JPS583438A - Data transmitting device - Google Patents

Abstract

PURPOSE:To realize a loop transmission system which has an improve circuit service and a simplified procedure of the transmission protocol, by applying a transmission procedure eliminating a retry due to the nonreply. CONSTITUTION:A data transmission/reception control part 307 gives a start to a circuit control part 309 when a command is given to the transmission of data. Thus the control part 309 controls a synchronizing frame circuit 301, an S-P converter 302 and a P-S converter 303 in place of a data transmission control part 307 during the data transmission service of the part 307. Therefore the information transmitted from another station and showing a data transmission request is stored in a receiving submemory 310. The control part 309 receives the information showing the data transmission request from the submemory 310 and then sends the answer information showing that a receiving memory 304 of the own station is busy back to the station that gave the above-mentioned transmission request.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applied to a data transmission system and relates to a data transmission device having a data transmission function and a line service function.

A data transmission system, such as a data way system, in which data transmission between data transmission devices is performed via a transmission path, generally includes a plurality of data transmission devices 11. ~lln and these data transmission devices 111~I
It has a configuration consisting of a pair of transmission lines L that connect ln in a ring (so-called loop connection). In such a system, a data transmission device 11. 11n serves as a monitoring device (monitoring station) to monitor the line and implement the line connection protocol. These operations are performed by firmware control, and therefore, if the specified device specified in Section t and other data transmission devices have the same basic configuration with only some differences in the firmware (microprogram) content. There are many. In addition, all data transmission equipment' 1 m
There is also a system in which the devices 11 to 11 have the same configuration with a monitoring function and the monitoring device end is set by switching a switch.

2 shows a schematic configuration of the data transmission devices 111 to IIn described above, in which 21 is a repeater equipped with a transmitter and receiver;
22 is a line interface. The line interface 22 detects the synchronization signal of rOIIkl when receiving data and assembles the data, and when transmitting data, divides the transmission data and outputs the data frame by frame. 2
3 is a control section. This control unit 23 controls the entire device, and is controlled by firmware to perform data transmission between data transmission devices, and a computer/terminal interface to which a computer and a terminal device are connected (both not shown). It was supposed to perform line services such as data transfer and line connections.

In such a conventional data transmission device, when there is a transmission request from another data transmission device during data transfer between the control section 23 and the computer/terminal interface, the control section 13
cannot return a response to the transmission request, which has the disadvantage of deteriorating line service. Generally, a data transmission device measures the time it takes for a response to be returned after sending a transmission request, and if a response is not returned after a predetermined period of time, a retransmission request is sent as a timeout ( retry). If there is no response even after reaching a predetermined number of retries, the data transmission device requesting transmission is either unresponsive due to an abnormality such as a disconnection of the line, or the computer
Diagnose whether there is no response due to a data transfer operation with the terminal interface. In other words, in the conventional data transmission protocol between data transmission devices, the number of attempts to transfer the same data increases, the wasted time in data transmission between the data transmission devices increases, and the diagnosis procedure and contents for non-response are complicated. there were.

The present invention has been made in view of the above circumstances.
Even during data transfer with an interface (or terminal), it is possible to quickly respond to data transmission requests from other data transmission devices, thereby improving line service and improving data transmission protocols between data transmission devices. The object of the present invention is to provide a data transmission device whose procedures can be simplified.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. This sixth embodiment is a case where it is implemented in a data transmission device C in a data way system as shown in Figure 1 (hereinafter referred to as station), and the same parts as in Figures 1 and 2 are Reference numerals are given and detailed explanations are omitted. Figure 3 shows the configuration of the station (data transmission equipment)-4
- The line interface 22 includes a synchronous frame circuit 301, a serial/serial data converter (hereinafter referred to as SPC) 302, and a serial/serial data converter (hereinafter referred to as PSC) 303. It is equipped with The synchronization frame circuit 301 has a known function of detecting a line synchronization signal and assembling data, and dividing the data and outputting the data frame by frame when transmitting data.

Reference numeral 304 is a reception memory in which parallel reception data converted and output from the SPCs o z is stored.The reception data stored in the reception memory 304 is transferred to the computer/terminal interface 400. Reference numeral 305 is a transmission memory in which transmission data transferred from the computer/terminal interface 400 is stored, and the transmission data stored in the transmission memo 9305 is transferred to the pscs o s. 306 is a memory for reception 304 and a memory for transmission 30 according to instructions from a data transmission/reception control unit 307, which will be described later.
This is a memory control unit that performs memory access control for 5.

307 is a data transmission/reception control unit. The data transmission/reception control unit 307 has a ROM in which a firmware C microprogram is stored and a microprocessor (none of which is shown) that performs firmware control based on the contents of this ROM (firmware). , inter-station data transmission, and reception memory 304, transmission memory 305, and computer-terminal interface 400.
Provides data transfer services between Further, the data transmission/reception control section 307 performs switching control for switching devices 312 to 316, which will be described later, and also activates a line control section 309, which will be described later, during the data transfer service. 308 is a data transmission/reception control unit 307 (
This is a control memory that stores information flags used by the firmware.

309 is a line control section. The line control unit 309 has an unillustrated ROM and a microprocessor like the data transmission/reception control unit 307, and the reception memory 3
0'4, during the data transfer period between the transmission memory 305 and the computer/terminal interface 400, line service is provided under firmware control by the microprocessor.

This line service plays an auxiliary functional role in data transmission between stations, such as line connection, reception of data transmission request information, and transmission of response information.

Note that operations such as receiving data transmission request information and transmitting response information during periods other than the data transfer period are performed by the data transmission/reception control unit 907. 310 and 311 are reception memories 304, respectively.
．． These are a reception sub-memory and a transmission sub-memory that serve as an alternative memory to the transmission memory 305. Information flags used by (the firmware of) the line control unit 309 are stored in the reception submemory 310 and the transmission submemory 311.

CLa is a control signal line for the line interface 22 (synchronization frame circuit 301, SPCj 02, PSC 303, etc.), CLb is a control signal line connected to the data transmission/reception control section 301, and CLc is a control signal line connected to the line control section 309. It's a line. BtJ8
, a to BU81° are 8PCs 302 and reception memory 304. When transmitting data connected to the reception sub-memory 310, BUS,...~BUS! Otoma each PS
C: t o : t is the time of data transmission connected to the transmission memory 305 and the transmission sub-memory 311. BUS
sa-BUS,. are each receiving memory 30.4
, data transmission/reception control unit 307゜data bus, BUD, a-BU connected to the computer/terminal interface 400
D and c are data transmission times connected to the transmission memory SOS, the data transmission/reception control unit 307 and the computer/terminal interface 400, respectively.

312 connects the control signal line CLa to the control signal line CLb.
, a switching device for switching connection to either one of CLc, 3
13 is the data bus BUS, a is the data bus BUS,
A switch 314 connects data bus BU8 to data bus B, and connects a to data bus B.
This is a switch that connects to either one of the US, b, and BUS. 315 is a switch that switches and connects BUS and a to either data bus BUS, b, or BtJ8ac during data transmission; 316 is a data path BU84g
ヲy'' -9 Has BUS, b, BUS, c (7) This is a switch that switches and connects to one side.

Next, the operation of the configuration shown in FIG. 3 will be explained. Now, data transmitted from another station via, for example, a transmission path is received by the repeater 21 and sent to the synchronization frame circuit 30J.
, 8PC302 via the data bus BU81. Assume that it is output above.

At this point, control signal line CLa is connected to control signal line CLb by switch 312.

The data noise BU81m is connected to the data bus BUS, b by the switch 313, and the data bus BUD
t, a are the switch 314ζ-therefore data noise BU8
, b. In addition, the data bus Bus, a
, BUS 4 a is switched '83115, 316 respectively.
data bus BUS m b , BUS 41)
It is connected to the. Data bus BU8. ．． The received data of h is transferred to switch 313.h. The received data is input to the receiving memory 304 via the data bus BIJ81b, and the received data is received and stored in the memory 304 under write access control of the memory control unit 306 that operates in accordance with instructions from the data transmission/reception control unit 307.

In this way, when all received data is stored in the reception memory 304, the data transmission/reception control unit 307
12 to 315 are switched and controlled. As a result, the control signal line CLa becomes the side axis signal line CLc, and the data bus B
US1a connects data bus 808, C to data bus B
The US ta is switched and connected to the data nodes BUS, c, and the data bus BUS sa is connected to the data bus 9, BUS c. The data transmission/reception control section 307 then gives an instruction to the memory control section 306 to transfer the received data. As a result, the received data stored in the reception memory 306 is read out from the reception memory 304 under the read access control of the memory control unit 306, and is transferred to the data bus BUS, a, the switch 315. Data bus BUS, c
The data is primarily transferred to the computer/terminal interface 400 via the computer/terminal interface 400. Further, the data transmission/reception control unit 307 activates the line control unit 309 when issuing the above-mentioned data transfer instruction. As a result, the line control unit 309 sends s 07 , 8PCs o 2 . Control P2O3os.

Therefore, during the period of data transfer from the receiving memory 304 to the computer/terminal interface 400, the received data from other stations is transferred to the data station BU8. ．． ．． Switcher 3
13. The data is stored in the reception sub-memory 310 via the data BIJSIC. Therefore, if information indicating a data transmission request is sent from another station during the data transfer period described above, the information is stored in the sub-memory 310 of the receiver 4. The line control unit 309 takes in the information indicating the data transmission request from the reception sub-memory 310, confirms that it is a data transmission request, and then responds to the information by indicating that the reception memory 304 is in a busy state. Sub-memory 311 for sending response information
Output from. This response information is sent to the data bus BUS,...
.

Switch 314. The data is inputted to the line interface 22 via the data nozzle BUS, . In this case, the relevant station does not perform the conventional retry due to no response, and the reason for the second dark response is due to an abnormality such as line disconnection. There is no need to execute an inter-station data transmission protocol with a complicated procedure for diagnosing whether the problem is caused by the condition, and the procedure of the data transmission protocol is simplified.

Next, it is assumed that all of the received data stored in the receiving memory 304 and received for 1 and t have been transferred to the computer/terminal interface 400. The data transmission/reception control unit 307 switches and controls the switches 312 to 315 in response to the completion of data transfer. This (2) the control signal line CLa becomes the control signal line CLb again, the data bus BU8 t, becomes the data bus BU8.B <-, the data bus BU8, a becomes the data bus BtJS again, and the data bus BUS
, a are again switched and connected to the data nozzle BUS3bl2. The data transmission/reception control unit 307 stops the control operation of the line control unit 309. Note that a flag indicating whether or not the line control unit 309 is in a busy state is provided, and when the line control unit 309 is in a transmitting/receiving state C2,
The data transmission/reception control unit 307 switches the switches 312 to 31 after detecting that the P/S state has been canceled by the flag.
It is preferable to perform the switching control described in No. 5.

Next, the operation during data transmission will be explained.

It is assumed that a data transmission request is given to the data transmission/reception control unit 307 from the computer/terminal interface 400.

The data transmission/reception control section 307 switches and controls the switching devices 312, 313, 314, and 316 in response to this data transmission request.

As a result, the control signal line CLa is connected to the control signal line C
To Lc, data bus BU8, , is data bus BU
The data bus T3TJS is connected to the data bus BUS.
Start. Then, the transmission data is stored in the transmission memory 305.
If information indicating a transmission request is sent from another station during the period during which the station is transferring and storing the information, the information is stored in the reception sub-memory 310 as in the case where the received data is being transferred. Ru. After the line control unit 309 takes in the above information from the reception sub-memory 310 and confirms that it is a data transmission request, it sends a memo for transmission as a response to the information. The transmission sub-memory 311 outputs response information indicating that the J 305 is in the Binoy state ζ2. This response information is transmitted to the corresponding station that issued the data transmission request through the same process as described above. In this state, data is transferred from the computer/terminal interface 400 to the transmission memory 305 to
La is connected to the control signal line CLb again, and the data bus BUS
1a is again the data bus BIJ8, b is the data bus BT18□ is again the data bus BU8, and C is the data bus BTJ8. a are again switched and connected to the data bus BUS4c.

By the way, when the monitoring station starts up the system,
When line disconnection is detected, a line connection protocol is implemented with each station, and each station is connected to the line one by one. In this embodiment, it is possible to have the line control section 309 perform such a line connection protocol, and the data transmission/reception control section 307 can control the computer/terminal interface 400 during the execution of this line connection protocol. services can be provided. In other words, in the past, when a line abnormality occurred, the control unit shown in Figure 2 concentrated on implementing the line connection protocol in order to restore the line, causing a problem in which service to the computer/terminal interface deteriorated. According to the example, such problems can be definitely solved.

In the above embodiment, the case where the present invention is applied to a data transmission device # (station) in a so-called data way system is explained, but it is clear that the present invention can be applied to data transmission devices of various systems such as a multi-drop type data transmission system. .

As detailed above, according to the data transmission equipment of the present invention,
Even while data is being transferred to a computer (or terminal) interface, it is possible to quickly respond to data transmission requests from other data transmission devices, improving line service and reducing data transmission time between data transmission devices. - The col procedure can be simplified.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the system configuration of a general data way system, FIG. 2 is a block diagram showing a schematic configuration of conventional data transmission breakage in the data way system, and FIG. 3 is a data transmission device of the present invention. FIG. 2 is a block diagram showing one embodiment of the present invention. 21... Repeater, 22... Line interface,
304... Memory for reception, 305... Memory for transmission, 307... Data transmission/reception control unit, 309... Line control unit, 310... Reception sub-memory, 311... Transmission sub-memory'), 312-316...Switcher, 4o. ...Computer/terminal interface, L, L...Transmission line, CLa % CLc...Control signal line, BU
D, a-BUD, c. BtJSta~BUS, c, BUD, a~BUS,,
, BUS,, ~BUS,. ...Data bus. Applicant's agent Patent attorney Takehiko Suzue 1st r? J w12 figure

Claims (2)

[Claims] (1) A transmitting/receiving memory in which received data received by the ≠-data transmitting/receiving unit and transmitting data transferred from the computer (or terminal device) connected to the own device are stored, and this transmitting/receiving memory and the computer ( or a terminal device) side and a data transmission/reception control unit that performs data transmission services with other data transmission devices; 1. A transmitting/receiving system in which at least received data and response information to other data transmission devices are stored. L is activated by the data transmission and reception control unit when the data transmission and reception control unit starts the data transfer service, and during the data transmission service period,
Under the control of the line control unit that performs the line service and the data transmission and reception control unit, the data transmission and reception unit is switched to either the F delivery/reception memory or the transmission/reception submemory at the start and end of the L data transfer service. Under the control of the connected @1 switching unit and the data transmission/reception control unit, the transmission/reception memory is transferred to either the data transmission/reception control unit or the computer (or terminal device) at the start and end of the data transfer service. and a second switching section that switches and connects to one of the lines.
During the data transfer service period of the data transmission/reception control unit, data is sent from another data transmission device, and the data is stored in the transmission/reception submemory via the data transmission/reception unit and the first switching unit. , the data transmission device is characterized in that, when the data transmission/reception is performed, the corresponding response information is transmitted to the corresponding data transmission device via the first switching section and the data transmission/reception section. (2) A patent claim characterized in that the data sent from another data transmission device during the data transfer service period is information indicating a data transmission request, and the response information is information indicating a busy state of the transmitting/receiving memory. The data transmission device according to item 1.