TWI534611B - Computer system, indicating method and indicating apparatus for hard disk status thereof - Google Patents

Description

Hard disk status display method, computer system and hard disk status thereof Display device

The present invention relates to an electronic digital data processing method and apparatus, and more particularly to a display method of a hard disk operating state, a computer system for indicating a hard disk operating state, and a hard disk state indicating device thereof.

A server computer using a disk array system often needs to simultaneously monitor the operation of a plurality of hard disks that are different from each other, and let the user intuitively know that each hard disk is currently operating in, for example, Not present, idle ( Idle), Access, Fault, or Offline to take immediate action on a hard drive error.

Referring to FIG. 1, the existing way of indicating the state of the hard disk is to use a serial attached SCSI controller (SAS controller) and an electrical connection to the serial attached small computer interface. And a plurality of hard disks 13 and having a plurality of serial attached Servo SCSI Expanders (SAS Expander) 12 and a plurality of buffers 14 electrically connected to the transport ports. And a plurality of light emitting units 15 electrically connected to the buffers 14 An operating system (not shown) that cooperates with the serial attached small computer interface expander 12 communicates with each hard disk 13 to exchange data and obtains three status packets from each hard disk 13 to separately analyze the existence thereof. The state, the normal state, the abnormal state, and the serial attached small computer interface expander 12 respectively output a presence state signal, a normal state signal and an abnormal state signal via the three transmission ports, respectively, by the corresponding buffer The device 14 receives the presence state signal and the normal state signal for processing and output, and then outputs the same to the corresponding light-emitting unit 15 together with the abnormal state signal to drive the light-emitting unit 15 to emit light or blink, so that the user can intuitively recognize The current operating status of each hard disk. However, the existing hard disk status indication method has the following disadvantages.

First, the number of transmission ports is required. Since the single hard disk 13 needs to use the three transmission ports of the serial attached small computer interface expander 12 to cooperate with the corresponding buffer 14, therefore, when simultaneously indicating When the plurality of hard disks 13 are in an operating state, the serial attached small computer interface expander 12 must have three times the number of hard disks to output the presence, normal, and abnormal state signals, for example, when When twenty-four hard disks 13 are to be monitored simultaneously, the serial attached small computer interface expander 12 must have seventy-two transmission ports to output the aforementioned signals to the buffer 14 for processing.

The physical circuit occupied by the serial attached small-sized computer interface expander 12, the buffers 14 and the light-emitting units 15 are electrically connected to each other, and are connected to the buffers 14 and the light-emitting units 15. The complexity of the circuit layout is high, and wiring errors may occur during the test phase, resulting in damage to the hardware circuit, thereby adding additional cost, so it is necessary to find a solution to the existing operation state of the hard disk.

Accordingly, a first object of the present invention is to provide a hard disk state display method that solves the aforementioned disadvantages.

Therefore, the hard disk state display method of the present invention is performed by a hard disk state indicating device electrically connecting a plurality of hard disks and a plurality of display units respectively corresponding to the hard disks, each hard disk being used for Sending a first packet indicating whether the indication is valid, and a second packet indicating that the state is abnormal, and each display unit generates a corresponding display state according to a driving signal indicating which state the hard disk corresponds to. And the hard disk state display method includes a step (A), a step (B), and a step (C).

Step (A): The hard disk status indication device receives the first packet, and determines whether the corresponding hard disk is valid according to the potential of the first packet, and if yes, performs step (B).

Step (B): The hard disk status indication device receives the corresponding second packet, and generates a pulse signal converted between a first logic level and a second logic level according to the second packet.

Step (C): The hard disk state indicating device is at the first logic level or the second logic level according to the pulse signal to generate a driving signal indicating whether there is an abnormality to the display unit corresponding to the hard disk.

A second object of the present invention is to provide a computer system capable of indicating the state of a hard disk, and a hard disk state indicating device for the computer system.

Thus, the computer system of the present invention comprises a plurality of hard disks and a plurality of displays The display unit and the hard disk status indicating device.

Each hard disk is used to send a first packet indicating whether it is valid or not, and a second packet indicating that its state is abnormal.

Each display unit corresponds to each hard disk, and generates a corresponding display state according to a driving signal indicating which state the hard disk corresponds to.

The hard disk status indication device includes a logic unit and an expansion unit having a plurality of transmission ports.

The logic unit is electrically connected to each transmission port of the expansion unit, and electrically connects each hard disk to receive each first packet, and determines whether the corresponding hard disk is valid according to the potential of the first packet.

The expansion unit is electrically connected to each hard disk, and when the logic unit determines that the hard disk is valid, receives the second packet corresponding to the hard disk, and generates a transformation according to the second packet to a first logic level and a a pulse signal between the second logic levels, and each of the transmission units outputs the pulse signal corresponding to each hard disk to the logic unit, so that the logic unit is in the first according to the pulse signal The logic level or the second logic level is used to generate a driving signal indicating whether there is an abnormality to the display unit corresponding to the hard disk.

The effect of the present invention is to determine, by the logic unit, the logic level at which each pulse signal output by the expansion unit is located, to determine which state each hard disk is in, and to drive each display unit accordingly. Corresponding display state, and thus only need to use the single transmission port of the expansion unit to bring the corresponding hard disk to the effect of indicating the state of the hard disk, and borrow the logic Unit to reduce the complexity of wiring.

11‧‧‧In-line attached small computer interface controller

24‧‧‧Steps for judging the pulse signal

25‧‧‧Steps for judging the normal state of the hard disk

12‧‧‧Sequential Attached Small Computer Interface Expander

251‧‧‧Substeps to initialize the first timer to start timing

13‧‧‧ Hard disk

14‧‧‧ buffer

252‧‧‧Substeps to judge the first logical timing

15‧‧‧Lighting unit

3‧‧‧ Hard disk

253‧‧‧Substeps to receive the third packet and initialize the second timer

4‧‧‧ display unit

5‧‧‧hard disk status indicator

254‧‧‧Subjects to determine if the third packet has a second predetermined time pulse

51‧‧‧Extension unit

52‧‧‧Logical unit

20‧‧‧Steps to determine if a hard disk is valid

255‧‧‧Substeps to keep the display unit continuously emitting green light

21‧‧‧Substeps to receive the first packet

256‧‧‧Substeps for the display unit to emit a flashing red light

22‧‧‧Substeps to detect the first packet

26‧‧‧Steps for judging the abnormal state of the hard disk

221‧‧‧Steps to make the display unit not illuminate

261‧‧‧Substeps for the display unit to continue to emit red light

23‧‧‧Steps to receive the second packet and generate a pulse signal

262‧‧‧Substeps for the display unit to flash red

Other features and effects of the present invention will be apparent from the following description of the drawings, wherein: FIG. 1 is a schematic diagram illustrating a conventional hard disk state indicating device; FIG. 2 is a schematic view showing the present invention. An embodiment of the disc state indicating device; FIG. 3 is a flow chart illustrating a hard disk state display method performed by the hard disk state indicating device; and FIG. 4 is a state transition diagram, and FIG. 3 illustrates the hard disk state display method.

Referring to FIG. 2, an embodiment of the computer system of the present invention includes a plurality of hard disks 3 (only two of which are shown), a plurality of display units 4 (only two of which are shown), and a hard disk indicating device 5. .

Each hard disk 3 is configured to send a first packet indicating whether the indication is valid, a second packet indicating whether the state is abnormal, and a third packet indicating that the state is normal, and the first packet is first explained, and the so-called effective Existence means whether the corresponding hard disk 3 is electrically plugged into a backplane, and the abnormal state includes that the corresponding hard disk 3 is in one of a fault or an offline, and the normal state is The corresponding hard disk 3 is included in one of an idle or an access.

Each display unit 4 is a hard disk 3 corresponding to an indication The driving signal of which state is operated to generate the corresponding display state. In this example, each display unit 4 indicates a red light emitting diode in which the corresponding hard disk 3 is abnormal by emitting red light ( Light Emitting Diode (LED), and a green light emitting diode that emits green light to indicate that the corresponding hard disk 3 is in a normal state.

The hard disk state indicating device 5 includes a first timer (not shown) for timing a first predetermined time and a second timer for timing a second predetermined time (not shown) a logic unit 52, and an expansion unit 51 having a plurality of transmission ports.

The logic unit 52 is electrically connected to each transmission port of the expansion unit 51, and electrically connects each hard disk 3 with its own first timer and the second timer to determine the state of the hard disk. In this example, the logic unit 52 is implemented by a Complex Programmable Logic Device (CPLD), and the logic circuit corresponding to the foregoing judgment operation hard disk state is downloaded and burned therein to perform logical judgment. Of course, the selection of the logic unit 52 is not limited thereto. For example, it may be implemented by selecting a Field Programmable Gate Array (FPGA), and the design logic may be input to implement a programmable logic synthesis and Wafer burning.

The expansion unit 51 is electrically connected to each hard disk 3, and each transmission port outputs the pulse signal corresponding to each hard disk 3 to the logic unit 52, so that the logic unit 52 is based on the logic of the pulse signal. The level is used to generate a driving signal indicating whether there is an abnormality to the display unit 4 corresponding to the hard disk 3. In this example, the expansion unit 51 includes electrical connections to each other. A series of attached Serial SCSI Controller (SAS controller), and a Serial Attached SCSI Expander (SAS Expander) with such a transport port. The serial attached small computer interface expander expands the transmission lane of the serial attached small computer interface controller and can electrically connect more hard disks 3 at the same time, and the serial attached small computer interface The transmission of the expander conforms to the Serial General Purpose Input/Output (SGPIO) interface specification to output the pulse signal. Certainly, the implementation manner of outputting the pulse signal is not limited thereto. For example, the pulse signal can also be directly output to the logic unit 52 by using a serial attached small computer interface controller with more output/output ports. It is not necessary to match the serial attached small computer interface expander. However, this can be easily changed by those who are familiar with the circuit technology, and will not be described here.

Before specifically describing this example, firstly, according to the corresponding hard disk 3 being in the presence of invalidity, error, disconnection, idle, and access, the display unit 4 indicates the state of the corresponding hard disk 3. Shown in the table below.

Referring to FIG. 3, the hard disk state indicating device 5 of the present invention executes a hard disk state display method to perform state determination for each hard disk 3 at the same time, and the implementation of the hard disk state display method includes the following steps.

First, step 20 is that the logic unit 52 receives the first seal. And determining whether the corresponding hard disk 3 is valid according to the potential of the first packet. This step 20 includes the following sub-steps.

In sub-step 21, the logic unit 52 receives the first packet.

In sub-step 22, the logic unit 52 determines whether the first packet is low. If it is low, it determines that the hard disk 3 is valid, and then proceeds to step 23; if it is high, it performs sub-step 221.

In sub-step 221, the logic unit 52 outputs a drive signal for the hard disk 3 corresponding to the indication to operate in the inactive presence state, and causes the corresponding display unit 4 to not emit light, and repeats the sub-step 21.

Next, in step 23, the extension unit 51 receives the second packet corresponding to the hard disk 3, and identifies whether the second packet is abnormal, and generates a transition between a first logic level and a second logic level. The pulse signal is output to the logic unit 52. It should be added here that since the expansion unit 51 only needs to receive the second packet to make an abnormal state determination on the corresponding hard disk 3, it is more convenient to receive the physical electrical connection line from the hard disk 3.

Next, in step 24, the logic unit 52 generates a driving signal indicating whether there is an abnormality to the display unit 4 corresponding to the hard disk 3 according to whether the pulse signal is at the first logic level or the second logic level. If the pulse signal is at the second logic level, the logic unit 52 determines that the hard disk 3 is operating in an abnormal state and then performs step 26; if the pulse signal is at the first logic level, the logic unit 52 determines the hard The disc 3 operates in a normal state and then proceeds to step 25.

In step 26, the pulse signal is at the second logic level, and the logic unit 52 further determines whether the hard disk 3 is offline or incorrect by whether the pulse signal is changed from the second logic level to the first logic level. If the result of the determination is yes, step 262 is performed, and if the result of the determination is otherwise, step 261 is performed.

Step 262: The logic unit 52 determines that the pulse signal jumps back and forth between the second logic level and the first logic level, and outputs a driving signal indicating that the corresponding hard disk 3 is operating in an offline state, so that the corresponding signal is The red light emitting diode emits a flashing red light.

Step 261: The logic unit 52 determines that the pulse signal is maintained at the second logic level, and outputs a driving signal indicating that the corresponding hard disk 3 is operating in an error state, so that the corresponding red light emitting diode continues to emit red. Light.

In step 25, the pulse signal is at a first logic level, and the logic unit 52 further performs the following sub-steps to determine whether the hard disk 3 is idle or accessed.

Sub-step 251: The logic unit 52 starts counting the first predetermined time using the first timer.

Sub-step 252: The logic unit 52 determines whether the pulse signal is at the first logic level for the first predetermined time. If the determination result is yes, proceed to sub-step 253; if the determination result is no, repeat the step 26.

Sub-step 253: The logic unit 52 receives the third packet and initializes the second timer to start timing the second predetermined time.

Sub-step 254: The logic unit 52 determines whether the third packet has a pulse for the second predetermined time, and in this example, the pulse is a pulse at the first logic level. If so, proceed to sub-step 255; if not, skip to sub-step 256.

Sub-step 255: the logic unit 52 determines that the third packet is a pulse at the first logic level for the second predetermined time, and outputs a driving signal indicating that the corresponding hard disk 3 is operating in an idle state. The corresponding green light emitting diode continuously emits green light.

Sub-step 256: the logic unit 52 determines that the third packet is a pulse that jumps between the first logic level and the second logic level, and outputs a driving signal indicating that the corresponding hard disk 3 is operating in an access state. The corresponding green light emitting diode emits a flashing green light.

Referring to FIG. 4, the state of the hard disk state display method is further illustrated by using a state transition diagram as an example. In this example, the first logic level is logic 0, and the second logic level is logic 1. However, this can still be implemented in reverse depending on the factory specifications of each hard disk, and is not limited to this example. Further, the first predetermined time is set to 1.5 seconds, and the second predetermined time is 0.5 seconds.

First, as long as the first packet indicating whether the hard disk 3 is effectively present is at a high potential, the corresponding hard disk 3 is directly indicated to be invalid in any state, and the corresponding red light emitting diode and the green color are made. The light emitting diode does not emit light.

Then, when the first packet is at a low potential, it is further determined whether the pulse signal is at logic 0 for 1.5 seconds, and if so, it is determined that the corresponding hard disk 3 is in a normal state, and is turned to the upper half of the figure. at this time Only the green LED emits light, and the hard disk 3 is determined to be idle or accessed by determining the third packet. If the third packet has a pulse of logic 0 for 0.5 seconds, the hard disk 3 is indicated. Being in an idle state, and causing the corresponding green light emitting diode to continuously emit green light; if the third packet has a pulse that is changed between logic 1 and logic 0, indicating that the hard disk 3 is in an access state, and The corresponding green LED emits a flashing green light.

However, when the first packet is at a low potential and the pulse signal is at logic 1, it is determined that the corresponding hard disk 3 is in an abnormal state, and is turned to the lower half of the figure, and only the red LED is illuminated at this time. And determining the hard disk 3 to be disconnected or error by judging the pulse signal, if the pulse signal is at logic 1, indicating that the hard disk 3 is in an error state, and causing the corresponding red light emitting diode to emit red Light; if the pulse signal changes back and forth between logic 1 and logic 0, it indicates that the hard disk 3 is in a disconnected state, and the corresponding red light emitting diode emits a blinking red light.

It should be emphasized here that in this embodiment, even if the logic unit 52 determines that the hard disk 3 is operating in a normal state and starts to use the third packet for parsing, since the logic unit 52 still preferentially determines the pulse. Whether the signal is in logic 0 for 1.5 seconds to decide whether to receive the third packet, to avoid jumping back to logic 1 after parsing the pulse signal, therefore, the pulse signal is repeated again within 1.5 seconds or after 1.5 seconds. Now logic 1, the logic unit 52 will then determine that the corresponding hard disk 3 is in an abnormal state, and decide to cause the display unit 4 to continuously emit red light or blink red light. Therefore, the abnormal state has a higher priority in the process of parsing, and can be preferentially solved when the hard disk 3 has an error or a disconnected state. The user is informed of whether the current hard disk 3 corresponding to the abnormality has occurred.

In summary, the hard disk state indicating device 5 of the present invention outputs a pulse signal of the corresponding hard disk 3 by one of the expansion units 51 by the logic unit 52, and is first by the logic unit 52. And the second timer divides the time, and can simultaneously parse out the five states of the invalid presence, error, disconnection, idle, and access of the corresponding hard disk 3, thereby having the following advantages.

1. The same number of hard disks requires less transmission. Since the present invention only needs to transmit the pulse signal by using one of the transmission units of the expansion unit 51, when it is desired to monitor twenty-four hard disks at the same time. Only twenty-four transmission ports of the expansion unit 51 need to be occupied to transmit the pulse signal to the logic unit 52 for subsequent state analysis, so that forty-eight transmission ports can be saved compared to the conventional one, thereby making the remaining unused. The transmission port can then accommodate other simple logic circuits to be combined to greatly improve the efficiency of use of the transmission ports.

Second, the logic unit 52 performs subsequent state analysis on the hard disk 3, thereby omitting the circuit layout with an additional logic judging circuit such as a buffer, thereby preventing the wiring error from occurring when the plurality of hard disks 3 are simultaneously monitored. In addition, since the logic unit 52 can repeatedly perform the burning, when the logic relationship between the logic circuit and the hard disk corresponding to the display unit 4 is to be changed at any time during the testing phase, the modification can be performed at any time without being like a habit. It is known that only the hardware circuit can be replaced, thereby saving the cost of the physical circuit, and the object of the present invention can be achieved.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the patent application scope and patent specification content of the present invention, All remain within the scope of the invention patent.

3‧‧‧ Hard disk

4‧‧‧ display unit

5‧‧‧hard disk status indicator

51‧‧‧Extension unit

52‧‧‧Logical unit

Claims (10)

A hard disk state display method is performed by a hard disk state indicating device electrically connecting a plurality of hard disks and a plurality of display units respectively corresponding to the hard disks, and each hard disk is used for transmitting an indication Whether the first packet is valid or not, and a second packet indicating whether the state is abnormal or not, and each display unit generates a corresponding display state according to a driving signal indicating which state the hard disk is operated in, and The hard disk status indicating device includes a logic unit and an expansion unit electrically connected to each hard disk. The expansion unit is electrically connected to each hard disk and has a plurality of transmission ports respectively electrically connected to the logic unit. The hard disk status display method includes: (A) the logic unit of the hard disk status indication device receives the first packet, and determines whether the corresponding hard disk is valid according to the potential of the first packet, and if yes, performs the step (B) (B) the expansion unit of the hard disk status indication device receives the corresponding second packet, and identifies whether the second packet is abnormal, and generates a transformation to a first logic level. a pulse signal between the second logic level is output to the logic unit via the corresponding transmission port; and (C) the logic unit of the hard disk state indicating device is at the first logic level according to the pulse signal or The second logic level is used to generate a driving signal indicating whether there is an abnormality to the display unit corresponding to the hard disk. The hard disk state display method of claim 1, wherein the effective existence is that the corresponding hard disk is electrically connected to a backplane, wherein the step (A) further comprises: (A1) when the logic unit of the hard disk status indication device detects that the first packet is at the first potential, performing step (B), (A2) if the first packet is at the second potential, the hard disk status indication The logic unit of the device outputs a driving signal indicating that the corresponding hard disk is operating in an invalid presence state, so that the corresponding display unit does not emit light. The hard disk state display method of claim 1, wherein the abnormal state includes one of an error or a disconnection of the corresponding hard disk, and the hard disk state display method further comprises: (D1) the hard disk The logic unit of the status indicating device determines whether the pulse signal is changed to the first logic level by the second logic level when the pulse signal is at the second logic level, (D2) if the step (D1) If the result of the determination is yes, the logic unit outputs a driving signal indicating that the corresponding hard disk is operating in an error state, so that the corresponding display unit continues to emit light, (D3) if the result of the step (D1) is negative, then The logic unit outputs a driving signal indicating that the corresponding hard disk is operating in a disconnected state, so that the corresponding display unit blinks. The hard disk state display method of claim 3, each hard disk further sends a third packet indicating that the state is normal, and the hard disk state display method further comprises: (E1) logic of the hard disk state indicating device The unit determines whether the time at which the pulse signal is at the first logic level is longer than a first predetermined time to decide whether to receive the third packet or to repeat step (D1). The hard disk status display method of claim 4, wherein the normal state comprises the corresponding hard disk being in an idle or an access, and the hard disk status display method further comprises: (E2) if the step (E1) determining that the pulse signal is at the first logic level for the first predetermined time, the logic unit of the hard disk status indication device receives the third packet, and determines whether the third packet has a long time a pulse of a second predetermined time, (E3) if the result of the step (E2) is YES, the logic unit outputs a driving signal indicating that the corresponding hard disk is operating in an idle state, so that the corresponding display unit continues Illumination, (E4) If the result of the step (E2) is no, the logic unit outputs a drive signal indicating that the corresponding hard disk is operating in the access state, so that the corresponding display unit blinks. A computer system comprising: a plurality of hard disks, each hard disk is configured to send a first packet indicating whether the indication is valid, and a second packet indicating whether the state is abnormal; the plurality of display units are respectively correspondingly hard Each display unit generates a corresponding display state according to a driving signal indicating which state the hard disk operates in accordance with a state; and a hard disk state indicating device, including a logic unit, and a plurality of transmissions An expansion unit electrically connecting each transmission port of the expansion unit, and electrically connecting each hard disk to receive each first packet, and determining whether the corresponding hard disk is corresponding according to the potential of the first packet Effectively exist, The expansion unit is electrically connected to each hard disk, and when the logic unit determines that the hard disk is valid, receives the second packet corresponding to the hard disk, and identifies whether the second packet is abnormal, and generates a transformation into a first logic. a pulse signal between the level and a second logic level, and each of the transmission units outputs the pulse signal corresponding to each hard disk to the logic unit, so that the logic unit is based on the pulse signal The first logic level or the second logic level is used to generate a driving signal indicating whether there is an abnormality to the display unit corresponding to the hard disk. The computer system of claim 6, wherein the effective presence is that the corresponding hard disk is electrically plugged into a backplane, and when the logic unit detects that the first packet is at the first potential, The corresponding hard disk is valid, and the expansion unit generates a pulse signal corresponding to the second packet of the hard disk. When the logic unit detects that the first packet is the second potential, it determines that the corresponding hard disk is invalid. And the logic unit outputs a driving signal indicating that the corresponding hard disk operates in an invalid presence state, so that the corresponding display unit does not emit light. The computer system of claim 6, wherein the abnormal state comprises the corresponding hard disk being in one of an error or a disconnection, and the logic unit is when the pulse signal is at the second logic level. Determining whether the pulse signal is changed to the first logic level by the second logic level, and if the logic unit determines that the result is yes, outputting an indication corresponding to The hard disk operates on the driving signal in the error state, so that the corresponding display unit continues to emit light. If the logic unit determines that the result is no, a driving signal indicating that the corresponding hard disk is operating in the disconnected state is output. The corresponding display unit flashes. The computer system of claim 8, wherein the normal state comprises the corresponding hard disk being in an idle or an access, and each hard disk is further configured to send a third packet indicating that the state is normal. And the logic unit has a first timer for timing a first predetermined time, and a second timer for timing a second predetermined time, the logic unit determining, by the first timer Whether the time when the pulse signal is at the first logic level is longer than a first predetermined time to decide whether to receive the third packet, or to output the hard disk operation corresponding to the indication according to the logic level of the pulse signal a driving signal in an erroneous or disconnected state, if the logic unit determines that the pulse signal is at the first logic level for the first predetermined time, the logic unit receives the third packet, and the second a timer, determining whether the third packet has a pulse for the second predetermined time, and if the logic unit determines that the result is YES, outputting a driving signal indicating that the corresponding hard disk is operating in an idle state, And causing the corresponding display unit to continuously emit light, and if the logic unit determines that the result is no, outputting a driving signal indicating that the corresponding hard disk is operating in the access state, so that the corresponding display is performed. The unit flashes. A hard disk status indicating device electrically connecting a plurality of hard disks and a plurality of display units respectively corresponding to the hard disks, each hard disk for transmitting a first packet indicating whether the presence is valid, and an indication of whether the state is abnormal The second packet, each display unit generates a corresponding display state according to a driving signal indicating which state the hard disk is operated in, and the hard disk state indicating device comprises: a logic unit, each of which is electrically connected a hard disk to receive each first packet, and determining whether the corresponding hard disk is valid according to the potential of the first packet; and an expansion unit electrically connected to each hard disk to determine the hard in the logic unit Receiving a second packet corresponding to the hard disk when the disc is valid, and identifying whether the second packet is abnormal, and generating a pulse signal that is transformed between a first logic level and a second logic level, and the expansion unit Having a plurality of transmission ports respectively electrically connected to the logic unit, each transmission port respectively outputting the pulse signal corresponding to each hard disk to the logic unit, thereby causing the logic unit to The pulsed signal is in the first logic level or the second logic level to generate a drive signal to the display unit indicating the presence or absence of a hard drive to be abnormal.