JPS5930337A - Loop data transmitter - Google Patents

Abstract

PURPOSE:To keep the communication efficiency at a high degree, by rewriting a time data set initially so as to set optionally the time of retransmission operating interval and limit of response. CONSTITUTION:Each section is diagnosed with a program of a memory 30, time data T1, T2, T11-T14 are stored in addresses A1, A2, A11-A14 to complete the initial setting (hereinafter, time data is written as An). When a frame comes to a data processor of the own station, a processor 29 interrupted from a transmission/reception controlling section 23 reads out the A1 from the memory 30, ses it in a timer 25, transfers the received frame to a transmission/reception controlling section 22 for attaining serial-parallel conversion and transmits it to the data processor of the own station after modulation. In case of the receiving of REJ FRAME, the processor 29 sets the A2 to the timer 25, and the time is out after the lapse of the time A2. When the number of time-out reaches a prescribed number, a failure of disable transmission is informed to the transmitting station. In case of ACP FRAME reception, the timer 25 is stopped and the frame transfer is completed. The same processing is attained in case of no response.

Description

[Detailed description of the invention] The present invention relates to a loop data transmission device.

As shown in FIG. 1, the loop data transmission system has loop data transmission devices 2 to 7 for transmitting and receiving data connected in a loop through a line 1, and data processing devices 8 to 13 connected via each loop data transmission device. ing. Data is transmitted between each data processing device using a frame having the structure shown in FIG. A frame has a flag sequence F that indicates the beginning and end of the frame, a data destination address DA that indicates the data receiving station, a data source address SA that indicates the data originating station, and a control code CTL.

It consists of an information field INF for carrying transmission data, and an error check word FC8 for carrying out an error check for frame data.

The communication state between the loop data transmission devices is controlled, and the loop data transmission device that has acquired the data transmission t'ft is sending out data in the form of a frame.

In FIG. 1, data processing device 8 to data processing device 1
The transfer of data will be explained using an example of transferring data to 1. The data processing device 8 puts the data to be transferred in a frame and sends it to the loop data transmission device 2. The loop data transmission device 2 checks the destination address DAi of the frame, confirms that it is not addressed to its own station, and sends the frame to the line 1. The loop data transmission devices 3 and 4 check the destination address DA of this frame, confirm that it is not addressed to their own station, and relay the entire frame to the line 1. The loop data transmission device 5 checks the destination address DAffi of this frame, confirms that it is addressed to the data processing device 11, takes the frame, and sends an ACCEPT signal f7 v -A to notify that the frame has been received.
(ACP FRAME) is sent to the loop data transmission device 2.

Further, the loop data transmission device R5 sends the received frame to the data processing device 11. Loop data transmission device 2
is this ACPFRAMEffi addressed to the local data processing device.
ACP FRAME i which receives and reports that the frame has been received by the destination loop data transmission device 5.
Ends the sending frame transfer operation.

In the above case, the frame is normally received by the loop data transmission device 5, which is the other station, but if the frame has an error due to transmission path noise or the like, or if the loop data transmission device 5 has a failure, The frame is not received and the AC
PF'RA, ME returned carp.

There are cases in which the reception buffer memory of the loop data transmission device 5 is full and the frame is temporarily unable to be received, and the loop data transmission device 5 is busy. In the latter case, when a frame arrives, a REJBCT signal (referred to as REJ FMME) is sent back from the loop data transmission device #L5, which is the relay station 5-1, to the loop data transmission device 2, which is the originating station. Notify that.

In such cases of no response or busy, the loop data transmission device 2 retransmits the frame after a certain period of time has elapsed to ensure communication reliability. In other words, the loop data transmission device 2 waits for a certain period of time T' after transmitting the frame.
ts″fr: If there is no response after elapsed time, the frame retransmission operation starts completely.Also, when the loop data transmission device 5 receives a response of REJFRAME because it is busy, the loop data transmission device i12 sends )l, EJ FRAME
After reception - After the reception amount T14 has elapsed, the frame retransmission operation is started. Furthermore, the data processing device [8 to data transmission device 2]
If the loop data transmission device 5 does not respond or the busy state is not released even after a certain period of time T, 1'i has passed after receiving the frame, the loop data transmission device 2 sends RFliJ Fit, AMg to the data processing device 8. It notifies that frame transfer is to be abandoned and ends the frame transfer operation.

As the number of loop data transmission devices constituting the loop data transmission system increases, in order to maintain the communication efficiency of the transmission system at all altitudes, the frame retransmission operation interval time T13 and T14 k The number of loop data transmission devices must be increased. Compared to those with a small amount, it is forced to be thick C.

In addition, in a specific case where the data processing device requests an immediate response, T11 # T13 is higher than in the normal case.
It is also necessary to reduce T14.

In the conventional device, the frame retransmission operation interval time T1! .

'I'ts and T14 are fixed, so TlK
.

A drawback is that Tla and T14k cannot be varied to maintain the communication efficiency of the transmission system at full altitude or to meet the specific requirements of the data processing equipment.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and to provide an entire loop data transmission device that can arbitrarily set the frame retransmission interval time.

The device of the present invention includes a storage means for storing all time data and a storage means for storing predetermined time data in a plurality of loop data transmission devices connected to a loop line for data transmission between a plurality of data processing devices. initial setting means for writing to a predetermined address of the storage means; rewriting means for rewriting all the time data stored in the storage means with time data supplied from the data processing device; and own station data. First time data or second time data stored in the storage means in response to relaying of an information frame from the processing device to the data processing device of another station or from the data processing device of the other station to the data processing device of the local station. is set, and third time data or fourth time data stored in the storage means is set in response to reception of an unreceivable frame from each of the destination devices, and the time specified by the set time data. a first time signal generating means for generating a first time signal when the first time signal has elapsed;
information frame retransmission means for retransmitting the information frame in response to the supply of the time limit signal; and stopping the operation of the first time limit signal generating means in response to the reception of the received optical frame from the destination device. and a first time signal generation stop means.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 3 is a block diagram of one embodiment of the present invention.

One embodiment of the present invention includes modulation/demodulation sections 21 and 24.degree. transmission/reception control sections 22 and 23. Timer 25, 26° 27 and 2
8. It is composed of a processor 29 and a memory 30. The modem unit 21 connects the external data processing device to the connection line 1.
02, and supplies the demodulated signal to the transmission/reception control section 22 via the connection line 104, and also modulates the signal supplied from the transmission/reception control section 22 via the connection 103t-. It is supplied to a data processing device via a connection line 101.

The modulation/demodulation unit 24 demodulates a received signal supplied from an adjacent loop data transmission device via a connection line 109 (loop line) and supplies the demodulated signal to the transmission/reception control unit 23 via all connection lines 107, and also performs transmission/reception control. Connecting wire 108 from section 23
It modulates the signal supplied via the 9- signal and supplies it to other adjacent loop data transmission devices via the connection line 110 (loop line).

The transmission/reception control section 22 converts the serial data supplied from the modulation/demodulation section 21 via the connection line 104 into parallel data, converts the parallel data supplied via the bus 111 or the connection line 105 into all serial data, and converts the serial data supplied via the connection line 104 to the connection line. 103 all through change i
A direct←→parallel conversion circuit that supplies the first part 21, a buffer memory that temporarily stores received data, and an ACP FRAME.
Or it has a receiving bar for REJ FR-AME. Further, when data is received via the connection line 104, the transmission/reception control unit 22 interrupts the processor 29 via the bus 111, and subsequent operations are performed from the processor 29 to the bus 111.
This is done by a signal supplied via the .

The transmission/reception control unit 23 converts the serial data supplied from the modulation/demodulation unit 24 via the connection line 107 into parallel data, converts the parallel data supplied via the bus 111 or all connection lines 106 into serial data, and converts the parallel data supplied via the bus 111 or all connection lines 106 into serial data. It has a direct←→10- parallel conversion circuit that supplies the data to the modulation/demodulation unit 24 via 108, a buffer memory that temporarily stores received data, a circuit that checks the destination DAi of the received frame, and a generation circuit and a detection circuit for ACP FRAME and REJ FRAM. . When data is detected via the connection line 107, the transmission/reception control unit 23 checks the DA, and if it is not the own station or data processing device light, it immediately resends the frame to the loop via the connection line 108'lt.
Buffer memory gold check when own station or own station data processing device light.

When the buffer is full, send all R, BJ FRAME, and when it is not full, store all frames in the buffer LAcpF
Send RAME. When a frame is received, an interrupt is given to the processor 27 via the bus 111, and subsequent operations are performed by signals supplied from the processor 29 via the bus 111.

The timer 25 manages the frame retransmission operation interval time when the loop data transmission device transmits the frame from the entire frame loop line to the data processing device connected to the local station. The time data stored at address Al or A2 is set in the timer 25 and activated, and when the set time has elapsed, the timer 25 issues an interrupt to the processor 29.

The timer 26 is started when the time data stored in the address Atl of the memory 30 is set by the processor 29 when the loop data transmission device needs to transmit a frame to the loop line, and then the set time has elapsed. Occasionally, the timer 26 issues an interrupt to the processors 29 & 2m. This is a timer for managing the response limit time that is used when the other station cannot receive the frame even after a certain period of time has elapsed since the need for frame transmission occurred.

The point is that when the timer 27 starts, the processor 29 sets the time data stored in the address A42 of the memory 30 and starts up, and then when the set time has elapsed, the timer 27
An interrupt is placed on the process S29.

The transmission right frame (only the station that has acquired this frame can send the frame to the loop line, and after sending the frame to the loop line, it will release the transmission right, that is, send the transmission right frame) for a certain period of time. This is used when the own station reissues all transmission rights frames when the transmission rights frame cannot be acquired even after a long period of time (this occurs when transmission rights frames are lost due to line failure, etc.).

The timer 28 manages the entire frame retransmission operation interval time to other loop data transmission devices, and the processor 29 sets the time data stored in the address All or A14 of the memory 30 in the timer 28, starts it, and then sets it. When the specified time period has elapsed, an interrupt is generated from the timer 28 to the processor 29.

The memory 30 stores a control program for controlling the loop data transmission device, a diagnostic program, and the various time data described above.

A processor 29 reads out a control program stored in the memory 30 via the bus 111 and controls each operation of the data transmission device 13--.

Table 1 shows the address of the memory 30 where each time data is stored, what each time is to be managed, and the timer name to which each time data is set.

$ lL FIG. 4 is a flow diagram of initial setting of the loop data transmission device.

When the loop data transmission device is fully powered on, each part of the hardware is diagnosed by the diagnostic program stored in the memory 30 (step 401).
The control program stored in υtime data'r
1. T2. T1□, T12. T13 and T14
are the addresses AI and Ai of the memory 30.

A11 e ”42 m A13 OJ:bi A14 K
are stored (steps 402, 403, 404), respectively.
and 405) Initial settings are completely completed. From now on address An
The time data stored in is written as (An) (n=natural number).

FIG. 5 is a flow diagram showing the operation when the loop data transmission device receives a frame from its own data processing device or another loop data transmission device.

When 7 frames are detected from the data processing device of the local station, they are demodulated by the modem unit 21 via the connection line 102 and sent to the connection line 10.
4, the serial data is converted into parallel data by the transmission/reception control unit 22 (step 501).

Storing the frame in the receive buffer (step 502).

After that, the destination address D&' of the frame is sent via the 6 mark.
I check (step 503), if the address is for the own station, the 70- figure is connected to FIG. 50
A flow diagram is connected to FIG. 7 via the 3ON branch and (described later).

When a frame is detected from another loop data transmission device, it is demodulated by the modulation/demodulation unit 24 via the connection line 109, and converted from serial data to parallel data by the transmission/reception control unit 23 via the connection line 107 (Step 1).

step 504), and checking the destination address DAi (step 504).

Step 505), if it is addressed to the own station or the data processing device of the own station, it is checked whether the receive buffer of the transmission/reception control unit 23 is full (Step 506), and if it is full, the entire frame is discarded.Step 509) A REJ FRAME is sent to the station (step 510).

If the receive buffer is not full, store the frame in the receive buffer (step 507), ACPFR
Step 508) to send the AME to the partner station.

After that, the destination address DAi of the frame is sent via the O mark.
Check (step 512), and if it is addressed to your own station, go to step 5.
A flow diagram is connected to FIG. 8 via the 12 Y branches and the black mark (described later). In the case of the local data processing device optical, 70- is connected in FIG. 6 via the N branch of step 512 and the symbol ■.

If the frame is not addressed to the local station or the data processing device of the local station (step 505), that is, if a frame that is not addressed to the local device is received from another loop data transmission device, the transmission/reception control unit immediately proceeds to step 511. 23 converts the parallel data into serial data, and supplies the frame 2 to the modulation/demodulation section 24 via the connection line 108, where it is modulated and sent to the loop line 11.
(Retransmitted into the loop via l.

The operations shown in the flowchart of FIG. 5 described above are from step 501 to
502 and steps 504 to 511 are performed by hardware in the transmission and reception control units 22 and 2317-, and the transmission and reception control units 2 and 2317- are respectively executed with a 0 or 0 mark.
2 or 23 to interrupt the processor 29 and start the processor 29.

FIG. 6 is a flow diagram showing the operation of the loop data transmission device when 7 frames are sent from another loop data transmission device to the local data processing device.

The process 29, which is interrupted by the transmission/reception control section 23, sets (7V1) km in the timer 25 from the memory 30 (step 601). The received frame is sent to the reception bar of the transmission/reception control section 23 via the connection line 105.

The data is transferred from the fiber to the transmission/reception control unit 22, subjected to serial-to-parallel conversion, modulated by the post-modulation/demodulation unit 21, and sent to the destination local data processing device via the connection line 101 (step 602).
. There are three responses: REJ F-AME reception, ACP FRAME reception, and no response.

First, in the case of REJ FFLAME reception (step 6
Y branch of 03) Processor 29 is (A2)' of memory 30
ii. The read timer 25 is set to step 18-604). After the time (A2) has elapsed, the timer 25 times out (step 605), and the processor 2
9, the processor 29 checks whether the number of timeouts is a predetermined number or not.
06), if it is not the specified number of times, the above step 601
The loop operation of -602-603-604-605-606-601 is repeated and the frame is retransmitted to the destination local data processing device at a certain time (A2), and when the retransmission reaches the specified number of times, the Y branch of step 606 is executed. The operation of step 609, that is, the operation of generating all the abnormality notification frames and notifying the sender of the abnormality that the frame cannot be sent to the destination, is performed via the ■ symbol in accordance with the flowchart of FIG.

ACP FRAMAMERAM upper case, step 603
If the ON branch or the Y branch of step 607 is passed, timer 2 is activated.
5. The frame transfer is completely stopped (step 608) and the frame transfer is completed.

If there is no response, the N branch of step 603, step 60
Timer 2 after a time period of 7 N pieces (N1) has elapsed.
5 times out (step 605), interrupts the processor 29, and all processors 29 check whether the number of timeouts has exceeded the predetermined number (step 606), and if it is not the predetermined number, the above-mentioned step 60
1-602-603-607-605-606-601
The loop operation is repeated to retransmit the frame to the destination local data processing device at every fixed time interval (AI), and when the retransmission reaches the specified number of times, the frame is retransmitted via the Y branch of step 606 to step 60.
The flowchart in FIG. 7 showing the operation of step 9, that is, the failure to generate an abnormality notification frame and send the frame to the destination, shows that the own station (
This shows the operation when sending a frame from a loop data transmission device (loop data transmission device) to another loop data transmission device.The frame includes frames originating from the local station and frames originating from the data processing device of the local station and passing through the local station. Contains.

When it becomes necessary to send all frames from the local station to another loop data transmission device R, the processor 29 temporarily waits while the local station is communicating with the other loop data transmission device, and after the communication is completed (step 700), the memory From 30 (All
) and (Ag3)*m, all time data are set in the timers 26 and 27, respectively (steps 701 and 7o2). Then, the operation of transmitting all frames in a loop is started (step 703). In other words, it acquires all transmission rights and transmits the frame (Y branch of step 704).
All time data is set in the (Axa)i read timer 28 from the memory 30 (step 7o5). As a response to frame transmission, REJFRAME is received as described above,
There are three cases of ACP FRAMERAM failure and no response.

If REJ FRAMERAM is upper (Y branch of step 706), the processor 29 sets the full read timer 28 (A14) of the memory 3o (step 707).

(14) The timer 28 times out after a certain amount of time has elapsed (step N branch of step 708 → step).

step 709), interrupts the processor 29, acquires the transmission right again and retransmits the frame (steps 702-703-704-705-706-70)
Repeat the loop operation of 7-708-709-702 RE
J FRAMERAM Starts the operation of retransmitting frames at fixed intervals ((A14)).

A, CP FRAMBt even after a certain period of time (Axt) has elapsed
- If the timer 26 times out without reception (step
(Y branch of step 708) Proceeds to step 714, and if the frame from the data processing device of the own station is being relayed instead of the frame transmitted by the own station (step N branch of step 714) Step 716) Timers 26, 27 and 2
Step 719) ends the data transfer operation. When transmitting a frame originating from the own station (step 71)
(Y branch of 4) It holds and memorizes that it is in an abnormal state (step 718) and stops the timers 26, 27 and 28f. Step 719) The data transfer operation ends.

ACP FRAMAMERAM upper case, i.e. step 70
If it passes through the N branch of 6 and the Y branch of step 710, if the frame is not transmitted from the own station (N branch of step 715), K is the data processing device image 26, 27 and 2 of the own station.
8 to end the data transfer operation.

If there is no response, the N branch of step 706, step 71
After the time (A13) has passed through the N branch of 0, the timer 28 times out (step.

Step 708 N & → Step 709) Interrupt the processor 29, acquire the transmission right again, and retransmit the frame. Steps 702-703-704-705 described above.
The loop operation of -706-710-708-709-702 is repeated, and after acquiring the transmission right, a retransmission operation is started every fixed time (A13) to retransmit the frame. Fixed time (Alt)
If the timer 26 times out without receiving ACP FR - AME even after the elapse of time, the process proceeds to step 708 via the Y branch. This operation is R, BJ FRAME
Since the operation is the same as that described above after the timer 26 times out after the time has elapsed (A11), the explanation will be omitted.

In order to send a frame to the loop, the transmission right must be acquired as described above, but the transmission right must be acquired within a certain period of time (A12
), the timer 27 times out (step 704, N branch), interrupts the processor 29, creates all transmission right frames, and sends them out to the loop.Step 712→Step 713) Sends the frame as described above. Start operation (steps 702-703-) f
The Rukoto. Even in this case, when (Alt) time elapses and the timer 26 times out (step 712
7), the data transfer operation is completed through steps 714 in the same manner as described above.

FIG. 8 is a flow diagram showing the operation when all frames addressed to the local loop data transmission device are received.

The received frame is usually a command requesting specified processing within the local station. IL command that specifies all the processing requested in the CTL field of the frame.
Condition A, address Al is a request to rewrite the required data in the INF field and the data stored in A2.
All conditions B when requesting to rewrite data stored in l
, address A12, all conditions C, address A13
and A, condition 14.

In the case of condition A (step 801), the time data TI' and T2 sent in the INF field are
0 at addresses A1 and A2, respectively (step 802), and in the case of condition B (step 803)
Store the time data T11'' of the F field at address 711111C of the Iz memory 30 (step 804), and in the case of condition C (step 805), store the time data Txz' of the INF' field at address A12 of the entire memory 30 (step 806). ), in the case of conditions (step 807), all time data T13' and T14' of the INF field are stored in addresses A13 and A14 of the memory 30, respectively. After decoding the command and performing the specified processing (step 809), when the frame is received from the loop (Y branch of step 810), the ACP F
RAME' (il--as it is returned as a response, the data transfer ends, and when the frame is received from the own data processing device (N branch of step 810), ACP F'RAME is sent to the data processing device. to end the data transfer operation.

With this operation, the j-loop data transmission device is powered on and initialized to (AI), (A2), and (All).

(A12), (Ata) and (71Vx 4 ) respectively at Tt.

T2. Tl l, 'rt 2. Tla and T1
4 and frames from all external devices set to TI' and T2', respectively.

Ti1', T12', T1B' and T14'
You can arbitrarily change specified loop data transmission device to these specified time data frame retransmission operation interval time.

Response time limits can be managed.

In this embodiment, as shown in FIG. 6, the response limit time is managed by a specified number of times, but the present invention is not limited to this. You can also.

As described above, the present invention includes the frame retransmission operation interval time,
This has the advantage that the response limit time can be set arbitrarily and the communication efficiency of the transmission system can be maintained at all altitudes.

[Brief explanation of drawings]

Figure 1 is a block diagram of a loop data transmission path, Figure 2 is a configuration diagram of a transmission frame, Figure 3 is a block diagram of an embodiment of the present invention, Figure 4 is a flow diagram of initial settings, and Figures 5 to 8 The figure is a flow diagram showing the procedure of frame processing and retransmission during frame transfer. In the figure, 1...Line, 2-7...Loop data transmission device, 8-13...Data processing device, 21
．． 24...Modulation/demodulation section, 22.23...
Transmission/reception control unit, 25, 26° 27.28...Timer, 29...Process, 30...
Memory, 101-110... Connection line. 111...Bus, 401-405, 501-5
1 to 601-609,700-719,801-810
...Steps and steps in the flow diagram. Fig. 1 #2 Concave Grass 3 En Japanese Patent Publication No. 59-30337 (9)

Claims (2)

[Claims] (1) In a plurality of loop data transmission devices connected to a loop line for data transmission between a plurality of data processing devices, storage means for storing all time data, and storage means for storing predetermined time data, respectively. initial setting means for writing to a predetermined address of the data processing means; writing means for rewriting time data stored in the storage means using time data supplied from the data processing device; first time data or second time data stored in the storage means in response to relaying of an information frame addressed to the station data processing device or from another station data processing device to the own station data processing device; is set, and third time data or fourth time data stored in the storage means is set in response to reception of an unreceivable frame from each of the destination devices, and the time specified by the set time data. a first time signal generating means that generates a first time signal when the first time signal has elapsed; information frame retransmission means that retransmits the information frame in response to the supply of the first time signal; a first time signal generation stop means for completely stopping the operation of the first time signal generation means in response to reception of a received optical frame from the apparatus. (2) The fifth time data or a second time signal generating means for generating a second time signal when the sixth time data is set and a time specified by the set time data has elapsed;
and second time limit signal generation stop means for transmitting a non-transmittable frame to the destination device in response to the supply of the time limit signal and stopping the operation of the first and second time signal generation means. A loop data transmission device according to claim (1).