JP2586804B2 - Data switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data switching device ,
In particular, it relates to a serial data switching device.

[0002]

2. Description of the Related Art Conventionally, in this type of switching device, serial or parallel data and data are switched by a data switching unit 6, as shown in FIG. here,
The data switching unit 6 uses a mechanical relay or an electronic relay.

The data switching instruction in the data switching section 6 is controlled by an external switching control signal. For example, when an external switching control signal is input while data is selected by the data switching unit 6, the data switching unit 6 operates a mechanical relay or an electronic relay to switch to data.

[0004]

In the above-described conventional switching device, data is switched by a mechanical relay or an electronic relay. Therefore, continuous data always loses data during the switching sequence. I have.

[0005] Further, after the data loss is detected, data switching is performed by an external switching control signal.
There is a problem in that the time of data loss becomes longer, and the meaning of making data redundant in a system requiring high reliability is reduced by half.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a data switching method capable of performing data redundancy switching in a system requiring high reliability without data loss.
It is to provide a device .

[0007]

SUMMARY OF THE INVENTION Data switching according to the present invention
The apparatus includes first and second conversion means for converting external serial data into parallel data, and the first and second conversion means.
First and second storage means for temporarily storing the parallel data from the conversion means, and the first and second conversion means
First count up every time conversion is performed in
And a second address counter, and the first and second addresses.
1 and 2 based on the count value of the
Controlling the reading of the parallel data from the storage means.
First and second read control means, and the first and second read control means.
Switching means for selecting and outputting one of the parallel data read from the first and second storage means under the control of the output control means; and the first and second conversion means. When a failure of the serial data to one of the first and second conversion means is detected.
A corresponding address instruction means for instructing a previous address to which the fault occurs in the read control means, said first and second based on the address indicated by the address indication means
Switching instruction means for instructing the switching means to select parallel data read from the storage means corresponding to the other of the two conversion means .

[0008]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. In the figure, serial-parallel conversion units 10 and 20 of data storage units 1 and 2 perform serial-to-parallel conversion of input data, and
Output to 1. The memories 11 and 21 temporarily store the parallel data sent from the serial-parallel converters 10 and 20.

The address counters 12, 22 are serial-
Each time the parallel / parallel converters 10 and 20 perform serial / parallel conversion, they count up, and use the count value as an address for the data readout controllers 13 and 23 and the data loss detector 40 and the address backdater 41 of the address controller 4. 42.

The data read control units 13 and 23 include address counters 12 and 22 and an address back date unit 41,
Reading of parallel data from the memories 11 and 21 is controlled based on the address from the memory.

The data switching unit 3 responds to a switching instruction from the switching control unit 45 of the address control unit 4 to store data in the data storage units 1 and 2.
Of the parallel data from the memories 11 and 21, and outputs the selected parallel data to the data output unit 5.

Data loss detecting section 40 of address control section 4
Detects data loss in data input to the data storage units 1 and 2 based on current addresses from the address counters 12 and 22 of the data storage units 1 and 2. That is, the data loss detection unit 40 is configured to use the address counter 1
Monitor the address count-up at 2,22,
Determine the status of data loss.

Address backdate units 41 and 42 backdate the current address from address counters 12 and 22 in response to the failure information from OR gates 43 and 44, and read the backdate address into data read control unit 1.
Output to 3,23.

That is, the address backdate section 41,
Reference numeral 42 generates an address before the occurrence of the failure in the data storage units 1 and 2 based on the back-date of the current address from the address counters 12 and 22, and outputs the address before the occurrence of the failure to the data read control units 13 and 23.

The OR gates 43 and 44 take the logical sum of the data loss detection signal from the data loss detection unit 40 and the external failure status, and output the operation result to the address backdate units 41 and 42 as failure information.

The switching control unit 45 generates a switching instruction according to the backdate information from the address backdate units 41 and 42 and outputs the switching instruction to the data switching unit 3. That is, the switching control unit 45 includes the address backdate unit 41,
When information indicating that the back date has been input is input from the data switch unit 42, the data switching unit 3 switches to the parallel data from the data storage units 1 and 2 corresponding to the address back date units 41 and 42 that have performed the back date. Output a switching instruction.

The data output unit 5 converts the parallel data from the data storage units 1 and 2 selected by the data switching unit 3 into serial data, and converts the serial data (SELECT).
EDDATA) is output to the outside.

The operation of one embodiment of the present invention will be specifically described with reference to FIG. Hereinafter, a case where data loss has occurred in the data input to the data storage unit 1 while the data switching unit 3 is selecting parallel data from the data storage unit 1 will be described.

The data loss detection section 40 detects that the address counter 12 has stopped counting up at address 100 and, when judging that the data is lost, sends a data loss detection signal to the address backdating section 42 via the OR gate 44. Output.

At this time, assuming that the address counter 22 continues counting up without being stopped, the address backdating section 42
2 is backdated and the address before the data loss is output to the data read control unit 23.

In this case, assuming that the address counter 22 outputs the address 100 similarly to the address counter 12, the address backdating section 42 performs the backdating to the data three addresses before the data at the address 100 by 100.
Address 3 is subtracted from the address, and address 97 is output to data read control unit 23.

When the switching control unit 45 learns from the information from the address backdating unit 42 that the data from the data storage unit 2 has been backdateted to the data three immediately before, the switching control unit 45 informs the data switching unit 3 of the data storage unit 1. An instruction to switch from data to data in the data storage unit 2 is issued.

The data read control unit 23 receives the address 97 before the data loss from the address backdate unit 42.
When an address is input, control is performed so that data is read from address 97 of the memory 21 and output to the data switching unit 3.

The data switching unit 3 operates so as to select data from the data storage unit 2 when outputting data at address 97 to the data output unit 5 in accordance with an instruction from the switching control unit 45.

As a result, even if data loss occurs in the data input to address 100 of data storage unit 1, the data input to data storage unit 2 from address 97 before the data loss occurs in data switching unit 3. Will be selected.

In the above-described processing operation, the data input to the data storage units 1 and 2 by the data loss detection unit 40,
This is a processing operation when data loss is detected. On the other hand, even when a failure is detected externally by serial data from the data output unit 5 and a failure status is input to the address control unit 4 from outside, the data readout destination is set to the data switching unit 3. Can be switched. Since the control in that case is the same as the above-described processing operation, the description is omitted.

When no data loss or failure occurs, the data in the data storage unit 1 or the data in the data storage unit 2 selected by the data switching unit 3 is continuously output to the outside.

As described above, the serial data of the two systems is converted by the serial-parallel converters 10 and 20 and then temporarily stored in the memories 11 and 21. When the failure is detected by the data loss detection unit 40 or a failure due to data in the data storage units 1 and 2 is notified by a failure status from the outside, before the failure generated by the address backdating units 41 and 42 occurs The data switching unit 3 automatically switches the data read out from the normal data storage units 1 and 2 to the data read out based on the address and outputs the data. Can be sent out. Therefore,
Redundant switching of continuous data in a system requiring high reliability can be performed without data loss.

[0030]

As described above, according to the present invention, external serial data is converted into parallel data and temporarily stored in the first and second storage means. When a serial data failure in one of them is detected, the other of the first and second storage means is instructed to the address before the failure occurred, and the first and second storage means are used to determine the first and second addresses based on the designated address. By switching to the parallel data output from the other of the second storage means, there is an effect that data redundancy switching in a system requiring high reliability can be performed without data loss.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a conventional example.

[Explanation of symbols]

 1, 2 data storage unit 3 data switching unit 4 address control unit 5 data output unit 10, 20 serial-parallel conversion unit 11, 21 memory 12, 22 address counter 13, 23 data read control unit 40 data loss detection unit 41, 42 Address backdating part 45 Switching control part

Claims (3)

(57) [Claims] A first conversion means for converting external serial data into parallel data;
First and second storage means for temporarily storing said parallel data from the beauty second converting means, said first and second variable
Counts up every time conversion is performed by the conversion means
First and second address counters, and the first and second address counters;
The first and the second based on the count value of the address counter of
Controlling the reading of the parallel data from the second storage means
First and second read control means for performing
Switching means for selecting and outputting one of the parallel data read from the first and second storage means under the control of the second read control means ;
When a failure of the serial data to one of the conversion means is detected, one of the first and second conversion means
Address indication means for indicating the previous address to the read control unit the fault occurs corresponding to the other, the first based on the address indicated by the address indication means
And switching instruction means for instructing the switching means to select parallel data read from the storage means corresponding to the other of the second conversion means.
Data switching device . 2. The method according to claim 1, wherein the address designating unit is configured to perform the first and second operations when at least one of detection of data loss in the serial data and failure information from outside is notified.
Failure occurs based on the count value of the second address counter
Including first and second generation means for generating the previous address
The faults generated by the first and second generating means.
The address before the occurrence is stored in the first and second read control means.
2. The method according to claim 1, wherein the step is instructed.
A data switching device as described in the above. 3. The first and second address counters
2. The apparatus according to claim 1, further comprising a determination unit configured to determine an input state of the serial data to the first and second storage units based on the count value and detect a data loss in the serial data. Data switching equipment described in 2
Place .