JP3335504B2 - Clock distribution device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clock distribution device, and more particularly, to a clock distribution device in a communication system such as a transmission device in which a redundant configuration is connected by a cable.

With the recent increase in speed and scale of transmission devices, the number of devices composed of a plurality of racks is increasing.

[0002] In an apparatus composed of a plurality of racks, all the racks need to operate with a synchronized clock.
Clocks need to be distributed across the frames. that time,
When trying to make the clock distribution system redundant over the span,
The configuration is as shown in FIG.

That is, the 0-system clock and the 1-system clock are supplied to a clock distribution unit CD0 and a clock distribution unit C, respectively.
D1 and supplied to the clock distribution units CD0 and CD1 to distribute the input clock to two systems in the illustrated example.
A clock is transmitted to four receiving units 10 and 11 via four cables K.

Then, the receiving units 10 and 11 send a normal clock out of the received clocks to the clock selecting unit SEL, and the clock selecting unit SEL selects an optimum clock from the receiving units 10 and 11. And output.

[0005] When a redundant system is constructed in this way, four cables, which normally require only one cable, are required, which inevitably increases the number of cables spanning the bridge, and increases the possibility of erroneous cable connection.

Further, since the device itself operates normally even if a cable is erroneously connected due to the redundant system, it is often unknown until an error occurs once the cable is incorrectly connected. There is no point in having it.

[0007] From such a viewpoint, it is necessary to reliably detect erroneous cable connection.

[0008]

2. Description of the Related Art Conventional devices are small in scale, and there are not many devices constituted by a plurality of racks. Therefore, once the cable is wired during the production of the equipment,
Since then, there has been little rerouting. For this reason, labels were attached to the cables and checked during production to prevent incorrect connection of the cables.

However, in recent years, the number of devices has been increased from a plurality of racks, and clocks have been often distributed between the racks.

[0010] Therefore, it is necessary to connect cables after installing the apparatus in the operation place, and it is difficult to completely prevent erroneous connection only by checking the cable wiring at the time of production as in the related art, and a redundant system configuration is required. It is difficult to determine whether or not the operation is performed normally, which causes a problem of lowering the reliability of the apparatus.

Accordingly, an object of the present invention is to automatically detect an incorrect connection of a clock distribution cable in a device having a redundant configuration in a clock distribution system.

[0012]

In order to achieve the above object, in a clock distribution device according to the present invention, not only a clock but also a frame pulse is transmitted through a cable in a transmission device or the like. It is noted that

Therefore, according to the present invention, there are provided a clock distribution unit of a system 0 and a system 1 for distributing a clock and a frame pulse (FP) to 2N (N is a natural number satisfying N ≧ 2), respectively.
4N receivers for receiving the clock and frame pulse from both clock distributors in pairs of 0 system and 1 system, and 4N receivers for transmitting the clock and frame pulse from both clock distributors to each receiver Assuming that the clock distribution device is composed of the above-described cable, various solutions described below are taken.

[1] In the present invention, each clock distribution unit
A transmitting-side setting unit for setting the distributed 2N frame pulses to a system 0 or system 1 different from the other clock distribution unit;
A polarity inverting unit that inverts the polarities of the 2N frame pulses according to the setting of the transmitting side setting unit, wherein each receiving unit sets a 0 system or a 1 system; A polarity judging unit for judging whether the polarity of the frame pulse from the distributing unit is correct based on the setting of the receiving side setting unit, and generating an alarm signal when the judgment result of the polarity judging unit indicates that the judgment is wrong, And a polarity inverting unit for returning only the frame pulse whose polarity has been inverted based on the setting of the receiving side setting unit and outputting it.

[0015] That is, a 0-system / 1-system clock distribution unit for transmitting a clock and a frame pulse, 2N reception units for receiving a clock and a frame pulse, a clock distribution unit and a reception unit are connected, and a clock and a frame are connected. In a clock distribution device having a redundant system of 0 system / 1 system composed of 4N cables for transmitting pulses, a polarity inverting unit for inverting the polarity of a frame pulse by setting the clock distributing unit of 0 system / 1 system is provided. The receiving unit is provided with a polarity judging unit for judging the polarity of the frame pulse, and the clock distribution unit inverts the polarity of the frame pulse according to whether it is the 0 system or the 1 system and transmits the clock and the frame pulse to the receiving unit. The polarity determining unit of the receiving unit determines the polarity of the frame pulse so that the redundant configuration of the clock distribution device is normally configured. Buru determines whether or not it is connected.

As a result, when it is determined that the cable connection is incorrect, an alarm signal is generated. When it is determined that the cable connection is correct, only the inverted frame pulse from the clock distribution unit is sent to the polarity inversion unit of the reception unit. The polarity is inverted and output.

[2] In the present invention, each clock distribution unit
A transmitting-side setting unit for setting whether or not to invert according to whether the distribution destination is the 0-system or the 1-system; A polarity reversing unit that reverses according to the setting of the setting unit is provided.
A receiving-side setting unit that sets whether the system is 0 or 1; a polarity determining unit that determines whether the polarity of the frame pulse from both clock distribution units is correct based on the setting of the receiving-side setting unit; When the judgment result indicates an error, an alarm signal is generated, and when the judgment result indicates a correct one, the frame pulse whose polarity has been inverted based on the setting of the receiving side setting unit is restored, and the polarity is not inverted. And a polarity inverting unit that outputs the frame pulse as it is.

That is, a polarity inverting unit for inverting the polarity of a frame pulse by setting is provided in the clock distribution unit of the 0 system / 1 system, and a polarity determining unit for determining the frame pulse polarity is provided in the receiving unit. The clock pulse and the frame pulse are transmitted to the receiving unit by inverting the polarity of the frame pulse depending on whether the destination is the 0 system or the 1 system, and the polarity of the frame pulse is determined by the receiving unit. It is determined whether the cable is connected so as to be configured.

As a result, when it is determined that the cable connection is incorrect, an alarm signal is generated. When it is determined that the cable connection is correct, the polarity inverting unit of the receiving unit replaces the frame pulse whose polarity has been inverted with the original one. The frame pulse whose polarity is not inverted is output as it is.

[3] In the present invention, each clock distribution unit
A transmitting-side setting unit for setting the distributed 2N frame pulses to a system 0 or system 1 different from the other clock distribution unit;
A receiving-side setting for setting a pulse width of each of the 2N frame pulses to a predetermined width in accordance with the setting of the transmitting-side setting unit; Unit, a pulse width determination unit that determines whether the pulse width of the frame pulse from both clock distribution units is right or wrong based on the setting of the reception side setting unit, and indicates that the determination result of the pulse width determination unit is incorrect. And a pulse width varying section for returning an output of the pulse width of the frame pulse based on the setting of the receiving side setting section when the alarm signal is generated and indicating correctness.

That is, a 0/1 / system clock distribution unit is provided with a frame pulse width variable unit for setting a frame pulse width to, for example, M bits by setting, and a receiving unit for determining a frame pulse width is determined. The determination unit is provided, and the clock distribution unit changes the width of the frame pulse depending on whether it is the system 0 or 1 and transmits the clock and the frame pulse to the reception unit, and the reception unit determines the width of the frame pulse to determine the clock. It is determined whether or not the cables are connected so that the redundant configuration of the distribution device is normally configured.

As a result, when it is determined that the cable connection is incorrect, an alarm signal is generated, and when it is determined that the cable connection is correct, only the frame pulse whose pulse width is varied from the clock distribution unit is transmitted to the pulse of the reception unit. The pulse width is returned to the original pulse width by the variable width section and output.

[4] In the present invention, each clock distribution unit
A transmitting-side setting unit for setting whether or not to vary the pulse width to a predetermined width depending on whether the distribution destination is the 0-system or the 1-system;
A pulse width varying unit that varies a pulse width of the N frame pulses of the 0 system or the 1 system to a predetermined width according to the setting of the transmission side setting unit, and determines whether each receiving unit is the 0 system or the 1 system. A receiving-side setting unit to be set; a pulse-width determining unit for determining whether the pulse width of the frame pulse from both clock distribution units is correct based on the setting of the receiving-side setting unit; When an alarm signal is generated to indicate that the frame pulse is correct, the frame pulse whose pulse width has been changed based on the setting of the receiving side setting unit is restored, and the frame pulse whose pulse width is not changed is returned. Is characterized by including a pulse width variable section that outputs the pulse width as it is.

That is, a frame pulse width variable section for setting the frame pulse width to, for example, M bits by setting is provided in the 0-system / 1-system clock distribution section, and the frame pulse width for determining the frame pulse width is determined in the receiving section. The determination unit is provided, and the clock distribution unit changes the width of the frame pulse depending on whether the distribution destination is the 0 system or the 1 system, transmits the clock and the frame pulse to the reception unit, and determines the width of the frame pulse by the reception unit. It is determined whether or not the cables are connected so that the redundant configuration of the distribution device is normally configured.

As a result, when it is determined that the cable connection is incorrect, an alarm signal is generated. When it is determined that the cable connection is correct, a frame pulse whose pulse width is varied by the pulse width varying unit of the receiving unit is determined. The pulse width is restored, and the frame pulse whose pulse width is not changed is output as it is.

[5] In the present invention, each clock distribution unit
A transmitting-side setting unit for setting the distributed 2N frame pulses to a system 0 or system 1 different from the other clock distribution unit;
A receiving-side setting unit that includes a pulse width changing unit that changes the period of the 2N frame pulses to a predetermined period in accordance with the setting of the transmitting-side setting unit; A pulse period determining unit that determines whether the frame pulse period from both clock distribution units is correct based on the setting of the receiving-side setting unit; and an alarm when the determination result of the pulse period determining unit is incorrect. And a pulse period reproducing unit for returning the frame pulse period based on the setting of the receiving side setting unit when the signal is generated and indicating that the signal is correct, and outputting the frame pulse.

That is, the 0-system / 1-system clock distribution unit is provided with a frame pulse frequency dividing unit for setting the frame pulse period to, for example, 1 / M by setting, and the receiving unit is provided with a frame pulse period monitoring unit. Department is 0
The clock and the frame pulse are transmitted to the receiving unit by changing the period of the frame pulse depending on whether the system or the system is used, and the receiving unit monitors the period of the frame pulse so that the redundant configuration of the clock distribution device can be configured normally. It is determined whether the cable is connected.

As a result, when it is determined that the cable connection is incorrect, an alarm signal is generated, and when it is determined that the cable connection is correct, only the frame pulse whose pulse period is changed from the clock distribution unit is transmitted to the pulse of the reception unit. The cycle reproduction unit returns the pulse cycle to the original pulse cycle and outputs it.

[6] In the present invention, each clock distribution unit
A transmitting-side setting unit for setting whether the pulse period is changed to a predetermined period depending on whether the distribution destination is the 0 system or the 1 system, and a pulse period of the N frame pulses of the 0 system or the 1 system A pulse period variable unit that varies a predetermined period according to the setting of the transmission side setting unit, wherein each receiving unit sets a 0 system or a 1 system, and a frame from both clock distribution units. A pulse period determining unit that determines whether the pulse period of the pulse is correct based on the setting of the receiving side setting unit, and generates an alarm signal when the determination result of the pulse period determining unit indicates an error, thereby indicating that the pulse period is correct. Sometimes, a pulse period reproducing unit that restores the frame pulse whose pulse period is varied based on the setting of the receiving side setting unit and outputs the frame pulse whose pulse period is not varied as it is. It is characterized in that it comprises.

That is, the clock distribution unit of the system 0 / system 1 is provided with a frame pulse frequency dividing unit for setting the frame pulse period to 1 / M by setting, and the receiving unit and the frame pulse period monitoring unit are provided. The unit changes the period of the frame pulse depending on whether the distribution destination is the 0 system or the 1 system, transmits the clock and the frame pulse to the receiving unit, and monitors the period of the frame pulse in the receiving unit, so that the redundant configuration of the clock distribution device is normal. It is determined whether or not the cable is connected so as to be configured as described above.

As a result, when it is determined that the cable connection is incorrect, an alarm signal is generated, and when it is determined that the cable connection is correct, the frame pulse whose pulse period is varied by the pulse period reproducing unit of the receiving unit is determined. The original pulse cycle is returned, and the frame pulse whose pulse cycle is not changed is output as it is.

[7] In the present invention, each clock distribution unit
A transmitting-side setting unit for setting the distributed 2N frame pulses to a system 0 or system 1 different from the other clock distribution unit;
A signal line switching unit for exchanging the signal line positions of the 2N frame pulses with all the clocks in accordance with the setting of the transmission side setting unit, wherein each receiving unit sets a 0 system or a 1 system; Unit, a signal line determination unit that determines the signal line position of the frame pulse from both clock distribution units based on the setting of the reception side setting unit, and indicates that the determination result of the signal line position determination unit is incorrect. And a signal line position exchange unit for returning the signal line position of the frame pulse to the original position based on the setting of the receiving side setting unit when an alarm signal is generated and indicating correctness.

That is, a clock / frame pulse signal line exchange unit for exchanging the position of a signal line in a cable for a clock and a frame pulse by setting is provided in a clock distribution unit of the 0 system / 1 system. A clock-frame pulse signal line judging unit for judging a clock or a frame pulse is provided. The clock distributing unit exchanges the clock and frame pulse signal line positions depending on whether the system is a 0-system or a 1-system, and sends the clock and frame to the receiving unit. By transmitting a pulse and determining whether the signal transmitted by a specific signal line is a clock or a frame pulse in the receiving unit, the cable is connected so that the redundant configuration of the clock distribution device is normally configured. Has been determined.

As a result, when it is determined that the cable connection is incorrect, an alarm signal is generated, and when it is determined that the cable connection is correct, only the frame pulse whose signal line position is exchanged from the clock distribution unit is received by the reception unit. The signal line position exchange unit returns to the original signal line position and outputs the signal.

[8] In the present invention, each clock distribution unit
A transmitting-side setting unit for setting whether or not the signal line position is variable depending on whether the distribution destination is the 0-system or the 1-system, and a signal-line position of the N frame pulses of the 0-system or the 1-system. A signal line position changing unit that changes the signal line position in accordance with the setting of the transmission side setting unit, wherein each receiving unit sets a 0-system or a 1-system, and a frame pulse signal from both clock distribution units. A signal line position judging unit for judging the correctness of the line position based on the setting of the receiving side setting unit; and when the judgment result of the signal line position judging unit indicates an error, an alarm signal is generated to indicate correctness. A pulse cycle reproducing unit that returns the frame pulse whose signal line position is changed based on the setting of the receiving side setting unit, and outputs the frame pulse whose signal line position is not changed as it is. Specially It is set to.

That is, a clock-frame pulse signal line exchange unit for exchanging the position of a signal line in a cable for a clock and a frame pulse by setting is provided in a clock distribution unit of the system 0 / system 1, and a signal is transmitted to a reception unit. A clock-frame pulse signal line determination unit for determining whether a clock or a frame pulse is provided.
The clock and the frame pulse are transmitted to the receiving unit by exchanging the signal line positions of the clock and the frame pulse depending on the system, and the receiving unit determines whether the signal transmitted by a specific signal line is the clock or the frame pulse. Thus, it is determined whether or not the cable is connected so that the redundant configuration of the clock distribution device is normally configured.

As a result, when it is determined that the cable connection is incorrect, an alarm signal is generated, and when it is determined that the cable connection is correct, the frame pulse in which the signal line position is changed by the signal line position exchange unit of the receiving unit. Is returned to the original signal line position, and the frame pulse whose signal line position is not changed is output as it is.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the above-described clock distribution devices [1] to [8] according to the present invention will be described below with reference to FIGS.

In each embodiment, each of the clock and the frame pulse (FP) is 2N (N is N
0 and 1-system clock distribution units CD0 and CD1 that distribute to ≧ 2 natural numbers, and both clock distribution units CD0 and C
The clock and the frame pulse from D1 are set to 0 system and 1
4N receiving units 10, 1 each receiving in a pair of systems
, N0, N1 and both clock distribution units CD0, CD0,
.., N0, N1 from the CD1 and 4N cables K for transmitting both the clock and the frame pulse.

When 4N cables K are normally connected, the clock distribution unit CD0 outputs the signals from the receiving units 10,
11,..., N0, N1 connection ports 100, 110,.
.., N00, N10 are connected by cables, and the clock distribution unit CD1 receives the respective reception units 10, 11,..., N0,
, N01, N11
Cable is connected.

[1] In this embodiment, the clock-side distribution units CD0 and CD1 have transmission-side setting units 1a0 and 1a, respectively.
1 (not shown) and polarity reversing sections 2a0 and 2a1 (not shown).
11,..., N0, N1 are respectively set to the receiving side setting unit 3a.
10, 3a11, ..., 3aN0 (not shown), 3aN1
(Not shown), and polarity determination units 4a10, 4a11,.
4aN0 (not shown) and 4aN1 (not shown), and polarity reversing parts 5a10, 5a11,..., 5aN0 (not shown) and 5aN1 (not shown) are provided.

Now, it is assumed that a frame pulse of a negative polarity is used for the entire apparatus, and that the polarity inverting units 2a0 and 2a1 for inverting the polarity of the frame pulse use positive polarity as the polarity of the frame pulse for each clock distribution unit. It is determined in advance whether to use the negative polarity.

In this case, the transmitting side setting units 1a0, 1a
By setting 1, the clock distribution unit CD0 uses the negative polarity and the clock distribution unit CD1 uses the positive polarity.
D1 inverts the polarity of the frame pulse and transmits the clock and the frame pulse to the receiving unit. Of course, the setting units 1a0 and 1a1 may be set in reverse.

Each of the receiving units 10, 11,..., N0, N1
In the receiving unit 10, for example, if the polarity of the frame pulse at the connection port 100 is positive and the polarity of the frame pulse at the connection port 101 is negative, the polarity determination unit 4a10
Recognizes that the cable is normally connected based on the setting of the receiving side setting unit 3a10 corresponding to the transmitting side setting unit 1a0, 1a1, and generates an alarm signal if the polarity is different. Thereby, erroneous connection of the cable can be detected. The same applies to the other receiving units 11,..., N1.

When the polarity judging unit 4a10 recognizes that the cable is correctly connected, the polarity reversing unit 5a10
Also inverts the polarity of only the frame pulse from the clock distribution unit CD1 to the receiving port 101 based on the setting of the receiving side setting unit 3a10 and outputs the frame pulse together with the clock.

[2] In this embodiment, the clock distribution units CD0 and CD1 have the transmission side setting units 1b0 and 1b respectively.
1 (not shown) and polarity reversing units 2b0 and 2b1 (not shown).
,..., N0 and N1 are respectively set to the receiving side setting unit 3b.
, 3bN0 (not shown), 3bN1
(Not shown), and polarity determining units 4b10, 4b11,.
4bN0 (not shown) and 4bN1 (not shown), and polarity reversing parts 5b10, 5b11,..., 5bN0 (not shown) and 5bN1 (not shown) are provided.

The polarity reversing units 2b0 and 2b1 in the clock distribution units CD0 and CD1 are provided with the setting units 1b0 and 1b.
Under the control of 1, the same operation is performed, and half of N frame pulses out of 2N output frame pulses are inverted and output. In the illustrated example, polarity non-inversion and polarity inversion are alternately distributed. Of course, the setting units 1b0 and 1b1 may be set in reverse.

Each of the receiving units 10, 11,..., N0, N1
In the receiving unit 10, for example, if the polarity of the frame pulse at the connection port 100 and the polarity of the frame pulse at the connection port 101 are both positive (or negative), the polarity determination unit 4
b10 recognizes that the cable is normally connected based on the setting of the receiving side setting section 3b10 set corresponding to the transmitting side setting sections 1b0 and 1b1, and sends it to the polarity reversing section 5b10 as it is, In the part 5b10, it passes straight through.

On the other hand, if the polarities are different from each other, an erroneous connection of the cable can be detected by generating an alarm signal.

In the receiving section 11, if the polarity of the frame pulse at the connection port 110 and the polarity of the frame pulse at the connection port 111 are both negative (or positive), the polarity determination section 4
b11 recognizes that the cable is normally connected based on the setting of the receiving side setting unit 3b11 corresponding to the transmitting side setting units 1b0 and 1b1, and sends it to the polarity reversing unit 5b10 as it is, In the section 5b10, the polarity of both frame pulses is inverted and output.

Similarly, the non-inversion or inversion of the frame pulse is performed in the other receiving units.

[3] In this embodiment, the transmission side setting units 1c0, 1c are provided in the clock distribution units CD0, CD1, respectively.
1 (not shown) and variable pulse width units 2c0 and 2c1 (not shown).
, N0, N1 are respectively set to the receiving side setting units 3c10, 3c11,..., 3cN0 (not shown), 3c
N1 (not shown) and pulse width determination units 4c10 and 4c1
1,..., 4cN0 (not shown), 4cN1 (not shown)
, 5cN0
(Not shown) and 5cN1 (not shown).

Now, suppose that a frame pulse of 1 bit width is used for the entire apparatus, and the pulse width of the frame pulse is 2
Which of the pulse width variable units 2c0 and 2c1 to be expanded to bits is used is determined in advance for each clock distribution unit.

Here, it is assumed that the clock distribution unit CD0 transmits data using a 1-bit width frame pulse and the clock distribution unit CD1 transmits data using a 2-bit width frame pulse according to the settings of the transmission side setting units 1c0 and 1c1. Of course, the setting units 1c0 and 1c1 may be set in reverse.

.., N0, N1
In the receiving unit 10, for example, the pulse width of the frame pulse at the connection port 100 is 1 bit width and the connection port 10
If the pulse width of one frame pulse is 2 bits wide, the pulse width determination unit 4c10 sets the transmission side setting units 1c0 and 1c1.
Erroneous connection of the cable is detected by recognizing that the cable is normally connected based on the setting of the receiving side setting unit 3c10 corresponding to the above, and generating an alarm signal if the pulse width is different. it can. The same applies to the other receiving units 11,..., N1.

When the pulse width determination unit 4c10 recognizes that the cable is correctly connected, the pulse width variable unit 5c10 also controls only the frame pulse from the clock distribution unit CD1 to the reception port 101 based on the setting of the reception side setting unit 3c10. Is returned to the 1-bit pulse width and output together with the clock.

[4] In this embodiment, the clock distribution units CD0 and CD1 have the transmission side setting units 1d0 and 1d respectively.
1 (not shown) and variable pulse width units 2d0 and 2d1 (not shown).
, N0, and N1, respectively, receive side setting units 3d10, 3d11,..., 3dN0 (not shown), 3d
N1 (not shown) and pulse width determination units 4d10 and 4d1
1,..., 4dN0 (not shown), 4dN1 (not shown)
, 5dN0
(Not shown) and 5dN1 (not shown).

The pulse width variable units 2d0 and 2d1 in the clock distribution units CD0 and CD1 are provided with setting units 1d0, 2d0.
Under the control of 1d1, both perform the same operation, and 2N
Among the output frame pulses, half the N frame pulses are output with variable pulse width. In the illustrated example, the pulse width is alternately distributed between a 1-bit width and a 2-bit width. Of course, the setting units 1d0 and 1d1 may be set in reverse.

Each of the receiving units 10, 11,..., N0, N1
For example, in the receiving unit 10, if the pulse width of the frame pulse at the connection port 100 and the pulse width of the frame pulse at the connection port 101 are both 1-bit width, the pulse width determination unit 4d10 sets the transmission-side setting units 1d0 and 1d1. It is recognized that the cable is normally connected based on the setting of the receiving side setting unit 3d10 corresponding to the above, and is sent to the pulse width variable unit 5d10 as it is.
Then pass it.

On the other hand, if the pulse widths are different from each other, an erroneous connection of the cable can be detected by generating an alarm signal.

In the receiving section 11, if the pulse width of the frame pulse at the connection port 110 and the pulse width of the frame pulse at the connection port 111 are both 2 bits, the pulse width determination section 4d11 sets the transmission side setting section 1d0, Based on the setting of the receiving side setting unit 3d11 set corresponding to 1d1, it is recognized that the cable is normally connected, and sent to the pulse width variable unit 5d10 as it is, and the pulse width variable unit 5d10 is sent.
In both cases, both frame pulses are output with the pulse width returned to 1 bit width.

Similarly, the non-inversion or inversion of the frame pulse is performed in the other receiving units.

[5] In this embodiment, the transmission side setting units 1e0 and 1e are provided in the clock distribution units CD0 and CD1, respectively.
1 (not shown) and frame pulse dividers 2e0 and 2e1
(Not shown), and the 4N receiving units 10, 11,..., N0, N1 are respectively provided with receiving-side setting units 3e10, 3e11,.
3eN1 (not shown) and a pulse period determination unit 4e10,
, 4eN0 (not shown), 4eN1 (not shown), and frame pulse reproducing units 5e10, 5e11, ..., 5eN0 comprising a counter and a decoding unit.
(Not shown) and 5eN1 (not shown).

Now, suppose that the pulse period of the frame pulse is divided into 1 / M and used at a frequency FHz as a whole device.
How many Hz is used as the period of the frame pulse is determined in advance for each clock distribution unit.

The clock distribution unit CD0 uses 1 / M frequency division at FHz and the clock distribution unit CD1 uses F / 2 Hz frame pulse at 2 / M frequency division according to the settings of the transmission side setting units 1e0 and 1e1. Shall be transmitted.
Of course, the setting units 1e0 and 1e1 may be set in reverse.

Each of the receiving units 10, 11,..., N0, N1
For example, in the receiving unit 10, if the pulse cycle of the frame pulse at the connection port 100 is FHz and the pulse cycle of the frame pulse at the connection port 101 is F / 2 Hz, the pulse cycle determination unit 4e10 sets the transmission-side setting unit 1e0 , 1e1, it is recognized that the cable is properly connected based on the setting of the receiving side setting unit 3e10, and if the pulse cycle is different, an alarm signal is generated, thereby erroneously connecting the cable. Can be detected. The same applies to the other receiving units 11,..., N1.

When the pulse period determining unit 4e10 recognizes that the cable is correctly connected, the frame pulse dividing unit 5e10 also transmits the frame pulse from the clock distribution unit CD1 to the receiving port 101 based on the setting of the receiving side setting unit 3e10. Only the frequency is divided by 2 to return to the original pulse period and output together with the clock.

[6] In this embodiment, the transmission side setting sections 1f0, 1f are provided in the clock distribution sections CD0, CD1, respectively.
1 (not shown) and frame pulse dividers 2f0, 2f1
(Not shown), and the 4N receiving units 10, 11,..., N0, N1 are respectively provided with receiving-side setting units 3f10, 3f11,.
3fN1 (not shown) and a pulse period determination unit 4f10,
, 4fN0 (not shown), 4fN1 (not shown), and frame pulse reproducing units 5f10, 5f11,.
, 5fN0 (not shown) and 5fN1 (not shown).

The frame pulse dividers 2f0 and 2f1 in the clock distributors CD0 and CD1 are provided with the setting unit 1
Under the control of f0 and 1f1, the same operation is performed, and half of N frame pulses out of 2N output frame pulses are divided by two and output. In the illustrated example, the pulse cycle is alternately distributed between FHz and F / 2 Hz. Of course, the setting units 1f0 and 1f1 may be set in reverse.

Each of the receiving units 10, 11,..., N0, N1
In the receiving unit 10, for example, if the pulse cycle of the frame pulse at the connection port 100 and the pulse cycle of the frame pulse at the connection port 101 are both FHz, the pulse cycle determination unit 4f10 corresponds to the transmission-side setting units 1f0 and 1f1. It recognizes that the cable is normally connected based on the setting of the receiving-side setting unit 3f10 set as above, and sends it to the frame pulse reproducing unit 5f10 as it is, and the frame pulse reproducing unit 5f10 passes through.

On the other hand, if the pulse periods are different from each other, an erroneous connection of the cable can be detected by generating an alarm signal.

In the receiving section 11, if both the pulse cycle of the frame pulse at the connection port 110 and the pulse cycle of the frame pulse at the connection port 111 are F / 2 Hz, the pulse cycle determination section 4f11 sets the transmission-side setting section 1f0, Based on the setting of the receiving side setting unit 3f11 set corresponding to 1f1, it is recognized that the cable is normally connected, and is sent to the frame pulse reproducing unit 5f10 as it is. The pulse cycle is divided by 2 and returned to its original state and output.

In other receiving units, non-inversion or inversion of the frame pulse is similarly performed.

[7] In this embodiment, the transmission side setting units 1g0, 1g are provided in the clock distribution units CD0, CD1, respectively.
1 (not shown) and clock-frame pulse signal line position exchange units 2g0 and 2g1 (not shown), and 4N receiving units 10, 11,..., N0, N1
, Respectively, the receiving side setting units 3g10, 3g11,.
3gN0 (not shown), 3gN1 (not shown), signal line position determination units 4g10, 4g11,..., 4gN0 (not shown), 4gN1 (not shown), and a signal composed of a counter and a decoding unit Line position exchange unit 5g10,5g1
1,..., 5gN0 (not shown), 5gN1 (not shown)
Are provided.

Now, the position of the signal line of the clock and the position of the signal line of the frame pulse in the entire apparatus are determined in advance for each clock distribution unit.

Then, according to the settings of the transmission side setting units 1g0 and 1g1, the clock distribution unit CD0 does not exchange (non-exchange) the signal lines, and the clock distribution unit CD1 exchanges the signal line positions for transmission. . Of course, the setting units 1g0 and 1g1 may be set in reverse.

Each of the receiving units 10, 11,..., N0, N1
For example, in the receiving unit 10, if the signal line position of the frame pulse at the connection port 100 and the signal line position of the frame pulse at the connection port 101 are the same, the signal line position determination unit 4g
10 recognizes that the cable is normally connected based on the setting of the receiving side setting section 3g10 set corresponding to the transmitting side setting sections 1g0 and 1g1, and outputs an alarm signal if the signal line position is different. Due to the occurrence, erroneous connection of the cable can be detected. Other receiving units 11, ...,
The same applies to N1.

When the signal line position determining unit 4g10 recognizes that the cable is correctly connected, the signal line position exchanging unit 5g10 also transmits the frame from the clock distribution unit CD1 to the receiving port 101 based on the setting of the receiving side setting unit 3g10. The signal line position of only the pulse is returned to the original position and output together with the clock.

[8] In this embodiment, the clock distribution units CD0 and CD1 have the transmission side setting units 1h0 and 1h, respectively.
1 (not shown) and signal line position exchange units 2h0 and 2h1 (not shown), and 4N receiving units 1
, N0, N1 are respectively set to the receiving side setting units 3h10, 3h11, ..., 3hN0 (not shown), 3h
N1 (not shown) and signal line position determination units 4h10, 4h
, 4hN0 (not shown), 4hN1 (not shown), and signal line position exchange units 5h10, 5h11,.
hN0 (not shown) and 5hN1 (not shown).

The signal line position exchange units 2h0 and 2h1 in the clock distribution units CD0 and CD1 are provided with the setting unit 1h
Under the control of 0, 1h1, the same operation is performed, and half of N frame pulses out of 2N output frame pulses are output by exchanging signal line positions. In the illustrated example, the signal line positions are alternately distributed so as to be non-exchangeable and exchangeable. Of course, the setting units 1h0 and 1h1 may be set in reverse.

Each of the receiving units 10, 11,..., N0, N1
For example, in the receiving unit 10, if the signal line position of the frame pulse at the connection port 100 and the signal line position of the frame pulse at the connection port 101 are both the same without non-exchange, the signal line position determination unit 4h10 Based on the setting of the receiving side setting unit 3h10 set corresponding to the units 1h0 and 1h1, it is recognized that the cable is normally connected, and is sent to the signal line position exchanging unit 5h10 as it is. Then pass it.

On the other hand, if the signal line positions are different from each other, an erroneous connection of the cable can be detected by generating an alarm signal.

In the receiving section 11, if both the signal line position of the frame pulse at the connection port 110 and the signal line position of the frame pulse at the connection port 111 are the same through exchange, the signal line position determination section 4h11 sets the transmission side. Based on the setting of the receiving side setting unit 3h11 set corresponding to the units 1h0 and 1h1, it recognizes that the cable is normally connected and sends it to the signal line position exchanging unit 5h10 as it is. In both cases, the signal line positions are exchanged for both frame pulses, and the signals are returned to the original position and output.

In other receiving units, non-inversion or inversion of the frame pulse is similarly performed.

[0085]

As described above, according to the clock distribution apparatus according to the present invention, a clock distribution apparatus having a 1 + 1 redundant configuration and distributing a clock and a frame pulse by a cable is a system 0 or 1 or both systems. Each time the frame pulse is modulated, and the modulated characteristic is detected by each receiving unit connected to the cable from the distribution destination, thereby detecting an erroneous connection of the cable and generating an alarm. When there is no misconnection, the output is returned to the state before modulation, so that even if the number of cables increases, it is possible to automatically detect the misconnection of the cable without requiring labeling or the like. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment (1) of a clock distribution device according to the present invention.

FIG. 2 is a block diagram showing an embodiment (2) of a clock distribution device according to the present invention.

FIG. 3 is a block diagram showing an embodiment (3) of a clock distribution device according to the present invention.

FIG. 4 is a block diagram showing an embodiment (4) of a clock distribution device according to the present invention.

FIG. 5 is a block diagram showing an embodiment (5) of a clock distribution device according to the present invention.

FIG. 6 is a block diagram showing an embodiment (6) of a clock distribution device according to the present invention.

FIG. 7 is a block diagram showing an embodiment (7) of a clock distribution device according to the present invention.

FIG. 8 is a block diagram showing an embodiment (8) of a clock distribution device according to the present invention.

FIG. 9 is a block diagram illustrating a configuration example of a general redundant clock distribution device.

[Explanation of symbols]

CD0, CD1 Clock distribution unit K cable 10, 11,..., N0, N1 Receiving unit 1a0 to 1h0 Transmitting side setting unit 2a0, 2b0 Polarity inverting unit 3a10, 3a11, to 3h10, 3h11, ... Receiving side setting unit 4a10, 4a11, 4b10, 4b11 Polarity determination unit 5a10, 5a11, 5b10, 5b11 Polarity inversion unit 2c0, 2d0 Pulse width variable unit 4c10, 4c11, 4d10, 4d11 Pulse width determination unit 5c10, 5c11, 5d10, 5d11 Pulse width variable unit 2e0, 2f0 Peripheral part 4e10, 4e11, 4f10, 4f11 Pulse period determination part 5e10, 5e11, 5f10, 5f11 Pulse reproduction transformation part 2g0, 2h0 Signal line position exchange part 4g10, 4g11, 4h10, 4h11 Signal line position determination part 5g10, 5g11, 5h During 0,5h11 signal line position exchange section view, the same reference numerals denote the same or corresponding parts.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04L 7/00

Claims (8)

(57) [Claims] 1. A system which distributes a clock and a frame pulse to 2N (N is a natural number satisfying N ≧ 2) and 0 system and 1 system, respectively.
System clock distribution unit, 4N reception units that receive the clock and frame pulse from both clock distribution units in pairs of system 0 and system 1, respectively. 4N transmitting frame pulse
A clock distribution device comprising: a transmission cable setting unit configured to set the distributed 2N frame pulses to a system 0 or a system different from that of the other clock distribution unit. A polarity inverting unit that inverts the polarities of the 2N frame pulses according to the setting of the transmitting side setting unit, wherein each receiving unit sets a 0-system or a 1-system.
A polarity judging unit for judging the polarity of the frame pulse from both clock distribution units based on the setting of the receiving side setting unit, and an alarm signal is generated when the judgment result of the polarity judging unit indicates an error. A clock inverting unit for returning only the frame pulse whose polarity has been inverted based on the setting of the receiving side setting unit and outputting the frame pulse when the correctness is indicated. 2. The 0 system and the 1 system, each of which distributes a clock and a frame pulse to 2N (N is a natural number satisfying N ≧ 2).
System clock distribution unit, 4N reception units that receive the clock and frame pulse from both clock distribution units in pairs of system 0 and system 1, respectively. 4N transmitting frame pulse
A clock setting device comprising: a transmission side setting unit configured to set whether or not each clock distribution unit is inverted according to whether the distribution destination is the 0 system or the 1 system; The distribution destination is provided with a polarity inverting unit that inverts the polarity of the N frame pulses of the 0-system or the 1-system according to the setting of the transmission-side setting unit, and sets each receiving unit to the 0-system or the 1-system. A receiving side setting unit,
A polarity judging unit for judging the polarity of the frame pulse from both clock distribution units based on the setting of the receiving side setting unit, and an alarm signal is generated when the judgment result of the polarity judging unit indicates an error. A polarity inverting unit is provided for returning the frame pulse whose polarity has been inverted based on the setting of the receiving side setting unit when it indicates that it is correct, and outputting the frame pulse whose polarity has not been inverted as it is. A clock distribution device characterized in that: 3. The 0 system and the 1 system, each of which distributes a clock and a frame pulse to 2N (N is a natural number satisfying N ≧ 2).
System clock distribution unit, 4N reception units that receive the clock and frame pulse from both clock distribution units in pairs of system 0 and system 1, respectively. 4N transmitting frame pulse
A clock distribution device comprising: a transmission cable setting unit configured to set the distributed 2N frame pulses to a system 0 or a system different from that of the other clock distribution unit. And a pulse width variable unit that changes the pulse width of the 2N frame pulses to a predetermined width in accordance with the setting of the transmission-side setting unit, wherein each receiving unit sets a 0-system or a 1-system. Side setting part,
A pulse width determination unit that determines whether the pulse width of the frame pulse from both clock distribution units is correct based on the setting of the receiving side setting unit, and an alarm signal when the determination result of the pulse width determination unit indicates that the determination result is incorrect. And a pulse width variable unit that restores the pulse width of the frame pulse to the original value based on the setting of the receiving side setting unit and outputs the frame pulse when it indicates that it is correct. 4. The 0 system and the 1 system, each of which distributes a clock and a frame pulse to 2N (N is a natural number satisfying N ≧ 2).
System clock distribution unit, 4N reception units that receive the clock and frame pulse from both clock distribution units in pairs of system 0 and system 1, respectively. 4N transmitting frame pulse
A clock distribution device comprising a plurality of cables, wherein each clock distribution unit sets whether or not to vary a pulse width to a predetermined width depending on whether the distribution destination is a 0-system or a 1-system. A transmitting-side setting unit; and a pulse-width changing unit that changes a pulse width of the N frame pulses of the 0-system or the 1-system to a predetermined width according to the setting of the transmitting-side setting unit. A receiving side setting unit for setting whether the system is a system or a system,
A pulse width determination unit that determines whether the pulse width of the frame pulse from both clock distribution units is correct based on the setting of the receiving side setting unit, and an alarm signal when the determination result of the pulse width determination unit indicates that the determination result is incorrect. Is generated to indicate that it is correct, the frame pulse whose pulse width is varied based on the setting of the receiving side setting unit is restored, and the frame pulse whose pulse width is not varied is output as it is. And a clock distribution device. 5. The system 0 and the system 1 for respectively distributing clock and frame pulses to 2N (N is a natural number satisfying N ≧ 2).
System clock distribution unit, 4N reception units that receive the clock and frame pulse from both clock distribution units in pairs of system 0 and system 1, respectively. 4N transmitting frame pulse
A clock distribution device comprising: a transmission cable setting unit configured to set the distributed 2N frame pulses to a system 0 or a system different from that of the other clock distribution unit. And a pulse width variable unit that changes the period of the 2N frame pulses to a predetermined period in accordance with the setting of the transmitting side setting unit, wherein each receiving unit sets a 0 system or a 1 system. A setting section,
A pulse period determination unit that determines whether the period of the frame pulse from both clock distribution units is correct based on the setting of the reception side setting unit, and an alarm signal when the determination result of the pulse period determination unit indicates that the determination result is incorrect. A clock distribution device, comprising: a pulse period reproducing unit that, when generated and indicates correctness, restores and outputs the frame pulse period based on the setting of the receiving side setting unit. 6. A system 0 and a system 1 for respectively distributing a clock and a frame pulse to 2N (N is a natural number satisfying N ≧ 2).
System clock distribution unit, 4N reception units that receive the clock and frame pulse from both clock distribution units in pairs of system 0 and system 1, respectively. 4N transmitting frame pulse
A clock distribution device comprising a plurality of cables, wherein each clock distribution unit sets whether or not to vary a pulse period to a predetermined period depending on whether the distribution destination is the 0 system or the 1 system. A transmission-side setting unit; and a pulse period variable unit that changes a pulse period of the N frame pulses of the 0-system or the 1-system to a predetermined period according to the setting of the transmission-side setting unit. A receiving side setting unit for setting whether the system is a system or a system,
A pulse period determining unit that determines whether the pulse period of the frame pulse from both clock distribution units is correct based on the setting of the receiving side setting unit; and an alarm signal when the determination result of the pulse period determining unit indicates that the determination result is incorrect. Is generated, the frame pulse whose pulse period is changed based on the setting of the receiving side setting unit is restored, and the frame pulse whose pulse period is not changed is output as it is. And a clock distribution device. 7. A system 0 and a system 1 for respectively distributing clock and frame pulses to 2N (N is a natural number satisfying N ≧ 2).
System clock distribution unit, 4N reception units that receive the clock and frame pulse from both clock distribution units in pairs of system 0 and system 1, respectively. 4N transmitting frame pulse
A clock distribution device comprising: a transmission cable setting unit configured to set the distributed 2N frame pulses to a system 0 or a system different from that of the other clock distribution unit. And a signal line exchange unit for exchanging the signal line positions of the 2N frame pulses with all clocks in accordance with the setting of the transmission side setting unit, wherein each receiving unit sets a 0 system or a 1 system. Side setting part,
A signal line determination unit that determines the signal line position of the frame pulse from both clock distribution units based on the setting of the reception side setting unit; and an alarm signal when the determination result of the signal line position determination unit indicates that the determination result is incorrect. And a signal line position exchanging section for returning the signal line position of the frame pulse to the original position based on the setting of the receiving side setting section and outputting the frame pulse based on the setting of the receiving side setting section. 8. A system 0 and a system 1 for respectively distributing a clock and a frame pulse to 2N (N is a natural number satisfying N ≧ 2).
System clock distribution unit, 4N reception units that receive the clock and frame pulse from both clock distribution units in pairs of system 0 and system 1, respectively. 4N transmitting frame pulse
A clock distribution device comprising: a transmission line for setting whether a signal line position is variable depending on whether the distribution destination is a system 0 or a system 1; A setting unit, and a signal line position changing unit that changes the signal line position of the N frame pulses of the 0-system or the 1-system according to the setting of the transmission-side setting unit. A receiving side setting unit for setting the system
A signal line position determining unit that determines whether the signal line position of the frame pulse from both clock distribution units is correct based on the setting of the receiving side setting unit, and indicates that the determination result of the signal line position determining unit is incorrect. Sometimes, when an alarm signal is generated to indicate correctness, the frame pulse whose signal line position has been changed based on the setting of the receiving side setting unit is restored, and the frame pulse whose signal line position has not been changed remains unchanged. A clock distribution device, comprising: a pulse period reproducing unit for outputting.