JP3961128B2 - Data communication method and transmitter / receiver - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a data communication method and apparatus, and more particularly to a data communication method and apparatus that further simplify the data structure of transmission data and reduce the processing time required for data communication.
[0002]
[Prior art]
In the conventional data communication protocol, header information such as a “protocol header” is provided in the frame (usually the head portion) obtained by converting transmission data into a communication configuration, and the frame is identified by a frame identifier in the protocol header. It was identified whether it was a “command frame” or a “data frame”.
[0003]
FIG. 9 is a schematic explanatory view showing such a conventional data communication system. In FIG. 9, reference numeral 1 denotes conventional transmission data (hereinafter referred to as “transmission data” in this specification is a command frame or data frame transmitted in each data exchange in one data communication processing operation). It is a figure which shows roughly an example of the flame | frame which is. This frame 1 is an example of a command frame. A protocol header 2 is provided at the head of the frame 1 and data of “command” is set as an identifier of this frame, indicating that this frame is a command frame. Next, a command code area 3 is provided, and in this command code area 3, data of “transmission” is set to clearly indicate that this command frame is a notification of transmission. Further, a parameter area 4 is provided in the next portion, and information such as the total data length of data to be transmitted is stored in the parameter area 4.
[0004]
In transmitting data, first, the data transmitting side notifies that data will be transmitted. At this time, the command frame 1 is sent as transmission data to the data receiving side via the communication line. On the data reception side, the transmitted command frame 1 is stored in the reception buffer 15, and then the frame identifier set in the protocol header 2 of the reception frame 1 is checked. Since this frame 1 is a “command frame”, the command Refer to the code and recognize that it is a send command.
[0005]
Thereafter, the data receiving side notifies that its own device is ready to receive data. For this notification, a command frame is sent from the data receiving side to the data transmitting side. Reference numeral 5 is a diagram schematically showing an example of a command frame sent from the data receiving side to the data transmitting side. Like the command frame 1, the command frame 5 is provided with a protocol header 6 at the head thereof, and data of “command” is set as an identifier of the frame, indicating that this frame is a command frame. Yes. Next, a command code area 7 is provided, and “OK” data indicating that data is ready to be received is set in the command code area 7. On the data transmission side, the frame identifier set in the protocol header 6 of the transmitted command frame 5 is checked, and since this frame is a “command frame”, the command code is referred to and it is recognized that it is a received OK command. To do.
[0006]
Thereafter, data to be transmitted by the data communication processing service (hereinafter referred to as “process data”) is transmitted from the data transmission side to the data reception side. Reference numeral 8 is a diagram schematically showing an example of a data frame sent from the data transmission side to the data reception side. As in the case of the command frames 1 and 5, the command frame 8 is provided with a protocol header 9 at the head thereof, and data indicating “data” is set as an identifier of the frame. It is shown that. Thereafter, a data area 10 is provided, and processing data is set in the data area 10. While the frame length is usually set to a value within a predetermined range, the amount of processing data is often large. To transmit all processing data, send data This processing data is blocked at an appropriate length on the side and divided into a plurality of frames such as a first data frame 8, a second data frame 11,..., An nth data frame (final frame) 12. Sent. The first data frame 8 stores the block 1 as data, the second data frame 11 stores the block 2 as data, and the nth data frame 12 stores the block n as data. All the data frames 8, 11, and 12 have the same frame configuration.
[0007]
At the data receiving side, first the first data frame 8 transmitted is stored in the reception buffer 15, and then the frame identifier set in the protocol header 9 of the reception frame 8 is checked. This frame 8 is a “data frame”. Therefore, the data of block 1 is transferred to the editing buffer 16. On the data reception side, the second data frame 11 transmitted next is stored in the reception buffer 15, and then the frame identifier set in the protocol header 9 of the reception frame 11 is checked. Therefore, the data of the block 2 is transferred to the editing buffer 16. In the editing buffer 16, the received data is added by successively storing the block 2 after the previous block 1. Then, the editing buffer 16 accumulates the block data up to the unit for writing to the file 17 and the like, and writes it to the file 17 and the like at once.
[0008]
[Problems to be solved by the invention]
However, according to the conventional data communication method as described above, since the protocol header is provided at the head of the frame for communication, the transmission side generates a frame by combining the protocol header and the transmission data. Processing is necessary, and the receiving side has a problem that it takes time to analyze the protocol header of each frame and to perform processing (editing processing) of removing only the transmitted data by removing the protocol header. In addition, since the protocol header is added to the data frame, there is a problem that the actual data area is narrowed, the throughput is not increased, and the transfer speed is not increased particularly in a powerless CPU machine such as a portable information terminal. . Especially in recent high-speed data communication, data transfer using direct memory access (DMA) is the mainstream, and it is difficult to simultaneously perform data reception and protocol header analysis. It has become an inevitable problem.
[0009]
The present invention has been made in view of such conventional problems, and an object of the present invention is to make it possible to identify whether a frame of transmission data is a data frame or a command frame without requiring a protocol header in the frame. Another object of the present invention is to provide a data communication method and apparatus that simplify protocol header check processing.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides In a data communication method for transmitting and receiving data by assigning different frame lengths to a command frame and a data frame using frame synchronization, on the transmission side, the transmission data is blocked by the data frame length and divided into a plurality of frames. The transmission side has a reception data length counter, a reception buffer, and a file writing means. The reception data length counter determines the type of frame based on the frame length, and is transmitted when it is determined as a data frame. The first block data of the first data frame is accumulated in the reception buffer, the reception data length counter is updated by the length of the first data frame length, and the data frame transmitted from the next time onward is also updated. Block data is added to the reception buffer following the first block data. The received data length counter is updated by adding to the first data frame length, the block data is accumulated up to the unit of writing to the file, and written to the file all at once, or all block data is received. After receiving is completed, the received data is written to the file all at once. The summary is as follows.
[0011]
This allows each frame type to be used without using a fixed area such as a protocol header inside the frame. Different By assigning the frame length, the frame type can be recognized, and reception and response operations corresponding to the frame can be performed. Also, Since the data sent to the receive buffer is automatically accumulated, it is not necessary to extract the data to be received from the received data, edit it, and edit the sent data. Can save, The amount of data flowing on the communication line can be reduced to increase the data communication speed. Furthermore, by deleting the data area such as the protocol header from the frame, the data processing speed can be increased, and the overall throughput can be improved.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The invention according to claim 1 of the present invention provides In a data communication method for transmitting and receiving data by assigning different frame lengths to a command frame and a data frame using frame synchronization, on the transmission side, the transmission data is blocked by the data frame length and divided into a plurality of frames. The transmission side has a reception data length counter, a reception buffer, and a file writing means. The reception data length counter determines the type of frame based on the frame length, and is transmitted when it is determined as a data frame. The first block data of the first data frame is accumulated in the reception buffer, the reception data length counter is updated by the length of the first data frame length, and the data frame transmitted from the next time onward is also updated. Block data is added to the reception buffer following the first block data. The received data length counter is updated by adding to the first data frame length, the block data is accumulated up to the unit of writing to the file, and written to the file all at once, or all block data is received. After receiving is completed, the received data is written to the file all at once. Without using a fixed area such as a protocol header inside the frame. Different Assign frame length T It has the effect of recognizing the frame type and performing reception and response operations according to the frame.
[0013]
The invention according to claim 2 of the present invention is the data communication method according to claim 1, The frame length for multiple types of defined data frames is set to an integer multiple of a predetermined reference value, and whether it is a data frame can be determined by whether the frame length is an integral multiple or not. Processing speed becomes faster It has the action.
[0014]
The invention according to claim 3 of the present invention comprises 1 In the data communication method described, It is detected whether the frame length of the received frame is an integral multiple of a predetermined reference value, and from this detection result, the received frame is recognized as a data frame, and reception processing is performed. It is possible to determine whether it is a data frame by whether or not is an integer multiple, and the reception processing speed is increased. It has the action.
[0015]
The invention according to claim 4 of the present invention is In a data transmission / reception apparatus that assigns different frame lengths to a command frame and a data frame and performs data communication using frame synchronization, a transmission side generates a frame generation unit that blocks transmission data by the data frame length, and generates the data by the blocking A transmission unit that transmits a plurality of frames, and a reception side includes a reception data length counter unit, a reception buffer, a control unit, and a file writing unit. When the data received by the reception data length counter is a data frame, the control unit accumulates the first block data of the first data frame in the reception buffer, and receives the reception data. Count the data length counter unit by the length of the first data frame Newly, the block data of the data frame transmitted after the next is stored continuously in the reception buffer unit, and the count of the reception data length counter unit is continuously updated by the data length, The reception buffer sequentially accumulates block data, and the control unit accumulates block data up to a unit for writing to a file, or writes to a file in a lump after reception of all block data is completed. By simply checking the frame length, the frame type can be recognized, and reception and response operations can be performed according to the frame, increasing the reception processing speed. It has the action.
[0016]
The invention according to claim 5 of the present invention is 5. The data transmission device according to claim 4, wherein the transmission control means sets the frame length for a plurality of types of defined data frames to an integral multiple of a predetermined reference value, and the frame length is an integral multiple. Whether it is a data frame can be determined by whether or not it is, and the reception processing speed increases. It has the action.
[0032]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0033]
(Embodiment 1)
FIG. 1 is a block diagram showing an example of a data communication system between a collection / distribution device and a portable terminal device, showing the configuration and connection relationship of a data transmission / reception device for realizing a data communication method according to the present invention. In FIG. 1, 21 is a personal computer, 22 is a collection and distribution device, and 23 is a portable terminal device. The personal computer 21 serves as a central processing unit that generates data input to the collection and distribution device 22 and controls the operation of the collection and distribution device 22. The data collection / delivery device 22 transmits / receives data to / from the mobile terminal device 23. Since the portable terminal device 23 is carried by each person in charge, a plurality of data 23a, 23b,. The collection / delivery device 22 controls communication means 24 for transmitting / receiving data to / from the personal computer 21, a memory 25 in which various data and programs are stored, and data writing and reading operations to the memory 25. A DMA (direct memory access) controller 27 and a control unit 28 for controlling the operation of each of these functional units are provided.
[0034]
The control unit 28 includes a frame generation unit that converts data to be transmitted into a frame structure, a data detection unit that determines whether the transmission data is a command or processing data, and a frame generation unit based on the detection result of the data detection unit. A frame length data storage memory for storing frame length data assigned to the generated frame. The portable terminal device 23 performs communication means 29 for transmitting / receiving data to / from the collection / distribution device 22, a memory 30 in which various data and programs are stored, and data writing and reading operations to the memory 30. DMA controller 31 to be controlled, storage means 32 such as a hard disk in which various files and processing data are stored, an input unit 33 such as a touch panel for inputting various data, a liquid crystal in which data is displayed in the form of an image, etc. Display unit 34 and a control unit 35 for controlling the operation of each of these functional units.
[0035]
The control unit 35 includes frame detection means for determining whether the received data is a command frame or a data frame. As an example, this frame detecting means is constituted by a received data length counter 50 for detecting the frame length of a received frame and determining whether the frame is a command frame or a data frame. The control unit 35 also includes a total data length register 51 that temporarily stores the total data length of data to be communicated. The personal computer 21 and the collection / delivery device 22 are connected by a communication line 36, and the collection / distribution device 22 and the portable terminal device 23 are connected by a communication line 37. These communication lines 36 and 37 can use various forms such as a wired line and a wireless line.
[0036]
The operation of the data transmitting / receiving apparatus having such a configuration will be described. Here, the collection / delivery device 22 is a data transmission device, and the portable terminal device 23 (which may be any of 23a, 23b, and 23n) is a data reception device.
[0037]
FIG. 2 is a diagram schematically showing a state in which a frame is generated for data communication in the present embodiment and transmitted and received between the transmission side and the reception side through the communication line. In the data collection / delivery device 22, when data is transmitted, it is notified that data will be transmitted. At this time, the command frame is sent as transmission data to the data receiving side via the communication line. Reference numeral 41 is an example of a frame which is transmission data in the present invention. This frame 41 is an example of a command frame, and a protocol code is not provided at the head of the frame 41 but a command code area 42 is provided. In the command code area 42, “transmission” data is set to clearly indicate that this command frame is a notification of transmission. Further, a parameter area 43 is provided in the next portion, and information such as the total data length of data to be transmitted is stored in the parameter area 43. In creating the command frame 41, in the collection and distribution device 22, the data detection means provided in the control unit 28 detects whether the transmission data is a command or processing data, and the detection result is displayed in the frame. Notify the generation means. Based on the detection result from the data detection means, the frame generation means allocates a fixed frame length for each frame type according to the type of frame such as a command frame or a data frame, and the frame length is stored from the frame length data storage memory. Data is read to generate a frame having a different frame length for each frame type.
[0038]
On the mobile terminal device 23 side, the transmitted command frame 41 is stored in the reception buffer 15, and then the reception data length counter 50 provided in the control unit checks the frame length of the reception frame 41. Since it is a “command frame”, the command code is referenced to recognize that it is a transmission command. Similarly, the total transmission data length register 51 provided in the control unit holds “total transmission data length”.
[0039]
Thereafter, the mobile terminal device 23 notifies that its own device is ready to receive data. For this notification, a command frame is sent from the portable terminal device 23 to the data transmission side. Reference numeral 44 is an example of a command frame sent from the portable terminal device 23 to the collection and distribution device 22. Similar to the command frame 41, the command frame 44 is provided with a command code area 45 without a protocol header at the top thereof. In the command code area 45, “OK” data indicating that data is ready to be received is set. On the data transmitting side, the frame length of the transmitted command frame 44 is checked, and since this frame is a “command frame”, the command code is referred to and it is recognized that it is a received OK command.
[0040]
Thereafter, processing data to be transmitted by the data communication processing business is transmitted from the collection and distribution device 22 to the portable terminal device 23. FIG. 3 is an operation explanatory diagram for explaining the data frame creation and transmission operation of block 1 in the present embodiment. In this figure, reference numeral 46 is an example of a data frame sent from the collection / delivery device 22 to the portable terminal device 23. As in the case of the command frames 41 and 44, the data frame 46 is not provided with a protocol header at the beginning thereof, and is composed only of the data area 47. Processing data is set in the data area 47. In the data collection / delivery device 22, as in the case described above (when creating a command frame), the data detection means provided in the control unit 28 determines whether the transmission data is a command or processing data. And the detection result (this time is processing data) is notified to the frame generation means. The frame generation unit allocates a frame length corresponding to the data frame based on the detection result from the data detection unit, reads out the frame length data for the data frame from the frame length data storage memory, and generates a data frame. The frame length of this data frame is different from the frame length of the previous command frame.
[0041]
In order to transmit all the processed data in a frame, the collection / distribution device 22 blocks the processed data with the given frame length, and the first data frame 46 and the second data frame 47 (block 2). ,..., N-th data frame (block n: final frame) 48, and so on. FIG. 4 is an operation explanatory diagram for explaining the data frame creation and transmission operation of block 2 in the present embodiment, and FIG. 5 is an operation for explaining the data frame creation and transmission operation of block n in the present embodiment. It is explanatory drawing. The first data frame 46 stores block 1 as data, the second data frame 47 stores block 2 as data, and the nth data frame 48 stores block n as data. All the data frames 46, 47, and 48 have the same frame configuration.
[0042]
In the mobile terminal device 23, first the first data frame 8 transmitted is stored in the reception buffer 15, and then the reception data length counter 50 provided in the control unit 35 checks the frame length of the reception frame 46, Since this frame 46 is a “data frame”, the data of block 1 is stored in the reception buffer 16. The reception data length counter 50 is updated by the data frame length.
[0043]
Next, the mobile terminal device 23 stores the second data frame 47 transmitted next in the reception buffer 15, and then the reception data length counter 50 checks the frame length of the reception frame 47. Is a “data frame”, it is added by continuously storing block 2 next to block 1 in the reception buffer 16. The reception data length counter 50 is updated by the data frame length.
[0044]
In this manner, the data frame is transmitted also for each block from block 2 to block n, and the received data block is sequentially stored in the reception buffer 15 on the portable terminal device 22 side. The length counter 50 is updated by the data frame length. The reception buffer 15 accumulates the block data up to the unit for writing to the file 17 and the like, and writes the data to the file 17 and the like collectively. Alternatively, after the reception of all the data up to block n is completed, the received data is collectively written into the file 17 or the like.
[0045]
FIG. 6 is a flowchart for explaining a data reception operation in the mobile terminal device 23. When the data reception process is started, a frame reception waiting state is entered in a processing step (hereinafter simply referred to as step) ST61. When a frame is received, it is checked whether the frame length of this frame is that of a command frame (step ST62). If it is that of a command frame, whether or not the command code is “send”. Is checked (step ST63). If the command code is “transmission” in this check process, the total transmission data length is held in the register 51 (step ST64), and the process returns to step ST61. If the command code is not “transmission”, command processing other than transmission is performed (step ST65), and the process returns to step ST61.
[0046]
On the other hand, if the frame length of the received frame is not that of the command frame in the check process of step ST62, it is checked whether or not the frame length of this frame is that of the data frame (step ST66). If not, the protocol abnormality process is performed (step ST67), and the series of reception operations is terminated. On the other hand, if the frame length of the received frame is that of the data frame in step ST66, the frame length is added to the received data length counter 50 (step ST68), and the value of the received data length counter 50 is equal to or greater than the total transmission data length. Is checked (step ST69). If the value of the reception data length counter 50 is not equal to or greater than the total transmission data length, the process returns to step ST61. On the other hand, if the value of the reception data length counter 50 is equal to or greater than the total transmission data length, Data corresponding to the total transmission data length is written in the file 17 or the like (step ST70), and a series of reception operations are terminated.
[0047]
FIG. 7 is a diagram showing another embodiment of the present invention. In this embodiment, when the frame is a command frame, a fixed frame length is assigned to each command type, and a frame having a different frame length is generated for each command type. In the example of FIG. 7, when the frame length is 1 byte, it represents a reset command frame, and when the frame length is 2 bytes, it represents a lamp lighting command frame. When the frame length is 3 bytes, it indicates a lamp turn-off command frame, and when the frame length is 4 bytes, it indicates a data transmission command frame. Finally, when the frame length is 2048 bytes, it represents a frame of transmission data. In this case, it is preferable to assign a shorter frame length to a frame of a command that is used more frequently. As a result, the amount of data flowing on the communication line can be further reduced.
[0048]
Also, a plurality of types of frame lengths for data frames may be defined, and when a frame is a data frame, a frame may be generated by selecting an appropriate frame length according to the transmission data length. This makes it possible to efficiently perform data block division and increase communication efficiency. Further, when a frame having a length other than the defined frame length is received, it can be immediately recognized that the communication is abnormal, and the time required for the communication check can be shortened.
[0049]
Furthermore, the frame length for a plurality of types of defined data frames can be set to an integer multiple of a predetermined reference value. By doing this, it is possible to recognize a data frame by checking whether the frame length is divisible by a certain value.
[0050]
It is also possible to set a rule that a frame smaller than a predetermined frame length is a command frame and a frame longer than the predetermined frame length is a data frame, and a frame for each frame type can be generated according to this rule. This is because the command data usually requires a small amount of data, and therefore the frame length is also small.
[0051]
FIG. 8 is a flowchart for explaining the command processing operation when a fixed frame length is assigned to each command type as described above and a frame having a different frame length is generated for each command type. When this command processing is started, frame reception waiting processing is first performed (step ST81), and when a frame is received next, a frame length check is performed (step ST82). Then, as described with reference to FIG. 7, when the frame length is 1 byte, it is determined that the frame is a reset command frame, a reset process is executed (step ST83), and then the process returns to step ST81. When the frame length is 2 bytes, it is determined that the frame is a lamp lighting command frame, lamp lighting processing is executed (step ST84), and then the processing returns to step ST81. If the frame length is 3 bytes, it is determined that the frame is a lamp turn-off command frame, lamp turn-off processing is executed (step ST85), and then the process returns to step ST81. Next, when the frame length is 4 bytes, it is determined that the frame is a data transmission command frame, data transmission processing is executed (step ST86), and then the processing returns to step ST81. If the frame length is 2048 bytes, it is determined that the frame is a frame of transmission data, data storage processing is executed (step ST87), and then the processing returns to step ST81. Finally, when the frame length is not any of the above, it is determined that there is a communication abnormality, a communication abnormality process is executed (step ST88), and then the process returns to step ST81.
[0052]
【The invention's effect】
As described above, according to the present invention, when performing data communication using frame synchronization, a fixed frame length is assigned to each frame type according to the type of frame such as a command frame or a data frame. Since a frame having a different frame length for each type and without header information is generated, and this frame is transmitted and received, the frame is not used within the frame without using a fixed area such as a protocol header. By assigning a fixed frame length for each type, it becomes possible to recognize the frame type and perform reception and response operations according to that frame, reducing the amount of data flowing on the communication line and reducing the data communication speed Can be raised. Further, by deleting the data area such as the protocol header from the frame, it is possible to increase the data processing speed, and various effects can be obtained such as improvement of the overall throughput.
[Brief description of the drawings]
FIG. 1 is a block diagram showing the overall configuration of a data communication system according to an embodiment of the present invention.
FIG. 2 is an operation explanatory diagram for explaining creation, transmission, and response operation of a command frame in the embodiment.
FIG. 3 is an operation explanatory diagram for explaining a data frame creation and transmission operation of block 1 in the embodiment;
FIG. 4 is an operation explanatory diagram for explaining a data frame creation and transmission operation of block 2 in the embodiment;
FIG. 5 is an operation explanatory diagram illustrating the creation and transmission operation of a data frame of block n in the embodiment.
FIG. 6 is a flowchart for explaining a data reception processing operation in the embodiment.
FIG. 7 is a diagram illustrating a frame configuration according to another embodiment of the present invention.
FIG. 8 is a flowchart for explaining a frame reception processing operation in the embodiment;
FIG. 9 is an operation explanatory diagram illustrating frame configuration, transmission, and response operation according to a conventional data communication method.
[Explanation of symbols]
21 PC
22 Collection and distribution equipment
23 Mobile terminal device
24, 27, 29 Communication means
25, 30 memory
26, 31 DMA controller
28, 35 Control unit
32 hard disk
33 Input section
34 Display section

Claims (5)

In a data communication method for transmitting and receiving data by assigning different frame lengths to a command frame and a data frame using frame synchronization,
On the sending side,
Blocking transmission data with the data frame length;
Send in multiple frames,
On the receiving side,
A reception data length counter, a reception buffer, and file writing means, wherein the reception data length counter determines a frame type based on the frame length;
When the data frame is determined, the first block data of the transmitted first data frame is accumulated in the reception buffer, the reception data length counter is updated by the amount corresponding to the first data frame length, and The block data is stored in the reception buffer after the first block data is added and stored from the data frame transmitted thereafter, and the reception data length counter is updated and added to the first data frame length, A data communication method characterized by accumulating block data up to a unit for writing to a file and writing it to a file at once, or writing received data to a file at a time after reception of all block data is completed .  2. The data communication method according to claim 1, wherein a frame length for a plurality of types of defined data frames is set to an integral multiple of a predetermined reference value. According to claim 1, wherein the frame length of the received frame and performing detection and reception processing the received frame from the detected result is confirmed that the data frame whether an integer multiple of a predetermined reference value Data communication method. In a data transmitting / receiving apparatus that assigns different frame lengths to a command frame and a data frame and performs data communication using frame synchronization,
On the sending side,
A frame generator that blocks transmission data at the data frame length;
A transmitter for transmitting a plurality of frames generated by the blocking;
Have
On the receiving side,
A reception data length counter unit, a reception buffer, a control unit, and a file writing unit;
The received data length counter unit determines the type of frame based on the frame length,
When the control unit determines that the data received by the reception data length counter unit is a data frame, the control unit accumulates the first block data of the first data frame in the reception buffer, and counts the reception data length counter unit Is updated by the length of the first data frame length, the block length of the data frame transmitted after the next is stored in the reception buffer section, and the count of the reception data length counter section is stored. , And continue to update
The reception buffer sequentially accumulates block data,
A data transmitting / receiving apparatus, wherein the control unit accumulates block data up to a unit for writing to a file, or writes the data to a file in a lump after reception of all the block data is completed. 5. The data transmission / reception apparatus according to claim 4 , wherein the transmission control means sets the frame length for a plurality of types of defined data frames to an integral multiple of a predetermined reference value.

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