CN104317682A - Design method for realizing rapid distinguishing and identifying of abnormal state of fan stalling - Google Patents

Abstract

The invention provides a design method for quickly distinguishing and identifying the abnormal state of fan stop, which belongs to the field of servers. A pin connected to the ground pin is added to the current fan end, and the corresponding pin is connected to the fan terminal end on the motherboard end. The pin is pulled up and connected to the BMC, named PRESENT signal. By monitoring the high and low levels of this signal, the judgment of the abnormal stall status of the fan can be realized, and it can help engineers quickly determine the status of the fan.

Description

A Design Method for Realizing Rapid Differentiation and Recognition of Abnormal State of Fan Stall

technical field

The invention relates to the field of servers, and in particular utilizes a design method for quickly distinguishing and identifying abnormal states of fan stalls. Realize the judgment of the abnormal stall status of the fan, and provide help for engineers to quickly determine the status of the fan. the

Background technique

With the large number of applications of servers in the Internet market and the application of large-scale data computer rooms becoming more and more common, the number of server applications will also increase exponentially, and each computer room consumes more and more power consumption, and power consumption and temperature, Heat dissipation has a lot to do with it, and the temperature and heat dissipation need to be controlled strictly according to the fan. Therefore, the normal operation of the fan is very important to the server. It not only affects the power consumption, but also involves many components in the server. lifespan and performance.

In a common server, there is generally an onboard BMC management chip to realize the management of the mainboard and the monitoring function of the working state, especially the control and monitoring of the fan speed. In the current server, there are generally two signals for the connection between the BMC and the fan: the PWM signal is used to control the fan speed; the TACH signal is used to monitor the fan speed. The fan speed can be controlled and monitored through the BMC. When the speed of the fan is abnormal, the BMC will monitor the system and give an alarm to notify the maintenance personnel that the fan has failed. Currently, a common server can implement fan fault monitoring and alarm functions, but cannot further distinguish the difference between a fan stall and whether the fan exists. That is, it is impossible to distinguish whether the fan has no speed due to abnormal stop or whether the fan is in place. the

Contents of the invention

Aiming at the above-mentioned problems currently encountered, this paper proposes a design method to quickly distinguish and identify abnormal states of fan stalls.

The method is simple in design and easy to implement. Add a pin connected to the ground pin on the current fan end, pull up the pin on the fan terminal end corresponding to the pin on the motherboard end and connect it to the BMC at the same time, named PRESENT signal, by monitoring the high and low voltage of the signal level, to realize the judgment of the abnormal stall status of the fan, and provide help for engineers to quickly determine the status of the fan.

The main idea of this design method is: add a pin connected to the ground pin on the fan side, pull up the pin on the motherboard side and connect it to the BMC at the same time, and monitor the output from the fan. The speed TACH signal and the present signal realize the distinction between the two states when the fan stops abnormally.

Compared with the current server, the system design is very simple, that is, a PRESENT signal is added between the fan terminal and the fan.

The hardware design circuit consists of four parts, which are the BMC management system, the fan terminal, the pull-up line of the PRESENT signal, and the fan.

Among them, the BMC management system is the identification part of the hardware design circuit. The management system detects the PRESENT signal and the TACH signal to quickly distinguish the abnormal state when there is no fan speed detected; the fan terminal mainly serves as a bridge.

One: the power required by the fan is provided to the fan through this terminal; the other: the status of the fan is transmitted to the BMC management system through the fan terminal; the PRESENT signal pulls up the line, mainly when the fan is not connected to the PRESENT The signal is fixed at a high level; the fan needs to add a present signal, and at the same time, connect the signal to a low level inside the fan. In this way, when a fan is connected to the fan terminal on the motherboard, PRESENT will be pulled down from high level to low level, thereby notifying the BMC management system that a fan has been connected to the fan terminal.

There is a BMC control circuit in the motherboard, which can realize the speed control of the fan;

The fan in the motherboard can feed back the current speed to the BMC circuit to monitor the fan speed;

The fan used in the motherboard needs to add a present signal pin to realize the monitoring of the existence of the fan;

The BMC management system in the main board realizes the state distinction and identification between the fan non-existence and abnormal stall through the newly added present signal and speed monitoring signal.

Description of drawings

Figure 1 is a block diagram of the hardware circuit for rapid identification of the abnormal state of the fan stop.

Detailed ways

The content of the present invention is described in more detail below:

Add a pin connected to the ground pin on the current fan side, pull up the pin corresponding to the fan terminal side of the pin on the motherboard side and connect it to the BMC at the same time, named PRESENT signal.

The hardware design circuit consists of four parts, which are the BMC management system, the fan terminal, the pull-up line of the PRESENT signal, and the fan.

Among them, the BMC management system is the identification part of the hardware design circuit. The management system detects the PRESENT signal and the TACH signal to quickly distinguish the abnormal state when there is no fan speed detected; the fan terminal mainly serves as a bridge.

As shown in Figure 1, this figure is a block diagram of the hardware circuit for quick distinction and identification of the abnormal state of the fan stop. The PRESENT signal part is a new place compared with the current general circuit. The main implementation methods of this design method are:

1) The BMC monitors the TACH signal and the Present signal in real time. When the fan is in a normal working state, the TACH signal has a corresponding speed and the Present signal is in a low state.

2) When the BMC detects that the TACH feedback speed is zero, it will judge the Present signal again:

A. When the present signal is detected to be low level, it indicates that the fan exists, but the fan is abnormal and the speed is zero, and the maintenance or replacement of the fan is required

B. When it is detected that the Present signal is at a high level, it indicates that the fan does not exist, and it is necessary to judge whether the fan is pulled out by human factors or the fan is forgotten to be plugged in.

3) Through the above working method, BMC realizes the monitoring of TACH signal and Present signal, so as to distinguish the status of abnormal fan stop, and provide help for quick solution to the problem.

Claims (3)

1. A design method for quickly distinguishing and identifying the abnormal state of fan stalling, characterized in that adding a pin connected to the ground pin at the fan end, and performing this pin on the motherboard end The pull-up is connected to the BMC at the same time, and the speed TACH signal and the present signal sent by the fan are monitored at the same time, so as to distinguish the two states when the fan stops abnormally. 2. The method according to claim 1, wherein the hardware design circuit is composed of four parts, which are respectively BMC management system, fan terminal, pull-up circuit of PRESENT signal, and fan, and the BMC management system is the hardware design circuit The identification part, the management system detects the PRESENT signal and the TACH signal, and quickly distinguishes the abnormal state when there is no fan speed detected; the fan terminal mainly serves as a bridge. 3. The method according to claim 2, characterized in that the function of the fan terminal is: firstly, to provide the power required by the fan to the fan through the terminal; secondly: to transmit the status of the fan through the fan terminal To the BMC management system; the pull-up line of the PRESENT signal is mainly to fix the PRESENT signal at high level when the fan is not connected; the fan needs to add the present signal, and at the same time, connect the signal to the low level inside the fan; In this way, when a fan is connected to the fan terminal on the motherboard, PRESENT will be pulled down from high level to low level, thereby notifying the BMC management system that a fan has been connected to the fan terminal.