JPH039634A - Priority transmission system in remote supervisory and controlling equipment - Google Patents

Abstract

PURPOSE:To prevent unrequired data from being transmitted by setting a receiving state when priority is delivered, and cancelling transmission data when data desired to transmit first is not required to transmit based on the content of reception data. CONSTITUTION:A local side control part 44 resets the data in a buffer 35 in the case of receiving the data from another station at a state where the data to be transferred exists in the buffer 35, and performs transmission when no data is received from another station and a signal whose transmission right is delivered is received and also, when the possibility of simultaneous outgoing does not exist, transmission is executed to another station, and performs the transmission successively if the data to be transmitted next has the one of priority transmission. And the transmission is interrupted by resetting the buffer 35 when the reception data exists even when the data exists in the buffer 35, and also, the next data registration from a host side is awaited, and the preservation and the change of the data in a register 32 can be performed.

Description

[Detailed description of the invention]

A. Field of Industrial Application The present invention relates to a remote monitoring and control device in which a master station and a large number of slave stations are connected via a loop line, and transmit and receive data using a transmission right cyclic method, and in particular, transmit data multiple times during priority transmission multiplexing. Regarding a method for securing rights and a method for preventing transmission of unnecessary data. B1 Overview of the Invention The present invention is a remote monitoring and control device that transmits transmission data by receiving a transmission right transfer signal, continues to secure the transmission right during priority transmission multiplexing, and transmits data multiple times in succession. When data is registered and data is transmitted, priority is transferred when the reception of data from another station is started first or when the other station is transmitting and the own station is transmitting simultaneously, and the receiving state is entered. Depending on the content, data management can be performed in such a way that the data to be transmitted can be reliably canceled if the data that was previously intended to be transmitted no longer needs to be transmitted. C1 Conventional technology An example of a line configuration of a remote monitoring and control system in which a master station and a large number of slave stations are connected via a loop line is shown in FIG. 7 as a system with a floating group configuration. (A) of the same figure shows a normal state of deafness on the line. 3
There are eight slave stations 21-2.8 for each master station 11-13. is 3
one master station 11-l for each loop line 31-33,
Belongs to and is combined with. Loop line 3. ~3. The transmitted and received data is circulated in one direction (indicated by the arrow), and the slave stations 23,
2. is operated in the terminal mode belonging to both loop lines, and the slave stations 2. ．． 2. ．． 2. ．． 25.
l. 28 is operated in relay mode. In such a configuration, each loop line 3. By changing the affiliation of the slave stations to ~33, the communication function for all slave stations is restored. FIG. 3(B) shows the line configuration state after these restorations, and in FIG. 3(B), slave station 2. The recovery line configuration is shown when it is determined that there is an abnormality in the line between 2 and 27, in which slave station 2 belongs to the master station via loop line 3, and slave station 2. and 23 are loop lines 3. Belongs to the master station L. Here, the communication method between the master station and the slave stations uses the transmission right circulation method, and normally one fleet signal is circulated on the loop line, and the master station or slave station with transmission data is sent to the fleet. - When a free token signal is received, the free token signal is switched to a busy token signal, and the transmission data following the busy token signal is sent, and the transmission of other master stations or slave stations is locked by the circulation of the busy token signal. . Then, when a reception confirmation for data transmission is obtained from the destination station, the transmitting station circulates free tokens on the line and yields the transmission right to another station. The configuration of the master station and slave station in the above system is shown in FIG. 8 as a configuration related to transmitted and received data. A master station 1 is connected to a slave station 2 via a loop line 3. At the master station 1, control human power from an operator etc. is temporarily stored in a control human power storage section 5 via a control input coupling section 4, and is sorted based on priority etc. by a transmission data sorting section 6.
A transmission signal is created by the above, and sent from the line coupling section 8 to the loop line 3. Display input from the slave station is taken in from the line coupling section 8 to the receiving section 9, decoded by the received data decoding section 10, and displayed on a display or the like by the display output section II. In the slave station 2, the received input from the loop line 3 is connected to both the A and B sides of the loop line by the line coupling section 21 (see Fig. 7).
are taken into the receiving sections 22A and 22B, respectively, and the receiving section 22
One of the reception inputs A and 22B is selected by the selection section 23 and decoded by the reception data decoding section 24, and a control output is obtained from the output coupling section 25. In addition, the status signal to be monitored is transmitted to the human power coupling unit 2.
6, the change detection section 27 detects the state change, the startup storage section 28 stores the presence of a state change, the transmission data selection section 29 selects based on the priority, etc., and the selection section 23 selects the transmission section 30A or 30B, a transmission signal is created and sent out from the line coupling section 21. Here, if there is multiple important data in the data that the master station or slave station is trying to transmit, priority is given to continuously transmitting it multiple times up to a predetermined number of times (for example, 4 times) as priority data while continuing to secure the transmission right. Transmission processing is performed. In this priority transmission, priority data is registered in the transmission data memory of the transmitting unit (for example, 3OA in Fig. 8), the transmitting unit transmits this data for the first time, and after this transmission is completed, another prioritized data is registered. If there is, the data is registered a second time in the memory, and this registration causes the data to be transmitted a second time. Control is repeated up to a predetermined number of times. D1 Problems to be Solved by the Invention In a system that uses the conventional transmission right circulation method and has a priority transmission function, it is required to inject fleet tokens so that the transmission right can be promptly handed over to another station when transmission is completed. However, when priority transmission is performed, free tokens are not injected and transmission rights are secured and multiple (for example, four) consecutive transmissions are performed, resulting in a delay in the transfer of transmission rights. To explain this in detail, the transmitting station registers the data to be transmitted next after the transmission is completed, determines whether that data is priority data, and injects fleet tokens accordingly or continues data transmission. Control what you do and how your fleet
Kun's injection will be delayed. At this time, when multiple stations are waiting for transmission, the interval between data transmissions of the multiple stations becomes long, and it takes a long time to complete the transmission of all data. In order to solve this problem, a processing method may be considered in which the transmitter can register the next transmission data in the transmission data memory in advance before the end of the transmission. This processing method has a block diagram configuration shown in FIG. This figure shows a part corresponding to the transmitter 30A or 30B of the slave station 2 in FIG. At the same time as registering the flag 33, this flag 33
The local control unit 34 sets the register 32 by setting
The registered data is transferred to the transmission buffer 35, and thereafter, when the control section 34 determines that the free token FT has been received, the data in the transmission buffer 35 is given to the parallel-to-serial conversion section 36 to convert it into serial data. , this serial data is sent to the loop line side through the modulator 37. With such a configuration, the transmission process takes the form shown in FIG. 10. In non-priority transmission (normal transmission), the host side writes data to the register 32 at the start of transmission and sets the write flag 33. Write flag 33 on local side
Knowing that is set, register 3 at the start of transmission
Transfer the contents of 2 to the buffer 35 and write the write flag 33.
Reset. The host side learns that the write flag 33 has been reset, registers data B to be transmitted next (non-priority transmission data in this example) in the register 32, and sets the write flag 33. When the local side receives the free token FT, it converts it in the converter 36 and modulates it in the modulator 3.
7 modulation transmission is performed. When the transmission of data A is completed, data B to be transmitted next is transferred to the buffer 35, and its contents are checked to determine whether or not there is priority transmission, and if it is non-priority, a free token FT is sent to grant the transmission right. Transfer to another station and transmit data B at the next free token FT reception. When the transmission of data B is completed, the data to be transmitted next is not registered in the illustration, so
Transfers the transmission right to another station by transmitting a free token. Next, in priority transmission, after transmitting data C, if priority transmission is determined by determining the presence or absence of priority transmission of the next transmission data D, data D is transmitted without transmitting a free token FT. Next, if the data E is priority transmission data, the data E is continuously transmitted. In this way, by temporarily transferring the registration data from the host side to the register 32 to the buffer 35, the next data from the host side can be transferred to the register 32 before the transmission of the data is finished.
Compared to the conventional system where the next data is registered in the register 32 from the host side at the end of transmission, it is determined whether or not priority transmission is to be performed, and whether or not Fleet Tokens can be injected. injection will no longer be delayed. However, the above processing method has the problem of unnecessary data transmission. This will be explained below. In Figure 1O, the local side transfers data A to buffer 3.
5, the transmission of the data A may become unnecessary or impossible. This state is (1) Free Token FT
When a station receives data from another station and becomes a receiving station before transmitting data A, and the content of the received data is such that data A should not be transmitted. (2) After receiving the Free Token FT and starting the transmission of data A, if there is a transmission from another station and the priority is transferred in so-called simultaneous transmission, that is, if the station loses the simultaneous transmission and becomes the receiving station, Similarly to (+), when the content of the received data is such that data A should not be transmitted. (3) When the transmission destination partner station changes line configuration due to the above-mentioned line failure and is coupled to another loop line, and the transmission destination station disappears from the line to which the transmitting station belongs. In these states, the host side resets the data A registered in the register 32 of the transmitting station, but the local side also needs to erase the data A existing in the buffer 35, etc., and without this reset, the above (1) and ( In item 2), data that is no longer necessary to be transmitted due to received data is transmitted. Furthermore, the above-mentioned item (3) results in a communication to which there is no recipient, which is not desirable. Furthermore, regarding the above-mentioned deletion of data A, it is difficult to reset data A that has been imported locally from the host side. Further, in a reset after data B, which follows data 8, is registered in the register 32, it becomes difficult for the host side to determine whether or not data A exists. Means and operation for solving the E1 problem The present invention has been made in view of the above-mentioned problems, and includes a register in which transmission data is registered, and a transmitter to which the data in this register is transferred and outputs the transmission data. A buffer, a write flag that instructs data registration and reading in the register, a host-side control unit that can control data registration in the register and on/off of the flag, and a host-side control unit that transfers the data in the register to the transmission buffer and writes this data. and a local side control unit that can transmit data, and when the local side control unit receives data from another station when there is data to be transferred to the transmission buffer, it resets the data in the buffer, and when there is no data received from the other station and the data is transmitted, the local side control unit resets the data in the buffer. The transmission method is to transmit when the signal to which the rights have been transferred is received and there is no loss of simultaneous transmission with other stations, and to continue transmitting if the next data to be transmitted is priority transmission,
Even if there is data in the transmit buffer, the buffer is reset when there is received data to stop the transmission and wait for the next data registration from the host side, making it possible to save and change the data in the register. . The present invention also provides a register in which transmission data is registered;
A write flag that instructs data registration and successive output in this register, a priority transmission wait flag that instructs priority transmission of the next data to be registered in the register, and data registration in the register and on/off of the flag can be controlled. The host-side control unit includes a host-side control unit and a local-side control unit capable of transmitting the data in the register, and the host-side control unit sets the priority transmission waiting flag depending on whether or not the next data to be registered in the register is for priority transmission. On/Off setting, and the local control unit transmits when the write flag is in the on state, when there is no data reception from another station and the transmission right is handed over, and when there is no loss in simultaneous transmission with other stations. When the transmission is completed, the write flag is turned off. Then, if the priority transmission waiting flag is off, a free token is injected and the transmission right is transferred to another station, and if it is on, the next data to be transmitted is continued. This is a transmission method in which both flags are turned on and off by the control units on the host side and the local side, which enables the process of canceling transmission and saving and changing data in registers. The present invention also provides a pair of registers in which transmission data is registered, a pair of write flags that respectively instruct data registration and readout of the registers, and a demultiplexer that switches and registers the transmission data in the pair of registers. a multiplexer that switches and retrieves registered data in the pair of registers; and a host-side control unit that can alternately register transmission data in the pair of registers and control on/off the corresponding pair of write flags under the control of the demultiplexer. , a local-side control unit that can alternately retrieve and transmit the data in the pair of registers under the control of the multiplexer, and the local-side control unit reads the data in the pair of registers in accordance with the ON state of the write flag. Take out data alternately, transmit when no data is received from another station, the signal to which the right to transmit has been transferred is received, and there is no loss of simultaneous transmission with another station, and write the transmitted register when transmission is completed. Turn off the flag, then switch the paired registers, and if the next transmission data is priority transmission, transmit the next data while securing the transmission right,
If it is not a priority transmission, the transmission method injects free tokens and transfers the transmission right to another station, and by alternately registering and transmitting data to a pair of registers, it is possible to save and manage data when transmission is stopped. do. F. Embodiment FIG. 1 is a transmission processing block diagram showing an embodiment of the present invention, and the same parts as those shown in FIGS. 8 and 9 are designated by the same reference numerals. In FIG. 1, received data from a loop line passes through a demodulator 41 and a serial-to-parallel converter 42 and is registered in a reception completion register 43, and from the data in this register 43, a control unit 31 determines whether the received data has been completely captured. Then, the data is transferred to the received data decoding section 24. On the other hand, for data transmission, the local side control section 44 transmits the data in the transmission buffer 35 to the converter 36 via the modulator 37 to the loop line. When the transmission of 1 is completed, it is registered in the transmission completion register 45, and by this registration, the host side control unit 3

[determines whether the transmission is complete. A detection unit 46 for detecting the presence or absence of priority transmission is provided on the local side, and detects the presence or absence of priority transmission from the data output of the transmission buffer 35, and the control unit 44 takes in this detection result. FIG. 2 shows a flowchart at the time of transmitting station transition in such a configuration. Signal paths corresponding to steps #1 to #31 in the figure are indicated by the same reference numerals in 111ffl. On the host side, the control unit 31 determines the presence or absence of transmission data from the data selection operation of the transmission data selection unit 29 in step #l.
), when there is data to be sent, the flag 33 is turned off (data in the register 32 has been transferred to the buffer 35), and the data of the encounter section 29 is registered in the register 32 and the flag 33 is turned on. (Step #3). Next, processing on the local side will be explained. The control unit 44 determines the presence or absence of data in the transmission buffer 35 (step #1);
If there is no data, it is difficult to determine whether the flag 33 is on or not (step #2), and when the flag 33 is on, the converter 3
6 during idle (step #3), the data in the register 32 is transferred to the transmission buffer 35, and then the flag 33 is turned off (step #4). Here, when it is determined in step #l that there is data in the buffer 32, the control unit 44 determines from the state of the converter 42 whether or not it is receiving data (step #11), and if it is receiving data, it resets the transmitting buffer 35. Step #12), perform a receiving operation. On the other hand, when not receiving, directly step #2
Go to 1. Therefore, when reception from another station is started while there is data to be transmitted in the transmission buffer 35, the data in the transmission buffer 35 is reset. Next, in step #21, when a free token is received, the control unit 44 starts transmission to start the conversion operation of the converter 36 (step #22), and in this start of transmission, there is no communication with the transmission from another station. The control unit 44 determines whether or not there is a simultaneous transmission loss from the received signal of the converter 42 (Step #23), and if there is no simultaneous transmission loss, the transmission is continued and the transmission is completed (Step #24). The reset and transmission completion signals are registered in the register 45, and the host side is notified and the transmitting station is canceled (step #25). With this one transmission, the control unit 44 determines whether or not the four priority transmissions have been transmitted using an internal counter (step #26); if the transmission has not been completed, the control unit 44 determines whether the flag 33 is turned on (step #27). If it is on, the data in the register 32 is transferred to the buffer 35 and the flag 33 is turned off (step #28), and the presence or absence of priority transmission is determined from the signal of the detection unit 46 (step #29). Set the priority transmission transmission count counter to +IL, (Step #30
), the transmission continues in step #22. Also, at the end of the 4th transmission in priority transmission, the transmission count counter is set to zero,
Transfer transmission rights to other stations by injecting free tokens (step #
31). Furthermore, if the destination station disappears, the host side detects this and transmits a transmission reset signal to the local unit via 47, and the local unit resets the transmission buffer 35. As described above, in this embodiment, when transmitting the data fetched into the transmission buffer 35, the transmission buffer 35 is reset if data is being received before receiving a fleet token, and when data is being transmitted after receiving a fleet token, the transmission buffer 35 is reset. The transmission buffer 35 is also reset when simultaneous transmission is lost. The cancellation of the transmitted data at the time of data reception is performed in the local transmission buffer 35 as described above, eliminating the need for cancellation processing on the host side and preventing the transmission of unnecessary data. register 3
It is also possible for the host side to determine whether or not to cancel the data remaining in 2. Further, when the destination station disappears, unnecessary communications are no longer made. FIG. 3 is a block diagram showing another embodiment of the present invention,
The flowchart is shown in FIG. The same parts as in FIG. 1 or 2 are indicated by the same reference numerals, and detailed explanation thereof will be omitted. In FIG. 3, in a configuration in which the local side does not have a transmission buffer, a priority transmission waiting flag 51 is provided between the local side and the host, and this flag 51 contains data waiting to be transmitted next from the host side control unit 52. The local control unit 53 reads from the state of the flag 51 whether there is priority transmission waiting or not, and whether or not the transmission right should be secured after the completion of transmission. The operation will be described below with reference to FIG. 4, which shows a transmitting station migration flowchart in the above-described configuration. On the host side, with the flag 33 on, it is determined whether the next data to be transmitted is priority transmission (step #4), and depending on this determination, the priority transmission waiting flag 51 is turned on or off (steps #5 and #6). ). On the local side, the presence or absence of transmission data is determined from the state of the flag 33 (step #2), and if data is registered, transmission is performed after waiting for free token reception (step L2+). In this transmission, as in the case of FIG. 2, priority transmission processing begins after simultaneous transmission failure determination processing. For this priority processing, following step #26, priority transmission waiting is determined from the ON of priority transmission waiting flag 51.Step #29A), flag 3
3 is turned off (step #28A), the next data registration from the host side (in priority transmission) is determined from the flag 33 and waits (step #27), and after registration, the priority transmission count counter is incremented by 1. (Step #30). Further, when the priority transmission limit number of times is reached or flag 5 is turned off, that is, there is no priority transmission waiting, the flag 33 is turned off (step #28), and the priority transmission counter is set to zero and fleet Nikon injection is started (step #31). Therefore, in this embodiment, a transmission buffer is not prepared on the local side, and after registering data from the host side to the register 32,
Next, set the flag for data priority transmission or not at the time of registration,
If this flag is off, free tokens are injected immediately upon completion of one transmission, and when the flag is on, upon completion of one transmission, new data is waited for registration from the host side before being transmitted. Thereby, the same effects as in the first embodiment can be obtained. FIG. 5 shows another embodiment of the present invention, and FIG. 6 shows a transmitting station migration flowchart thereof. The difference between FIG. 5 and FIG. 1 is that no transmission buffer is provided, two registers 32A and 32B are provided instead of register 32, and a flag 33 is provided.
Instead, flags 33A and 33B are provided, and the host side registers data and switches the flags on and off through a demultiplexer 55, and on the local side, the data in one of the registers 32A and 32B is switched through a multiplexer 56. Extraction and transmission are performed, and flags 33A and 33B are turned off and read. These controls are executed by the host control unit 57 and the local control unit 58. In FIG. 6, which shows a flowchart of such processing, the host side registers transmission data alternately in registers 32A and 32B and turns on the corresponding flags 33A and 33B (steps #2A, #2B, #3A, #3B). ). On the local side, the flag 33A is turned on and off (step #2A) and the flag 33B is turned on and off (step #2B).
, #2B') to alternately transmit the registered data of registers 32A and 32B (steps #3, #4, and #5).
. The transmission is started by free token reception (step #21), and each time one transmission is completed, the flag of the side that will be the next transmission data side is read (step #27), and if the next transmission is priority transmission, the flag is read four times. It continues to secure the transmission right after reaching the limit, and if it is not a priority transmission, it injects free tokens and transfers the transmission right to another station. The write flag 33 is also turned off for the flag on the side where transmission has ended (steps #29A and 929B).
. With this process, there is no need to set up a transmission buffer.
To ensure and easily cancel processing of data that no longer needs to be sent, and to eliminate unnecessary communications. Effects of the G3 Invention As described above, according to the present invention, since it is possible to stop transmission and change data when transmitting data, it is possible to reliably prevent the transmission of unnecessary data and perform reliable monitoring control. Transfer of transmission rights after completion is also possible without delay.
Moreover, the processing at the transmitting station will not become difficult.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention;
3 is a block diagram showing a second embodiment of the present invention, FIG. 4 is a flowchart of FIG. 3, and FIG. 5 is a flowchart of a third embodiment of the present invention. 6 is a flowchart in FIG. 5, FIG. 7(A) is a circuit configuration diagram of the fluid solution method,
FIG. 7(B) is a diagram of a configuration modified due to a line abnormality, FIG. 8 is a block diagram of a master station and a slave station, FIG. 9 is a schematic diagram of a conventional transmission process, and FIG. 10 is a diagram of a conventional process. 31... Host side control unit, 32... Transmission start waiting register, 33... Write flag, 35... Transmission buffer, 43... Reception completion register, 44... Local side control unit, 45 ...Transmission completion register, 46...
Priority transmission detection unit, 47... Transmission reset, 51...
Priority transmission waiting flag, 52... host side control unit, 53.
...Local side control unit, 32A, 32B... Transmission start wait register, 33A, 33B... Write flag, 5
5... Demultiplexer, 56... Multiplexer, 57... Host side control unit, 58... Local side control unit. Figure 10 Figure 10 Conventional processing

Claims (3)

[Claims] (1) A master station and many slave stations are connected by a loop line, and data is sent and received using the transmission right circulation method, and important data is transmitted by a remote monitoring and control device that secures the transmission right and performs priority transmission. A register in which data is registered, a transmission buffer to which the data in this register is transferred and outputs transmission data, a write flag that instructs data registration and reading of the register, and a register that registers data in the register and turns on/off the flag. A host side control unit that can control off,
and a local side control unit that can transfer data in the register to a transmission buffer and transmit this data, and when the local side control unit receives data from another station when there is data to be transferred to the transmission buffer, the data in the buffer is transferred. Reset the , transmit when there is no data received from another station and a signal to which the transmission right has been transferred, and when there is no loss of simultaneous transmission with other stations, and if the next transmission data is priority transmission, the transmission right is transferred. A priority transmission method for remote monitoring and control equipment, which is characterized by transmitting while ensuring the following. (2) In a remote monitoring and control device that connects a master station and a number of slave stations via a loop line, transmits and receives data using the transmission right circulation method, and performs priority transmission by transmitting important data while securing the transmission right. A register in which data is registered, a write flag that instructs data registration and reading of this register, a priority transmission wait flag that instructs priority transmission of the next data to be registered in the register, and data registration and flag in the register. a host-side control unit that can control on/off of the register, and a local-side control unit that can transmit the data in the register, and the host-side control unit can control whether the next registered data to the register is priority transmission or not. sets the priority transmission wait flag on/off, and the local side control unit receives a signal indicating that the transmission right has been handed over due to no data reception from another station while the write flag is on, and transmits simultaneously with the other station. A priority transmission method for a remote monitoring and control device, characterized in that transmission is performed when there is no loss, and if the priority transmission waiting flag indicates priority transmission of the next transmission data, transmission is performed while securing the transmission right. . (3) In a remote monitoring and control device that connects a master station and a number of slave stations via a loop line, transmits and receives data using the transmission right circulation method, and performs priority transmission by transmitting important data while securing the transmission right. A pair of registers in which data is registered, a pair of write flags that respectively instruct data registration and readout of the registers, a demultiplexer that switches and registers transmission data to the pair of registers, and registration data of the pair of registers. a host-side control unit that can alternately register transmission data in the pair of registers under the control of the demultiplexer and control on/off the corresponding pair of write flags; a local-side control unit that can alternately take out and transmit data in the pair of registers, and the local-side control unit alternately takes out the data in the pair of registers as transmission data according to the ON state of the write flag, and Transmit when a signal is received with no data received from a station and the transmission right has been transferred, and there is no loss of simultaneous transmission with other stations, and if the next transmission data is priority transmission, the transmission right is secured. A priority transmission method for remote monitoring and control equipment that performs transmission.