 Remote Thermal Diode Connected to ADC 1
8 Remote Thermal Diode Connected to ADC 2
9 Remote Thermal Diode Connected to ADC 3
10 Remote Thermal Diode Connected to ADC 4
11 Remote Thermal Diode Connected to ADC 5
12 Internal Temperature Sensor
13 Remote I
2
C Temperature Sensor with Address 0
14 Remote I
2
C Temperature Sensor with Address 1
15 Remote I
2
C Temperature Sensor with Address 2
16 Remote I
2
C Temperature Sensor with Address 3
17 Remote Voltage Connected to ADC 0
18 Remote Voltage Connected to ADC 1
19 Remote Voltage Connected to ADC 2
20 Remote Voltage Connected to ADC 3
21 Remote Voltage Connected to ADC 4
22 Remote Voltage Connected to ADC 5
23 to 254 Reserved
255 Applies to All Pages