JPS61230447A - Test system of loop network - Google Patents

Abstract

PURPOSE:To eliminate the need for new transmission of a test signal and to test separately the reception only by receiving a polling signal sent from a trigger station at all times only at the test. CONSTITUTION:When each node station (NS) conducts the test of the own reception in a loop network, an NS control section 6 in each NS writes a destination address of a polling signal to an address filter 8 via an output 6-2 so as to give a command of the reception of the polling signal. When the address filter 8 receives the command, every time a polling signal reaches, it is informed to a reception control section 9. The NS control section 6 conducts the test of the own reception, that is, address coincidence detection functionof the address filter 8, control operation of the reception control section 9, an end delimiter ED detection function of an ED detection section 2 and further, the operation of a reception memory by checking whether or not the said fixed pattern given to the INFO part of the polling signal is written normally in a reception control memory 10.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a system in which a node station connected to a loop network tests its own operation.

・(Prior art and its problems) In addition to the integration of voice communication and data communication, the 1988 Institute of Electronics and Communication Engineers Exchange Research, for example, There is a loop network described in ``A Study of High-Speed Synchronous Packet Loops'' in Conference Material 5E83-107.

This loop network constitutes a network as shown in FIG. In the figure, trigger stage TS20 transmits a polling signal onto transmission line 24 to perform polling control on node stations N521, N522, and N523. Further, the node stations N521, N522, and N523 transmit and receive packets via the transmission path 24 in accordance with the polling control. These stations are connected in a loop through a transmission line 24 as shown in the figure. (In this specification, the trigger station is abbreviated as TS, and the node station is abbreviated as NS, and TS and NS are collectively referred to as a stage.) In this loop network, as shown in FIG. Then, the TS 20 transmits a polling signal (pl or p2), and each NS monitors the polling signal passing on the transmission path 24, prepares to transmit a packet, acquires the transmission right, and then transmits the packet. For example, in the example shown in Figure 1, N521 receives the polling signal p1 transmitted by TS20, acquires the transmission right after passing the polling signal p1, and transmits the bucket)al. After receiving the polling signal p1, N522 acquires the transmission right after passing the bucket)al and transmits the packet b1. Similarly, N523 also transmits packet C1.

When the polling signal p1 transmitted by itself returns after going around the transmission path 24, the TS 20 transmits the polling signal p1.
1 is removed from the transmission path 24. In the figure, the signals removed at each stage are indicated by crossed marks. ), further NS
After passing the packets a1, bl, and C1 transmitted by 21, N522, and N523, it acquires the transmission right,
Send next polling signal p2 and bucket to N521)
Start sending a2. In addition, when each NS also returns after going around the packet transmission path 24 that it sent, the transmission path 2
Remove from 4.

The signal transmitted once in this way is removed at the transmission source stage 1 after going around the transmission path 24.

FIG. 5 is a diagram showing the frame structure of a polling signal transmitted by the TS 20 and a signal transmitted by each NS, and both signals have a common frame structure. In FIG. 5, SD is a start delimiter that signals the start of a signal,
CF is a polling signal sent by TS20 or NS
DA is the destination address of the signal, SA is the source address of the signal, INFO is the message part, and ED is the end delimiter that indicates the end of the signal. be.

Each NS decodes the CF part of the signal passing through the transmission path 24 to detect a polling signal, and the DA part
It is determined whether the address matches the address of S, and if they match, the same signal is received in the reception memory in the NS.

In the loop network NS described above, the signal passing through the transmission line 24 is monitored, the specified destination address DAt is identified, the signal is stored in the reception memory, and the stored signal is read out from the reception memory without error. It is necessary to test the reception operation to see if it is possible to do so. As an alternative method, a method is considered in which a signal addressed to its own NS is sent and the signal is received after going around the transmission path 24.

As can be seen, in this method, the receiving operation cannot be tested until the normal state of the transmitting operation is confirmed. Therefore, a more complicated test method must be performed to determine which parts of the NS are normal and which parts are not.

(Object of the Invention) An object of the present invention is to provide a test method in which a node station connected to a loop network tests only its own reception operation by separating it from other operations, thereby easily testing the reception operation. It is in.

(Structure of the Invention) According to the present invention, one trigger station run and a plurality of node stations are connected in a loop through a transmission path, and the trigger station transmits a polling signal to the node station to control transmission. The trigger stage 4 gives a certain bit pattern to the message part of the polling signal and transmits it to the transmission path, and when the node station performs its own operation test, the trigger stage A loop network testing method is obtained, characterized in that an operation test is performed by receiving a signal and detecting the certain bit pattern.

(Detailed Description of Configuration) FIG. 1 shows the internal configuration of each NS based on the present invention. The signal on the transmission line 24 is sent to switch 1 when the NS is not transmitting.
an ED detection unit 2 that is bypassed to the adjacent stage via the signal and detects the end delimiter ED of the signal;
An idle state detection section 3 that detects the idle state of the transmission line 24, a polling signal detection section 7 that detects the polling signal transmitted by the TS 20, an address filter that detects the destination address DA part of the signal and detects the self addressed to the own NS. Part 8
is input.

When the NS performs transmission, the NS control unit 6 stores the signal to be transmitted in the transmission register 5 and notifies the occurrence of a transmission request via the output 6-1 of the same unit, and the access control unit 4 that receives this
After the polling signal detection unit 7 receives a notification of detection of a polling signal passing through the transmission path 24, it enters a transmission standby state.

Furthermore, when the idle state detection section 3 notifies the access control section 4 that it has detected the idle state of the transmission path 24 immediately after receiving the ED detection notification from the KD detection section 2, the access control section 4 acquires the transmission right and switches the 1 to the transmission register 5 side and start transmission.

Further, in order to receive a signal addressed to the own NS, the NS control unit 6 in each NS detects a signal in which its own address is specified in the destination address DA section of the signal via the output 6-2 of the same part. The address filter 8 then notifies the reception control unit 9 every time it detects a signal addressed to its own NS from among the signals on the transmission line 24. Reception control section 9
When it receives the detection notification of the signal addressed to its own NS from the address filter 8, it stores the signal in the reception memory IO, and when it learns that the ED detection unit 3 has detected the end delimiter ED of the signal, it stores the signal in the reception memory 10. Finish storing the signal.

FIG. 2 shows the internal configuration of the TS20. The polling control section 11 inside the TS 20 instructs the access control section 4' to transmit a polling signal and starts polling control. Upon receiving this instruction, the access control section 4' connects the switch 1 to the transmission register 5 side, and transmits the polling signal stored in the register to the transmission line 24.

Once the TS 20 transmits the polling signal in this way, the idle state detector 3 detects the idle state of the transmission line 24 immediately after receiving the ED detection notification from the ED detector 2, as explained in FIG. Each time the access control unit 4' acquires the transmission right, it repeatedly transmits the polling signal in the transmission register 5.

(Example) Next, an example of the present invention will be described using FIG. 1 and FIG. 2. In the TS 20 shown in FIG. 2, the polling control unit 11 stores the polling signal in the transmission register 5, but at this time, the polling signal's destination address
An address that is not permitted to be used by any NS, for example, the address of the TS 20 itself, is specified in the message part INFO, and a fixed bit pattern predetermined within the loop network is stored in the message part INFO.

Therefore, the polling signal detection unit 7 in each NS
Although it detects a polling signal passing above, it does not receive the same signal in its own reception memory 10.

On the other hand, in each NS shown in FIG.
An instruction is given to part A to detect a signal specifying the address of its own NS.

When each NS tests its own reception operation in such a loop network, the NS control unit 6 in each NS writes the destination address of the polling signal mentioned above to the address filter 8 via the output 6-2. Instructs to receive/perform polling signals.

When the address filter 8 receives this instruction, it notifies the reception control unit 9 every time a polling signal arrives. Therefore, from now on, this NS receives a polling signal every time it arrives and stores it in the reception memory 10. The NS control unit 6 checks whether the above-mentioned fixed pattern given to the INFO section of the polling signal is correctly written in the reception control memory 10 to perform its own reception operation, that is, address match detection of the address filter 8. It is possible to test the function, control operation of the reception control section 9, end-of-day detection function of the ED detection section 2, and operation of the reception memory 10.

(Effects of the Invention) As described above, each NS receives the polling signal that the TS 20 always transmits only during the test, so there is no need to newly transmit the test signal.
It is possible to test only the reception operation separately, and the reception operation can be tested easily.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration inside the node stage NS,
FIG. 2 is a diagram showing the configuration inside the trigger station TS, FIG. 3 is a diagram showing the configuration of the loop network, and FIG.
The figure shows a signal flow, and FIG. 5 shows a signal frame structure. In the figure, 1 is a switch, 2 is an ED detection section, 3 is an idle state detection section, 4, 4' is the access control section, 5 is the transmission register, and 6 is the NS control section.
-1.6-2 is the output of the same group, 7 is the polling signal detection section, 8 is the address filter, 9 is the reception control section, 10 is the reception memory, 11 is the polling control section, 20 is the trigger station TS, 21, 22 .23 indicates the node stage transmission line NS, 24a. Kyou 1 TS:)-Riga Station NS: Node Stage Koshi-tei 4 Figure Time

Claims (1)

[Claims] A test method for a loop network in which one trigger station and a plurality of node stations are connected in a loop through a transmission path, and the trigger station transmits a polling signal to the node station to control transmission, the trigger station The station gives a certain bit pattern to the message part of the polling signal and transmits it to the transmission path, and when the node station performs its own operation test, the station receives the polling signal and detects the certain bit pattern. A loop network test method characterized by performing an operation test.