Error Code Detection Device and Error Code Detection Method

Abstract

The present invention provides an error code detection device and an error code detection method. The present invention can effectively utilize the advantages of the handshake method and flexibly and easily adjust the state transition conditions. A state transition setting screen (11) of a data stream of an overall state transition including names (12) of respective states based on a communication standard and state transition conditions (13) executed between the states is displayed on a display screen (6a), and in the state transition setting screen (11), input setting of the state transition conditions can be performed.

Description

Technical Field

[0001] The present invention relates to an error code detection device and an error code detection method for transmitting a known waveform as a test signal to a device under test in a state where the device under test is transitioned to a signal return state by a handshake based on a communication standard with the device under test, and detecting an error code of input data returned and received from the device under test accompanying the transmission of the test signal. Background Art

[0002] For example, the following method is generally adopted: Under a communication standard of a high-speed serial bus such as PCI Express and USB (Universal Serial Bus), when testing a receiver as a device under test, after performing a handshake that transitions the receiver to a test-specific signal return state (Loopback.Active), a known waveform for testing is input, and the bit error rate of the returned signal is confirmed.

[0003] When transitioning the device under test to the signal return state (Loopback.Active), two methods are known: (1) a fixed sequence type method in which the state of the device under test is transitioned by transmitting a fixed sequence, and (2) a handshake type method in which the signal of the device under test is analyzed to perform a handshake based on the actual high-speed serial bus standard and transition its state.

[0004] In addition, as the handshake type method of (2) related to the present invention, for example, as disclosed in Patent Document 1 below, a method is known in which a training waveform generated according to an instruction from a link state management unit is transmitted to the device under test to transition the link state of the LTSSM (Link Training&Status State Machine) of the device under test to the signal return state (Loopback.Active).

[0005] Here, the advantage of the fixed sequence type method of (1) is that the user can select all waveform combinations, and by adjusting the transmission time of each waveform within the fixed sequence, flexible debugging can be performed even on a device under test under development that cannot fully operate according to the communication standard. However, the disadvantage of the fixed sequence type method of (1) is that it is necessary to adjust the fine transmission time of the fixed sequence while capturing waveforms for each device under test, and this adjustment takes a considerable amount of time.

[0006] In contrast, the advantage of the handshaking method of (2) is that it can be stably used mainly for the DUT that can ensure actions in accordance with the communication standard, and the DUT under test can be transitioned to the signal return state (Loopback.Active) without making fine adjustments to the transmission time as in the fixed sequence method of (1).

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2017-098615

[0008] However, the handshaking method of (2) has the following problems: There are few setting items, and the DUT can only be made to act in accordance with the communication standard. When the handshaking fails, the state transition conditions cannot be adjusted on the user side. This mainly causes problems during the testing of the DUT during development. That is, as the final product of the DUT, it needs to act in accordance with the communication standard. As a result, during development and debugging, there is a requirement to flexibly transition the state of the DUT by having an adjustment range for the state transition conditions on the side of the error detection device, but there is a problem that this requirement cannot be achieved by the handshaking method of (2). Summary of the Invention

[0009] Therefore, the present invention has been completed in view of the above problems, and its object is to provide an error detection device and an error detection method that can effectively utilize the advantages of the handshaking method and flexibly and easily adjust the state transition conditions.

[0010] In order to achieve the above object, in the error detection device according to the first aspect of the present invention, in a state where the DUT W is transitioned to the signal return state through handshaking based on the communication standard, a test signal with a known waveform is sent to the DUT, and the error of the input data returned and received from the DUT accompanying the transmission of the test signal is detected. The error detection device 1 is characterized by comprising:

[0011] An operation display unit 6 that displays a state transition setting screen 11 of a data flow of the overall state transition including each state 12 based on the communication standard and the state transition conditions 13 executed between the states.

[0012] In the state transition setting screen, input setting of the state transition conditions can be performed.

[0013] The error detection device according to the second aspect of the present invention is characterized in that, in the error detection device according to the first aspect, it comprises:

[0014] For the input box 13a of the state transition conditions in the state transition setting screen, input setting can be performed within a specified adjustment range including values specified by the communication standard.

[0015] The error code detection device according to Scheme 3 of the present invention is characterized in that in the error code detection device of Scheme 2,

[0016] It is possible to select and set a state transition condition 13D that does not exist in the communication standard between the states of the state transition setting screen 11.

[0017] The error code detection device according to Scheme 4 of the present invention is characterized in that in the error code detection device of Scheme 2,

[0018] It is possible to input and set "0" in the input box of the state transition condition 13A in the transmission state or the state transition condition 13B in the reception state.

[0019] The error code detection device according to Scheme 5 of the present invention is characterized in that in the error code detection device of Scheme 2,

[0020] In the state transition setting screen, it is possible to select and set a state transition condition 13D that does not exist in the communication standard between the states.

[0021] The error code detection method according to Scheme 6 of the present invention is in a state where the object under test W is made to transition to a signal return state through a handshake based on a communication standard, and a test signal with a known waveform is sent to the object under test, and the error code of the input data returned and received from the object under test along with the transmission of the test signal is detected. The error code detection method is characterized by further including the following steps:

[0022] Display a state transition setting screen 11 that includes a data stream of the overall state transition based on each state 12 of the communication standard and the state transition conditions 13 executed between the states; and

[0023] In the state transition setting screen, input and set the state transition conditions.

[0024] The error code detection method according to Scheme 7 of the present invention is characterized in that in the error code detection method of Scheme 6,

[0025] For the input box 13a of the state transition condition in the state transition setting screen, it is possible to perform input setting within a specified adjustment range including values specified by the communication standard.

[0026] The error code detection method according to Scheme 8 of the present invention is characterized in that in the error code detection method of Scheme 7, it includes the following steps:

[0027] It is possible to select and set a state transition condition 13D that does not exist in the communication standard between the states of the state transition setting screen 11.

[0028] The error code detection method described in Solution 9 of the present invention is characterized in that in the error code detection method of Solution 7,

[0029] "0" can be set and input in the input box of the state transition condition 13A in the transmission state or the state transition condition 13B in the reception state.

[0030] The error code detection method described in Solution 10 of the present invention is characterized in that in the error code detection method of Solution 7,

[0031] In the state transition setting screen, a state transition condition 13D that does not exist in the communication standard can be selected and set between states.

[0032] According to the present invention, it has any advantages of both the fixed sequence type and the handshake type, and can implement a flexible and easy standard test. As a result, the user can accurately grasp the trend of state transition or the characteristics of defective conditions of the device under test, and thus can carry out smooth development and debugging. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a block diagram of an error code detection device according to the present invention.

[0034] Figure 2 is a diagram showing an example of a state transition setting screen of an error code detection device according to the present invention.

[0035] Figure 3 is a diagram showing another example of a state transition setting screen of an error code detection device according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0036] Hereinafter, modes for implementing the present invention will be described in detail with reference to the drawings.

[0037] The present invention relates to, for example, an error code detection device and an error code detection method that use a handshake type method in which a device equipped with a link training state machine (LTSSM: Link Training & Status State Machine) as a link state management mechanism for managing link states is set as a device under test under a communication standard of a high-speed serial bus such as PCI Express or USB, and the device under test is transitioned to a signal return state (Loopback.Active) by handshake based on the communication standard with the device under test. In addition, LTSSM exists in the physical layer and transitions by observing signals received by the physical layer.

[0038] Moreover, in the error code detection device and error code detection method according to the present invention, in the measurement mode of transitioning to the state (Loopback.Active) of signal return, a test signal with a known waveform is sent to the object under test, and bit errors of the input data returned and received from the object under test along with the transmission of the test signal are detected.

[0039] The object under test W, which is the detection target of the error code detection device 1 of the present embodiment, is equipped with an LTSSM (Wa) for managing the link state. In the training mode of handshake based on the communication standard before error code detection (before error code measurement), it is connected to the error code detection device 1 via a test fixture (not shown), and the detection of this connection starts the transmission of an LFPS (Low Frequency Periodic Signaling) signal.

[0040] In addition, since the interface of the signal output part of the error code detection device 1 is different from the interface of the signal receiving part of the object under test W, the test fixture (not shown) is used for conversion to make these interfaces consistent.

[0041] As Figure 1 shown, the error code detection device 1 of the present embodiment is generally configured to include a waveform generation unit 2, a waveform detection unit 3, an error detection unit 4, a link state management unit 5, an operation display unit 6, a storage unit 7, and a control unit 8.

[0042] The waveform generation unit 2 generates the waveform to be sent to the object under test W. In the training mode for transitioning the LTSSM (Wa) of the object under test W to the signal return state (Loopback.Active), a training waveform signal corresponding to the link state of the LTSSM is generated through control from the control unit 8 via the link state management unit 5.

[0043] In the state where the object under test W has transitioned to the signal return state (Loopback.Active), in the measurement mode of performing the jitter tolerance test of the object under test W, the waveform generation unit 2 generates a known waveform signal input to the object under test W through control from the control unit 8 via the link state management unit 5. The known waveform signal at this time is composed of, for example, a pseudo-random binary sequence based on NRZ (Non Return to Zero) signals of "0" and "1", and is a CP (Compliance pattern: test pattern) of a waveform specified by the communication standard.

[0044] In the training mode, the waveform detection unit 3 detects the training waveform signal sent from the object under test W according to the transition of the state of the LTSSM (Wa) of the object under test W along with the handshake based on the training waveform signal sent from the waveform generation unit 2.

[0045] In the measurement mode where the waveform detection unit 3 is in the state where the object under test W transitions to the signal return state (Loopback.Active), when the waveform signal generated by the waveform generation unit 2 is input to the object under test W, the waveform signal that returns from the object under test W and is input is detected accordingly.

[0046] In the measurement mode, the error detection unit 4 compares the known waveform signal generated by the waveform generation unit 2 as a test signal with the waveform signal that returns from the object under test W and is detected by the waveform detection unit 3 following the transmission of the known waveform signal to detect bit errors.

[0047] The link state management unit 5 includes an LTSSM having the same or equivalent mechanism as the LTSSM (Wa) mounted on the object under test W and operates according to the communication standard of the I / O interface used (e.g., USB3.2 Gen1, USB3.2 Gen2, etc.).

[0048] The link state management unit 5 transitions the link state in the same manner as the LTSSM (Wa) of the object under test W based on the signal for communication with the object under test W and can identify the current link state of the LTSSM (Wa) in the object under test W. Thereby, various information such as the LTSSM value, link speed, presence or absence of loopback, transition waveform of the LTSSM, channel number for identifying a channel, link number, generation time or generation count of the waveform signal, weighting, and adjustment value of the equalizer on the receiving side can be obtained.

[0049] The operation display unit 6 is a user interface including a display unit such as a liquid crystal display and various keys, switches, buttons, and soft keys on the display screen of the display unit included in the error code detection device 1, and operates it when performing various settings or displays related to error code detection.

[0050] Specifically, the operation display unit 6 displays, under the control of the control unit 8 based on the operation of the operation unit, a setting screen related to error code detection, recorded information stored in the storage unit 7, measurement results such as error information detected by the error detection unit 15, etc.

[0051] Moreover, as a display related to the state transition based on the handshake with the object under test W, the operation display unit 6, under the control of the control unit 8 based on the operation of the operation unit, Figure 2 or Figure 3 The state transition setting screen 11 in the shown display mode is displayed on the display screen 6a.

[0052] In the state transition setting screen 11, a data flow graph of the overall state transition including each state (elliptical part showing the name of each state) 12 based on the communication standard and the state transition conditions (rectangular part showing the state transition conditions) 13 executed between the states is displayed on the display screen.

[0053] Here, Figure 2 a state transition setting screen 11 of USB3.2 Gen1 is shown. In Figure 2 the state transition setting screen 11, each state 12 is displayed in the state transition order of "Rx.Detect" → "Polling.LFPS" → "Polling.RxEQ" → "Polling.Active" → "Polling.Configuration" → "Polling.Idle" → "Loopback.Active" from top to bottom of the screen.

[0054] Figure 3 a state transition setting screen 11 of USB3.2 Gen2 is shown. In Figure 3 the state transition setting screen 11, each state 12 is displayed in the state transition order of "Rx.Detect" → "Polling.LFPS" → "Polling.LFPS Plus" → "Polling.Port Match" → "Polling.Port Configuration" → "Polling.RxEQ" → "Polling.Active" → "Polling.Configuration" → "Polling.Idle" → "Loopback.Active" from top to bottom of the screen.

[0055] And, in Figure 2 or Figure 3 the state transition setting screen 11, as the state transition conditions 13 executed between the states, the state transition conditions 13A of the transmission state (PPG Condition) are displayed on the left side of each state 12, the state transition conditions 13B of the reception state (ED Condition) are displayed on the left side of 13A, and the state transition conditions 13C of the timeout setting (Timeout Setting [ms]) are displayed on the right side of each state 12.

[0056] Specifically, in Figure 2In the state transition setting screen 11, regarding the state transition condition 13A for the transmission state, it conforms to "Sent

[16] bursts LFPS", "Sent[4]bursts LFPS", "Sent[65,536]TSEQ", "Sent

[16] TS1OS", and "Sent

[16] TS2 OS". Regarding the state transition condition 13B for the reception state, it conforms to "Received DUT’sLFPS", "Received[2]LFPS", "Received[8]TS1 / TS2OS", and "Received[8]TS2 OS". Regarding the state transition condition 13C for the timeout setting, the

[360] , [12.0], [12.0], [2.0], and [2.0] between "Polling.LFPS", "Polling.RxEQ", "Polling.Active", "Polling.Configuration", "Polling.Idle" and "Rx.Detect" respectively conform to it.

[0057] And, in Figure 3In the state transition setting screen 11, regarding the state transition condition 13A for the transmission state, it matches with "Sent[2]SCD1", "Sent[2]SCD2", "Sent[4]PHY Cap.LBPM", "Sent[4]PHY Ready LBPM", "Sent[524,288]TSEQ", "Sent

[16] TS1 OS", "Sent

[16] TS2 OS". Regarding the state transition condition 13B for the reception state, it matches with "Received DUT’s LFPS", "Received[1]SCD1 / SCD2", "Received[1]SCD2", "Received[2]LBPM", "Received[2]PHY Ready LBPM", "Received[8]TS1 / TS2 OS", "Received[8]TS2OS". Regarding the state transition condition 13C for the timeout setting, the

[360] ,

[360] , [12.0], [12.0], [12.0], [12.0], [2.0] respectively between "Polling.LFPS", "Polling.LFPS Plus", "Polling.Port Match", "Polling.Port Configuration", "Polling.RxEQ", "Polling.Active", "Polling.Configuration", "Polling.Idle" and "Rx.Detect" match with it.

[0058] In addition, the [] of the above-mentioned state transition condition 13A for the transmission state, state transition condition 13B for the reception state, and state transition condition 13C for the timeout setting respectively correspond to the input box 13a described below, and the numbers in the [] represent the values set and input into the input box 13a.

[0059] Figure 2 or Figure 3 The state transition conditions 13 (the state transition condition 13A for the transmission state, the state transition condition 13B for the reception state, the state transition condition 13C for the timeout setting) for each input box 13a can be variably input and set within a specified adjustment range including the values specified by the communication standard. Thus, it is not limited to the fixed values specified by the communication standard, and more delicate input settings can be made.

[0060] For example, in Figure 2 or Figure 3In the state transition setting screen 11, the state transition condition 13B for the received state: "Received[8]TS1 / TS2 OS" means the condition that after continuously receiving TS1 or TS2 eight times in the state of "Polling.Active", it transitions to the next state. However, the user can input and set any value within the range of "from 0 to 65535" in the input box 13a, including the value "8" currently input in the input box 13a as a value specified by the communication standard.

[0061] Moreover, as a setting of 0, as long as "0" is input and set in the input box 13a of the state transition condition 13A in the sending state or the state transition condition 13B in the received state, it is possible to skip this state transition condition and transition to the next state transition condition or the next state. Thus, even in the case of a handshake failure with the DUT W, including the failed state transition condition, by setting 0 for the subsequent state transition conditions, it is possible to quickly transition to the state of "Loopback.Active".

[0062] In addition, when performing a handshake with the DUT W, in the input box 13a of each state transition condition 13, the value specified by the communication standard of the DUT W or the value at the last time a handshake was performed with the DUT W is set as the initial value.

[0063] In the state transition setting screen 11, it is possible to select and set a state transition condition 13D that does not exist in the communication standard between states. For example, in Figure 2 or Figure 3 In the state transition setting screen 11, in the state of "Polling.Active", the state transition condition 13A for the sending state after continuously receiving TS1 or TS2 eight times: "Sent

[16] TS1 OS" corresponds to the state transition condition 13D that does not exist in the communication standard. A check box 13b is provided in the state transition condition 13D that does not exist in this communication standard, and the enable / disable is switched according to whether the check box 13b is checked. Thus, as long as the desired value is set and input in the input box 13a in the state where the check box 13b of the state transition condition 13D that does not exist in the above communication standard is checked, it is possible to extend the time in the state of "Polling.Active" and perform timing adjustment.

[0064] In addition, in Figure 2 or Figure 3In the state transition setting screen 11, a state transition condition 13D that does not exist in the communication standard is added between the state transition condition "Received DUT’s LFPS" in the receiving state and the state "Polling.LFPS", which is "Transition Delay[1]ms", but it is not limited to this. The state transition condition 13D that does not exist in the communication standard can be appropriately added to the position where the state where it is difficult to adjust the timing exists for each communication standard.

[0065] Under the control of the control unit 8, the storage unit 7 stores, as record information corresponding to the transition state of the LTSSM, for example, the transition destination of the link state, the occurrence time of the transition, the trigger for the transition, and error information, etc., managed by the link state management unit 5.

[0066] When performing a handshake or error code detection with the device under test W, the control unit 8 centrally controls each unit (link state management unit 5, operation display unit 6, storage unit 7).

[0067] Specifically, in the training mode, the control unit 8 instructs the waveform generation unit 2 via the link state management unit 5 in such a way that the training waveform signal to be generated next is generated according to the current link state of the LTSSM of the link state management unit 5.

[0068] Moreover, in the measurement mode, the control unit 8 instructs the waveform generation unit 2 via the link state management unit 5 in such a way that a waveform signal is generated.

[0069] Furthermore, the control unit 8 includes a display control mechanism 8a, which controls the reading of the record information corresponding to the transition state of the LTSSM of the link state management unit 5 or the detection result of the error detection unit 4, and performs display control of the read record information or detection result to the operation display unit 6 or Figure 2 or Figure 3 the display control of the state transition setting screen 11 shown.

[0070] Then, when a handshake is performed between the error code detection device 1 configured as above and the device under test W, the error code detection device 1 and the device under test W are connected via a test fixture (not shown).

[0071] If the device under test W detects a connection with the error code detection device 1 via the test fixture, it starts sending the LFPS signal as a training waveform signal.

[0072] The error code detection device 1 transitions to the Polling.LFPS state triggered by the reception of the LFPS signal sent from the device under test W, and starts sending the LFPS signal as a training waveform signal.

[0073] The object under test W makes a transition to the next state triggered by the reception of the LFPS signal sent from the error code detection device 1, and sends a training waveform signal corresponding to the next state.

[0074] Then, when the handshake between the object under test W and the error code detection device 1 is successful, they send the training waveform signals defined in their respective states and make a state transition. The LTSSM of the object under test W finally transitions to the Loopback.Active state for testing.

[0075] Here, when the handshake between the object under test W and the error code detection device 1 fails and does not transition to the Loopback.Active state, in Figure 2 or Figure 3 In the state transition setting screen 11, the values set in the input boxes 13a of the state transition conditions 13 (the state transition condition 13A for the transmission state, the state transition condition 13B for the reception state, and the state transition condition 13C for the timeout setting) that may cause the handshake to fail are adjusted, and the handshake with the object under test W is performed again.

[0076] Moreover, when there is a state where it is difficult to perform timing adjustment according to the communication standard, the check box 13b for the state transition condition 13D that does not exist in the communication standard is checked, and the desired value is set in the input box 13a.

[0077] In the above embodiment, as Figure 1 shown, it is assumed that the error code detection device 1 integrally includes a waveform generation unit 2, a waveform detection unit 3, an error detection unit 4, a link state management unit 5, an operation display unit 6, a storage unit 7, and a control unit 8, but it is not limited to this structure. For example, it can be composed of an external device such as a personal computer connecting the operation display unit 6 to the outside, or the operation display unit 6 can be composed of a module in which the display unit and the operation part are separated, or the waveform generation unit 2 and the waveform detection unit 3 can be modularized separately or set as separate boxes.

[0078] In this way, in the present embodiment, the value input to the input box 13a of the state transition condition 13 defined by the communication standard is not a fixed value but has an adjustment range. And in the state transition setting screen 11, the state transition condition 13D that does not exist in the communication standard can be selectively added by checking the check box 13b. Thereby, it has the advantages of both the fixed sequence type and the handshake type, and thus a flexible and easy standard test can be implemented. As a result, the user can accurately grasp the trend of state transition or the characteristics of abnormal conditions of the object under test, and thus can perform smooth development and debugging.

[0079] As described above, the preferred embodiments of the error detection device and the error detection method according to the present invention have been described. However, the present invention is not limited to the descriptions and drawings based on these embodiments. That is, it is obvious that other embodiments, examples, and application techniques implemented by those skilled in the art according to these embodiments are included in the scope of the present invention.

[0080] Symbol Explanation

[0081] 1 - Error detection device, 2 - Waveform generation unit, 3 - Waveform detection unit, 4 - Error detection unit, 5 - Link state management unit, 6 - Operation display unit, 7 - Storage unit, 8 - Control unit, 8a - Display control mechanism, 11 - State transition setting screen, 12 - State (name of the state), 13 - State transition condition, 13A - State transition condition for the transmission state, 13B - State transition condition for the reception state, 13C - State transition condition for timeout setting, 13D - State transition condition not present in the communication standard, 13a - Input box, 13b - Check box, W - Object under test, Wa - LTSSM.

Claims

1. An error code detection device, which, in a state where the object under test (W) is transitioned to a signal return state through a handshake based on a communication standard between the device and the object under test, sends a test signal with a known waveform to the object under test, and detects an error code of input data returned from and received by the object under test along with the transmission of the test signal. The error code detection device (1) is characterized by comprising: An operation display unit (6) that displays a state transition setting screen (11) of a data flow of an overall state transition including each state (12) based on the communication standard and state transition conditions (13) executed between the states. In the state transition setting screen, input setting of the state transition conditions can be performed. Among them, when "0" is input and set in an input box (13a) for the state transition conditions in the state transition setting screen, the error code detection device skips this state transition condition and transitions to the next state transition condition or the next state.

2. The error code detection device according to claim 1. It is characterized in that The input box (13a) can be input and set within a specified adjustment range including values specified by the communication standard.

3. The error code detection device according to claim 2. It is characterized in that Between the states in the state transition setting screen (11), a state transition condition (13D) that does not exist in the communication standard can be selected and set.

4. The error code detection device according to claim 2. It is characterized in that "0" can be input and set in the input box for the state transition condition (13A) in the transmission state or the state transition condition (13B) in the reception state.

5. The error code detection device according to claim 2. It is characterized in that In the state transition setting screen, between the states, a state transition condition (13D) that does not exist in the communication standard can be selected and set.

6. An error code detection method, which, in a state where the object under test (W) is transitioned to a signal return state through a handshake based on a communication standard between the device and the object under test, sends a test signal with a known waveform to the object under test, and detects an error code of input data returned from and received by the object under test along with the transmission of the test signal. The error code detection method is characterized by further comprising the following steps: Displaying a state transition setting screen (11) of a data flow of an overall state transition including each state (12) based on the communication standard and state transition conditions (13) executed between the states; and In the state transition setting screen, performing input setting of the state transition conditions. Among them, the error code detection method Comprises: When "0" is input and set in an input box (13a) for the state transition conditions in the state transition setting screen, skipping this state transition condition and transitioning to the next state transition condition or the next state.

7. The error code detection method according to claim 6. It is characterized in that The input box (13a) can be input and set within a specified adjustment range including values specified by the communication standard.

8. The error code detection method according to claim 7. It is characterized in that including the following steps: Controlling to be able to select and set a state transition condition (13D) that does not exist in the communication standard between the states of the state transition setting screen (11).

9. The error code detection method according to claim 7, characterized in that, It is possible to input and set "0" in the input box of the state transition condition (13A) in the transmission state or the state transition condition (13B) in the reception state.

10. The error code detection method according to claim 7, characterized in that, In the state transition setting screen, it is possible to select and set a state transition condition (13D) that does not exist in the communication standard between states.

Images