JPH08251253A - Start-stop type data transmission method - Google Patents

Abstract

PURPOSE: To match respective data transmission speeds by judging a transmission side data transmission speed by reception state information decided by the data transmission speeds set on transmission and reception sides. CONSTITUTION: Transmission speed judgement data are transmitted from a transmission side data transmitter 1 to a reception side data transmitter 2 by a transmission speed judgement data transmission part 5a. They are recognized in a transmission speed judgement data recognition part 10a and judged in a judgement part 10b by using a judgement table 11. As a result, when the transmission speeds set on the transmission and reception sides are different, a transmission speed setting part 10d changes the speed on the reception side by the table 11. Then, response data are transmitted to the transmitter 1 by a response part 10c. Thus, in a data transmission part 5e, the send-out of transmission data main body from the transmission side, the confirmation response of the reception side, the send-out of the end data of the transmission side and the ending confirmation send-out of the reception side are performed and data transmission is ended.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a start-stop data transmission method, and more particularly, to a start-up data transmission method which is an improved method of adapting a data transmission rate between transmitting and receiving devices.

[0002]

2. Description of the Related Art For example, in data transmission between computers forming a network, data cannot be normally transmitted if the communication speed (that is, the transmission speed or the transmission clock) between the transmitting side and the receiving side is different. I am trying to match.

However, in reality, information devices having various transmission processing capabilities are mixed. Therefore, when a data transmission system is formed by arbitrarily combining these devices, in order to match the transmission speed among all the devices, the communication speed is determined according to the device with the lowest transmission processing.

For example, considering the case of data transmission between personal computers, the transmission processing capability of the personal computers is determined by the hardware processing capability such as the CPU performance and the amount of memory and the load of software running at the same time. If the processing capability of the hardware is low or the load of the software is heavy, the transmission processing capability of the personal computer is low, and it is necessary to set the transmission speed low. On the other hand, when the processing capacity of the hardware is high and the load of the software is small, the transmission speed of the personal computer can be set high.

When personal computers having different transmission processing capacities are connected to each other, data transmission is possible in all combinations, so that the transmission speed is set according to the personal computer having the lowest transmission processing capacity, that is, the slowest transmission speed. Must be done.

FIG. 23 is a schematic block diagram of a conventional start-stop data transmission device.

In FIG. 23, the transmitting side data transmission device 3
0 transmits the information in the memory 32 from the transmitter / receiver 33 to the receiving side data transmission device 35 via the transmission path 34 by the operation of the CPU 31.

On the other hand, the reception side data transmission device 35 stores the data received by the transmission / reception device 36 in the memory 38 by the operation of the CPU 37 or directly from the transmission / reception device 36.

In such a transmission / reception system, the data transmission rates of all the data transmission devices 30 and 35 are set in advance according to the device having the lowest transmission processing capacity.

Further, in the transmission / reception system, there may be a case where a method of transmitting a confirmation character before transmitting the data main body in the data transmission.

That is, the two data transmission devices 30,
Between 35, the transmission speed on the transmitting side is fixed, and the character "U"(55H; 55H here is a code representing "U" in hexadecimal) shown in FIG. 24 is transmitted as a confirmation character.

FIG. 25 is a sequence diagram showing the confirmation operation at this time.

In FIG. 25, first, the character "U" is transmitted from the transmission side data transmission device 30. If the character “U” can be confirmed on the receiving side data transmission device 35,
The reception confirmation signal is returned to the transmission side data transmission device 30, and the transmission side data transmission device 30 starts transmission of the data body.

If the character "U" cannot be confirmed on the receiving side data transmitting apparatus 35 side, the receiving side data transmitting apparatus 35 changes the receiving speed.

On the other hand, on the transmitting side, when a certain period of time has passed and a timeout occurs, the character "U" is transmitted again at the same transmission rate as before.

Then, if the character "U" can be confirmed on the receiving side, the transmission of the data body is started as described above.

When the character "U" cannot be confirmed on the receiving side even after the second transmission of the character "U", the character "U" transmission and the change of the receiving speed are repeated until it is confirmed.

[0018]

In the conventional method, it is necessary to set the transmission rate between the transmission apparatuses to the one having the lowest transmission rate among all the data transmission apparatuses.

Therefore, even in the data transmission between the devices having the higher transmission speed, the data is transmitted at the lowest transmission speed, and there is a problem that the capability of each transmission device is not utilized. It was

On the other hand, even when the method of transmitting the character "U" and adjusting the transmission rate is used, the confirmation communication takes time because the transmission must be repeated until the transmission rates match. There is a problem.

Further, as shown in FIG. 26, when the transmission speed of the transmission side is higher than that of the reception side, the received bit may be erroneously recognized, and correct communication may not be executed in some cases.

The present invention has been made in consideration of such a situation, and when performing data transmission without previously fixing the data transmission rate of the transmission system, the data transmission rate of the receiving side at the receiving side And a method of determining the start-stop data transmission that enables the transmission / reception side to determine each other's data transmission rate when performing data transmission without previously fixing the transmission system data transmission rate. It is an object of the present invention to provide a start-stop data transmission method that makes it possible to match each data transmission speed.

[0023]

In order to solve the above-mentioned problems, the invention according to claim 1 is a start-stop data transmission method for transmitting data between data transmission devices by start-stop transmission, wherein the data transmission device on the transmission side is From the transmission side, the data transmission device on the receiving side receives the transmission rate determination data, and the receiving side acquires the reception status information such as the identified reception data for the transmission rate determination data, and the transmitting side The data transmission rate of the transmission side is determined based on the reception state information determined by the relationship between the data transmission rate set in step 1 and the data transmission rate set on the reception side, and the reception state information acquired. This is a start-stop data transmission method.

The invention according to claim 2 is, in the invention according to claim 1, a type of error that occurs when the acquired reception state information receives the identified reception data or transmission rate determination data. This is a start-stop data transmission method that is data.

Further, in the invention according to claim 3, in the start-stop data transmission method for transmitting data between data transmission devices by start-stop transmission, the transmission speed judgment data is transmitted from the data transmission device on the transmission side, and the transmission speed judgment data is transmitted on the reception side. The data transmission device receives the transmission speed judgment data, and the receiving side acquires the reception status information such as the identified reception data of the transmission speed judgment data or the error type data generated by receiving the transmission speed judgment data. , The data transmission rate of the transmission side is determined based on the reception state information and the acquired reception state information determined by the relationship between the data transmission rate set on the transmission side and the data transmission rate set on the reception side, Based on this judgment result, the data transmission rate on the receiving side is changed, and the data transmission device on the receiving side is changed at this changed data transmission rate. The response data is returned to the data transmission device on the receiving side, and on the transmitting side, the response receiving state information such as the identified response receiving data for the response data or the error type data generated by receiving the response data is acquired, Based on the reception status information and the acquired response reception status information determined by the relationship between the data transmission rate set on the transmission side and the data transmission rate set on the reception side,
This is a start-stop data transmission method in which the data transmission rate of the receiving side is determined and the data transmission rate of the transmitting side is matched with the data transmission rate of the receiving side based on the result of this determination.

Furthermore, the invention corresponding to claim 4 is as follows.
In the inventions corresponding to claims 1 to 3, the transmission speed determination data is a start-stop data transmission method in which the transmission side data transmission device is added to the head of the transmission data body to be transmitted.

On the other hand, the invention according to claim 5 is the start-stop data transmission method according to the inventions according to claims 1 to 4, wherein the transmission speed judgment data is 1 byte data of "F8" in hexadecimal notation. is there.

The invention according to claim 6 is the start-stop data transmission method according to the inventions according to claims 1 to 4, wherein the transmission speed determination data is 1-byte data of "80" in hexadecimal notation. is there.

Further, the invention according to claim 7 is the start-stop data transmission method according to the inventions according to claims 1 to 4, wherein the transmission speed judgment data is 1-byte data of "FF" in hexadecimal notation. is there.

Furthermore, the invention corresponding to claim 8 is
In the inventions corresponding to claims 1 to 4, the transmission speed judgment data is 1 byte data of "FF" in hexadecimal notation and 1
This is a start-stop type data transmission method which is a total of 2 bytes of data consisting of 1 byte of "80" in hexadecimal notation.

On the other hand, the invention according to claim 9 is a hexadecimal number as the determination data for determining the data transmission rate of the transmitting side in the start-stop data transmission method of transmitting data between data transmission devices by start transmission. In display
The leading transmission rate judgment data and the trailing end transmission rate judgment data, which are 1-byte data of "00", are added after the fixed length transmission data body, and the fixed length transmission data including each transmission judgment data is transmitted to the sender side data. The transmission data is transmitted from the transmission device, the transmission data is received by the data transmission device on the reception side, and the reception side determines whether or not the data transmission rate on the transmission / reception side matches based on the reception state information about the leading transmission rate determination data. If the data transmission rates do not match, the reception side measures the time between the leading transmission rate determination data and the trailing end transmission rate determination data to determine the data transmission rate of the transmitting side. Is.

[0032]

Therefore, first, in the start-stop data transmission method according to the first aspect of the present invention, start-stop or synchronous data transmission is performed.

First, the transmission speed determination data is transmitted from the transmission side of the data transmission device. At this time, the transmission rate determination data may be added to the transmission data to be originally transmitted, or only the transmission rate determination data may be transmitted, for example.

Next, the transmission speed judgment data is received at the receiving side of the data transmission device.

Then, the receiving side obtains the reception status information such as the identified reception data of the transmission rate determination data.

Here, since the data transmission rates of the transmitting and receiving sides are not always the same, the information acquired at the receiving side is
It is not always the same as the transmission rate judgment data output by the transmitting side. In other words, since the transmission rate judgment data is read based on the data reception rate of the receiving side, if the data transmission rate of the transmitting / receiving side is different, the receiving side will receive the data different from the data output by the transmitting side. Will be recognized as.

However, the reception status information such as the identified reception data corresponds to the relationship between the setting transmission rate on the transmitting side and the setting transmission rate on the receiving side if the content of the transmission rate determination data is determined in advance. Will be fixed.

Therefore, the data transmission rate on the transmission side can be determined on the basis of these relations and the received reception state information.

Therefore, it is possible to take measures such as changing the transmission rate of the receiving side from the determined data transmission rate of the transmitting side.

Further, in the start-stop data transmission method of the invention according to claim 2, the same operation as that of the invention according to claim 1 is achieved, and not only the above-identified received data is used as the reception status information, Since the error type data generated by receiving the transmission rate determination data is also used, it is possible to more reliably determine the data transmission rate of the transmitting side in a wide range.

Here, as the above error, for example, a framing error, a break character detect (break error), etc. can be considered.

Further, in the start-stop data transmission method of the invention according to claim 3, first, similarly to the invention according to claim 2, the receiving side first determines the data transmission rate of the transmitting side.

Next, based on this determination result, the data transmission rate on the receiving side is changed.

At this time, the rate change may be made to, for example, the transmission side data transmission rate. If the reception side cannot realize the transmission side data transmission rate, for example, it may be set to the maximum data transmission rate that can be set at the reception side. .

Further, with this changed data transmission rate,
Response data is returned from the reception side to the data transmission device on the transmission side. This response data corresponds to the transmission rate judgment data from the transmitting side.

Therefore, the transmission side can determine the data transmission rate of the reception side based on the response reception state information from the response data, as in the case of the reception side.

Then, on the transmitting side, it becomes possible to match the data transmission rate on the transmitting side with the data transmission rate on the receiving side, based on the result of this judgment.

Therefore, it is not necessary to match the entire transmission system to the data transmission device having the slowest transmission speed in the transmission system, and the transmission speed can be changed according to the capability of each transmission device, and the efficiency of each device can be improved. Operation becomes possible.

Furthermore, in the start-stop data transmission method of the invention according to claim 4, the same operation as that of the invention according to claims 1 to 3 is carried out, and the transmission speed judgment data is the transmission side data transmission device. Since it is added to the beginning of the transmission data body to be transmitted, if the data transmission rates of both the transmitting and receiving sides match from the beginning, the transmission rate confirmation and data transmission will be performed at the same time, which is efficient. is there.

On the other hand, in the start-stop data transmission method of the invention according to claim 5, the same operation as that of the invention according to claims 1 to 4 is performed, and "F8" in hexadecimal notation is displayed in the transmission speed determination data. 1 byte data is used.

Further, in the start-stop data transmission method of the invention according to claim 6, the same operation as that of the invention according to claims 1 to 4 is performed, and in addition, "80" in hexadecimal notation is displayed in the transmission speed determination data. 1 byte data is used.

Further, in the start-stop data transmission method of the invention according to claim 7, the same operation as the invention according to claims 1 to 4 is performed, and in addition, "FF" in hexadecimal notation is displayed in the transmission speed determination data. 1 byte data is used.

Furthermore, in the start-stop data transmission method of the invention according to claim 8, the same operation as that of the invention according to claims 1 to 4 is performed, and in addition to the transmission rate determination data, 1
A total of 2 bytes of data consisting of 1-byte data of "FF" in hexadecimal notation and 1-byte data of "80" in hexadecimal notation are used.

On the other hand, in the start-stop data transmission method of the invention corresponding to claim 9, the determination data for determining the data transmission rate on the transmission side is 1-byte data of "00" in hexadecimal notation. The leading transmission rate determination data and the trailing transmission rate determination data are added after the fixed-length transmission data body.

Next, fixed length transmission data including each transmission determination data is transmitted from the transmission side data transmission device, and the transmission data is received by the reception side data transmission device.

Then, on the receiving side, it can be determined that the data transmission rates on the transmitting and receiving sides are the same unless the reception status information on the leading transmission rate determination data is error.

Therefore, the transmission side transmission rate may be checked only when the data transmission rates of both sides do not match.

Specifically, since the transmission data has a fixed length, the data transmission rate of the transmission side can be determined by measuring the time between the leading transmission rate determination data and the rear end transmission rate determination data at the receiving side. You can

[0059]

Embodiments of the present invention will be described below.

(First Embodiment) In the start-stop data transmission method of the present embodiment, first, 1
It is necessary to transmit the transmission speed judgment data in bytes, judge the transmission speed from the reception status of the transmission speed judgment data, set the reception speed (transmission speed), and send the judgment result back to the sender. For example, the transmission rate (transmission rate) on the transmission side is to be reset.

FIG. 1 is a block diagram showing an example of a data transmission system using the start-stop data transmission method according to the first embodiment of the present invention.

In FIG. 1, a data transmission system of this embodiment, which is a kind of network system, is a personal computer,
It is composed of a transmission side data transmission device 1 and a reception side data transmission device 2 which are workstations and other information devices, and a transmission line 3 connecting them.

The data transmission device 1 on the transmission side performs a series of data transmission operations and controls the data transmission device 1 on the transmission side C.
PU4, various data including transmission data, and program memory 5 and determination table 6 for a series of data transmission operations
A memory 7 for storing the data, a transmission / reception unit 8 for transmitting / receiving start-stop data to / from the reception-side data transmission device 2 via the transmission path 3, and other peripheral elements (not shown).

Here, in the program memory 5, the transmission rate determination data transmitting section 5 for transmitting the transmission rate determination data is provided.
a, a response data recognition unit 5b, a determination unit 5c, a transmission speed setting unit 5d, and a data transmission unit 5e are provided. Further, the determination table 6 is used for the receiving side data transmission device 2
It is for determining the response data returned from the.

On the other hand, the reception side data transmission device 2 includes a CPU 9 for controlling a series of data transmission operations and other control of the reception side data transmission device 2, a program memory 10 and a judgment table 11 for various data and a series of data transmission operations. A memory 12 for storing and a transmitter / receiver unit 1 for performing start / stop data transmission / reception with respect to a transmission side data transmission apparatus 1 via a transmission line 3.
3 and other peripheral elements (not shown).

Here, in the program memory 10, a transmission rate determination data recognition section 10a, a determination section 10b for determining transmission rate determination data, a response section 10c for returning a determination result, and a transmission rate setting section 10d. Is provided.

Further, the judgment table 11 is for judging the transmitted transmission speed judgment data.

In FIG. 1, for convenience of description, the data transmission device 1 on the transmission side and the data transmission device 2 on the reception side are separated, but each of the data transmission devices 1 and 2 is on both the transmission side and the reception side. It is possible to function as either the transmitting or receiving side.

Although only two data transmission devices are shown in FIG. 1, a large number of data transmission devices are actually connected as needed.

Next, a start-stop data transmission method in the data transmission system of the present embodiment having the above configuration will be described.

In this embodiment, as shown in FIG.
F8H (hexadecimal number display, the same applies hereinafter) is transmitted as 1-byte transmission speed determination data.

In start-stop data transmission, as shown in FIG. 2, a start bit ST and a stop bit S
It is synchronized by P. Furthermore, at the receiving side
Only bytes are treated as valid. At this time, if the transmission speed and the reception speed are different, if at least the first synchronization can be achieved by the start bit ST, the received transmission speed determination data is converted into 1-byte data different from the transmitted transmission speed determination data. Be recognized. If it cannot be recognized as 1-byte data, a certain error will occur.

Here, F8H is used as the transmission control determination data.
3 is used, the error such as 1-byte data or framing error, break character detect (also called break error), etc., which is recognized by the receiving side with respect to the transmitting side transmitting speed and the receiving side transmitting speed is shown in FIG. The relationship as shown is established. This table is stored in the determination table 11. A similar table is also stored in the judgment table 6.

The 1-byte data or the error that has occurred is an example of reception status information or response reception status information.

Such a determination table is prepared in advance, and 1
By transmitting / receiving the transmission control determination data in which the number of bytes is determined, the transmission speed of the transmitting / receiving side can be adjusted.

FIG. 4 is a sequence diagram showing an example of a series of data transmission operations in this embodiment.

First, the transmission rate determination data F8 is transmitted from the transmission side data transmission apparatus 1 to the transmission rate determination data transmission section 5a.
H is transmitted.

Next, when receiving the transmission rate determination data, the receiving side data transmission apparatus 2 performs a series of operations such as recognition of the received data, determination, and transmission speed change according to the flow shown in the flow chart of FIG. .

FIG. 5 is a flow chart showing the transmission rate judgment change processing in the receiving side data transmission apparatus of this embodiment.

First, when the transmission rate determination data is received (ST1), the transmission rate determination data recognition section 10a
Receiving data is sampled for recognition (ST
2).

The received data recognized next is determined by the determination unit 10
It is judged using the judgment table 11 by b (ST
3). Here, if the received data is F8H (ST
3) The transmission rates set on the transmitting side and the receiving side are the same. Therefore, the response unit 10c responds as it is to F8H as response data (ST5).

On the other hand, if the recognized received data is not F8H, the transmission rates set on the transmitting side and the receiving side are different (ST3).

Here, the recognition of received data when the transmission rate setting is different between the transmitting side and the receiving side will be described with reference to FIG.

FIG. 6A shows a transmission side transmission rate 1200b.
This is a case where the ps setting and the receiving side transmission speed of 2400 bps are set. Here, since the transmission speed on the receiving side is twice that on the transmitting side, the data transmitted as F8H from the transmitting side is recognized as 80H on the receiving side as shown in the figure.

Further, FIG. 6B shows the transmitting side 4800 bp.
In the case of s, the receiving side is 1200 bps. In this case, the transmission rate on the receiving side is ¼ of that on the transmitting side, so that it is recognized as FFH on the receiving side as shown in the figure.

Therefore, the recognized received data is F8.
When it is not H, the transmission rate setting unit 10d changes the transmission rate of the reception side data transmission apparatus 2 to the corresponding transmission rate of the transmission side based on the determination table 11. If the receiving side data transmission apparatus 2 cannot reach the corresponding transmission side transmission rate, the maximum data transmission rate of the data transmission apparatus 2 is set (ST4).

Then, the response section 10c transmits F8H as the response data to the transmission side data transmission apparatus 1 (S
T5).

When the response data is transmitted, it is received by the transmitting side in the sequence diagram shown in FIG. On the transmission side, based on the received data of the response data, the data recognition and the same recognition and judgment as the transmission speed judgment described in FIG.
c.

Here, when there is still a difference between the transmission rates of the transmitting side and the receiving side, the transmission rate of the receiving side data transmission apparatus 2 is increased to the data transmission rate which is first sent by the transmitting side data transmission apparatus 1. This is the case when it is not possible.

Therefore, when the response data is checked and the recognized data is not F8H, the transmission rate setting section 5d on the transmitting side changes the transmission rate based on the contents of the determination table, and the receiving side data transmitting apparatus 2 Match the transmission speed of. Since the transmission speeds on the transmission and reception sides are completely matched by this speed adjustment, here, step S in FIG.
No response output corresponding to T5 is performed.

After checking the response data and changing the transmission rate if necessary, as shown in FIG.
The transmission of the data body to be transmitted from the transmission side, the confirmation response from the reception side, the transmission of the end data from the transmission side, and the transmission of the end confirmation from the reception side are performed, and the series of data transmission ends.

As described above, in the start-stop data transmission method according to the present embodiment, 1-byte “F8H” is transmitted from the transmission-side data transmission device 1 as the transmission speed determination data, and the reception data recognized by the reception side is transmitted. Since the determination table 11 determines the data transmission rate of the transmission side, the reception side can take necessary measures according to the data transmission rate of the transmission side without fixing the data transmission rate of the transmission system in advance. You can

Further, as described above, in the start-stop data transmission method according to the present embodiment, it is possible to include the error type data in the recognized received data, which can also be included in the judgment tables 6 and 11. The data transmission rate can be determined in a wide range.

Further, as described above, in the start-stop data transmission method according to the present embodiment, the transmission speed on the receiving side is matched with the transmission speed on the determined transmission side, or when the transmission rate on the receiving side cannot be adjusted, the transmission rate on the receiving side is changed. Response data is sent back to the transmitting side according to the maximum transmission rate, the transmitting side determines the transmission rate of the receiving side by the same procedure, and the transmission rates of the data transmission devices 1 and 2 on the transmitting and receiving sides are made to match. It is possible to adjust each data transmission rate in a short time when performing data transmission without previously fixing the transmission rate of the data of the transmission system.

Therefore, in a data transmission system in which the level of the processing capacity differs depending on the transmission apparatus, the communication between the high processing capacity apparatuses is high speed, and the communication between the high processing capacity apparatus and the low processing capacity apparatus is the maximum of the low processing capacity apparatus side. Transmission can be performed at a transmission rate, and efficient operation of each device can be achieved.

(Second Embodiment) In the start-stop type data transmission method of the present embodiment, the transmission rate judgment data and the main body of the transmission data are continuously transmitted.

FIG. 7A shows the structure of the transmission data frame at this time, and FIGS. 7B and 7C show sequence diagrams. The configuration of the data transmission system using the start-stop data transmission method of the present embodiment is the same as that of the system of the first embodiment, so detailed description will be omitted.

In FIG. 7A, the transmission data frame is formed by adding the transmission speed judgment data fa to the beginning of the transmission data frame fb which is the main body of the data to be transmitted.

Next, a series of data transmission operations in this embodiment will be described with reference to the sequence diagrams of FIGS. 7B and 7C and the flow chart of FIG.

First, in FIG. 8, when the receiving side receives the transmission data frame (ST11), the leading 1-byte data is recognized (ST12), and it is determined whether it is F8H based on the determination table 11 ((8)). ST1
3).

If the received data is F8H, that is, if the transmission rates on the transmitting and receiving sides are the same (ST13), the transmission data is fetched as it is, and further the transmission rate determination data fa
The transmission data frame added with is transmitted as response data (ST14).

In this case, in FIG. 7B, when the transmission side receives the transmission data frame as the response data, it can confirm that the transmission data frame transmitted first is normally delivered. After that, the transmitting side sends the end data, the receiving side sends back an end confirmation for the end data, and the series of data transmission operation ends.

On the other hand, in FIG. 8, if the reception data recognized in step ST13 is not F8H, the reception side data transmission device 2 obtains the transmission side transmission rate from the determination table 11 (ST15).

Next, it is judged whether or not this transmission rate exceeds the maximum transmission rate in the receiving side data transmission device 2 (ST16). If not, the transmission rate is adjusted to the transmitting side (ST17), and it is exceeded. If so, the maximum transmission rate on the receiving side is set (ST18).

In each case, 1 is set as the response data.
Only the byte F8H is returned to the transmitting side (ST19).

In this case, in FIG. 7 (c), the transmitting side uses F8 as the 1-byte received data as the response data.
When H is received, the receiving side determines that the transmission rate is the same as that of the transmitting side, and again transmits the transmission data frame.

On the other hand, if the first byte of the response data is not F8H, it is determined that the transmission was not normally performed, and that the receiving side could not match the same transmission speed as the transmitting side.
At this time, the transmission rate of the receiving side is determined from the recognized reception data and the determination table 6, and the transmission data frame is sent again according to the transmission rate of the transmitting side to the receiving side.

Thereafter, as in the case of FIG. 7B, the receiving side returns the transmission data frame, the transmitting side sends the end data, the receiving side returns the end confirmation for the end data, and a series of data. The transmission operation ends.

As described above, in the start-stop data transmission method according to the present embodiment, the transmission speed judgment data is added to the head of the transmission data body, and if the data transmission is possible, the data is transmitted as it is, and it is transmitted only when the data transmission is not possible. Since the response data is sent back to the side, the same effect as the above embodiment can be obtained, and if the data transmission rates of both the transmitting and receiving sides match from the beginning, the transmission rate is confirmed and the data transmission is performed at the same time. It will be efficient.

(Third Embodiment) In the start-stop data transmission method according to the present embodiment, the determination tables 6 and 11 shown in FIG. 1 are shown in FIG. 9 in which the transmission rate can be determined even if the transmission rate is 9600 bps or more. The judgment table shown in is added.

Here, the configuration of the data transmission system and the series of data transmission operations are the same as those shown in FIGS. 1 and 4, respectively.

FIG. 10 is a flow chart of the determination / speed change processing in this embodiment.

In FIG. 10, first, the transmission rate judgment data is received (ST21), and this is sampled (ST22) to make the judgment. If the range of the transmission rate does not exceed the range of the determination table shown in FIG. 3 (ST23), the determination table of FIG. 3 is used (ST2).
4) Perform processing from step ST3 in FIG. 5 (ST2
7).

On the other hand, if the range of the transmission rate exceeds the range of the determination table shown in FIG. 3 (ST23), the receiving side switches the transmission rate to 9600 bps or more and waits without sending a response (ST25).

When the transmitting side does not receive a response, the transmission rate judgment data is retransmitted to the receiving side. Therefore, when the receiving side receives the retransmitted transmission rate judgment data (ST26), it changes the transmission rate according to the table of FIG. 9 and sends a response (ST27).

As described above, in the start-stop data transmission method according to this embodiment, if the received data cannot be determined,
Since the transmission rate is determined differently by retransmitting the transmission rate, it is possible to obtain the same effect as that of the above-described embodiment, and even if the difference in the transmission rate between the data transmission devices is large, The setting can be changed reliably.

The method of this embodiment can be applied not only to the first embodiment but also to the second embodiment.

(Fourth Embodiment) In the start-stop data transmission method according to the present embodiment, the transmission speed judgment data is shown in FIG.
As shown in FIG. 12, the determination table shown in FIG. 12 is stored as the determination tables 6 and 11 in FIG.

Here, the configuration of the data transmission system and the series of data transmission operations are the same as those shown in FIGS. 1 and 4, respectively.

Further, the transmission rate (reception rate) for receiving data in the receiving side data transmission apparatus is fixed at 4800 bps, and the transmission rate judgment data (80
H) is transmitted.

FIG. 13 is a flow chart of the determination / speed change processing in this embodiment.

First, when the transmission rate judgment data is received (ST31), the received data is sampled and judged (ST32).

If the recognized received data is 80H (ST33), 80H is returned as response data (ST3).
5) If the recognized received data is not 80H (ST
33), the transmission rate is changed according to the determination table of FIG. 12 (ST34), and the response data is transmitted (ST35).

At this time, if the receiving side data transmission apparatus 2 cannot increase the transmission rate to the transmission rate at which the transmission rate judgment data is transmitted, the response data is transmitted at the maximum transmission rate of the receiving side data transmission apparatus 2. (ST35).

Hereinafter, as in the case of the first embodiment, the transmission speed is changed according to the response data, that is, if necessary, the transmission rate is changed by the determination table of FIG.
Data transmission is performed.

As described above, in the start-stop data transmission method according to the present embodiment, the transmission speed judgment data is 1 byte 80 bytes.
Since it is set to H and the initial transmission rate on the receiving side is fixed, the same effect as the above embodiment can be obtained, and the transmission rate determination / change from a device having a high transmission speed to a device having a slow transmission speed can be performed reliably and in a wide range. be able to.

The method of this embodiment can also be applied to the second embodiment.

(Fifth Embodiment) In the start-stop data transmission method according to the present embodiment, the transmission speed judgment data is shown in FIG.
15 is stored as the determination tables 6 and 11 in FIG. 1.

Here, the configuration of the data transmission system and the series of data transmission operations are the same as those shown in FIGS. 1 and 4, respectively.

The transmission rate (reception rate) for receiving data in the receiving side data transmission apparatus is 38400 bps.
The transmission rate judgment data (FF
H) is transmitted.

FIG. 16 is a flow chart of the judgment / speed change processing in this embodiment.

In FIG. 16, steps ST41, 4
2, 45 denote steps ST31, 32,
The same as 35. Also, in step ST43,
The determination of the transmission rate determination data is performed based on FFH. Further, in step ST44, the determination table 11 shown in FIG. 15 is used. Other operations are the same as those in steps ST33 and ST34 in FIG. 13, and therefore the description thereof will be omitted.

In the following, as in the case of the first embodiment, the transmission data corresponding to the response data, that is, if necessary, the transmission rate is changed by the determination table of FIG.
Data transmission is performed.

As described above, in the start-stop data transmission method according to this embodiment, the transmission speed determination data is 1 byte FF.
Since the initial transmission rate on the receiving side is fixed to H, the same effect as that of the above-described embodiment can be obtained, and the data transmission device 1,
It is possible to judge and change a wide range of transmission rates between the two.

The method of this embodiment can be applied to the second embodiment, and the transmission rate judgment data can be added to the transmission data frame and transmitted.

(Sixth Embodiment) In the start-stop data transmission method according to the present embodiment, the transmission rate judgment data is shown in FIG.
2 bytes of data (FFH, 80H) as shown in FIG. At this time, the stop bit after FFH is 1 bit.

Further, the judgment tables 6 and 11 in FIG.
As a result, the determination table shown in FIG. 18 is stored.

Here, the configuration of the data transmission system and the series of data transmission operations are the same as those shown in FIGS. 1 and 4, respectively.

Further, the transmission rate (reception rate) for receiving data in the receiving side data transmission apparatus is 38400 bps.
The transmission rate judgment data (FF
H, 80H).

FIG. 19 is a flow chart of the determination / speed change processing in this embodiment.

In FIG. 19, steps ST51, ST5
2, 56 are steps ST31, 32,
The same as 35.

In step ST53, the first bit of the recognized received data is the start bit ST.
If it can be determined that the transmission rate is changed on the receiving side according to the determination table of FIG. 18 (ST55), the response data is transmitted (ST56).

In step ST53, especially when the transmission rate on the transmitting side is 76800 bps, the bits cannot be normally recognized as shown in FIG. 20 (a). However, since the bit determination is performed at the beginning and the middle of the bit, even if the beginning and the end of the bit are different from each other, the bit in FIG.
As shown in (b), if the start and middle of the bit are at the same level, the bit is recognized, so the start bit ST may be recognized.

If the start bit is not recognized (ST53), the data is read from the bit that can be recognized as the start bit ST (ST54), the transmission rate is changed according to the determination table of FIG. 18 (ST55),
Response data is transmitted (ST56).

When the device that has transmitted the transmission rate determination data receives the response data, if the transmission rate is the data transmission rate from the determination table of FIG. 18, the transmission rate at which the reception is performed is changed to the transmission rate when the transmission rate is transmitted. If set, and if they are different, the transmission rate is changed to the transmission data of the device that transmitted the response data according to the determination table of FIG. 18 for both transmission and reception.

As described above, in the start-stop data transmission method according to the present embodiment, the transmission speed determination data is 2 bytes (FFH, 80H) and the initial transmission speed on the receiving side is fixed. In addition to the same effect, it is possible to determine and change a wide range of transmission rates between the data transmission devices 1 and 2.

The method of this embodiment can be applied to the second embodiment.

(Seventh Embodiment) In the start-stop data transmission method according to the present embodiment, the transmission data frame has a fixed length as shown in FIG. 21 (a), and is placed before and after the fixed-length transmission data body fb. 0 as the transmission speed judgment data fa and fc
0H is added and transmission is performed from the transmitting side.

Further, in the judgment table 11 in FIG. 1, the transmission speed judgment data f before and after the transmission data body fb are stored.
When a and fc (00H) are correctly recognized, it is determined that the transmission speeds of the transmitting and receiving sides are the same, and when a framing error or break character detect (the same as the break error) occurs, the transmitting speed of the transmitting and receiving sides is A determination table that can determine that the speeds are not the same is stored.

Here, in the structure of the data transmission system,
Each of those shown in FIG. 1 is provided with a time measuring means from the reception start of the transmission data frame to the reception end, and a transmission rate calculating means for calculating the transmission rate of the transmission side from the time measurement result (not shown). ).

Further, the transmission side data transmission apparatus 1 is adapted to retransmit the transmission data frame when the response data is not returned even after the lapse of a fixed time.

Next, a series of data transmission operations in this embodiment will be described with reference to the sequence diagrams of FIGS. 21 (b) and 21 (c) and the flow chart of FIG.

In FIGS. 21B and 21C, first, a transmission data frame is transmitted from the transmitting side.

In FIG. 22, when the receiving side receives the transmission data frame (ST61), the receiving side determines whether or not the first transmission rate determination data fa (00H) can be recognized (S60).
If it can be recognized, it is determined whether or not a framing error or break character detect occurs, that is, whether or not the transmission rate determination data fa can be determined to be 00H (ST63).

If no framing error or break character detect occurs, the receiving side sends the response data to the transmitting side (ST64). That is,
This is a case where the transmission speeds of the transmitting and receiving sides are the same and normal communication is possible.

In this case, in FIG. 21B, the transmitting side continues the communication when receiving the response data, and when all the data transmission is completed, the above procedure is carried out to end the communication.

On the other hand, in FIG. 22, step ST62.
If the first transmission rate determination data fa (00H) cannot be recognized in step S4, or if a framing error or break character detect occurs in step ST63,
The time until the reception of the sent data is completed is measured (ST65).

Then, the transmission rate of the transmission side data transmission apparatus 1 is calculated from the measured time, and the transmission rate of the reception side is changed (ST66).

Further, no response is sent to the transmitting side data transmitting apparatus 1 (ST67).

In this case, in FIG. 21 (c), the transmission side considers that the data transmission is not normally performed when the response data is not returned even after the lapse of a fixed time and the retransmission time is reached, and the transmission is performed. Retransmit the data frame. At this time, since the data transmission speed is adjusted on the receiving side, the same process as in the case of FIG.

The reason why 00H is used as the transmission rate judgment data fa and fc is that the reception rate is 1 rather than the transmission rate.
This is because it is possible to correctly convey the existence of the beginning and the end even if the level is lowered to / 8.

As described above, in the start-stop data transmission method according to this embodiment, the transmission data frame has a fixed length,
00H is added as the transmission rate judgment data fa and fc before and after the fixed length transmission data body fb, and when an error occurs on the receiving side, the time of the receiving data is measured and the transmission rate of the transmitting side is calculated from the measured time. Since the reception side transmission speed is adjusted, the same effect as the above embodiment can be obtained, and the transmission speed between data transmission devices can be determined / changed, and if the transmission speed is matched, It can be transmitted as is.

The present invention is not limited to the above embodiments, but can be variously modified without departing from the scope of the invention.

[0164]

As described above in detail, according to the present invention, the data transmission rate of the transmission side can be determined by the reception side when performing data transmission without fixing the transmission rate of the data of the transmission system in advance. To provide a start-stop data transmission method,
When data transmission is performed without fixing the data transmission rate of the transmission system in advance, both sides determine the data transmission rate of each other and do not set the transmission rate between the data transmission devices in advance. It is possible to provide a start-stop data transmission method capable of transmitting data at an appropriate transmission rate.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an example of a data transmission system using a start-stop data transmission method according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of transmission rate determination data used in the start-stop type data transmission method of the first embodiment.

FIG. 3 is a diagram showing an example of a determination table in the data transmission system used in the first embodiment.

FIG. 4 is a sequence diagram showing an example of a series of data transmission operations in the first embodiment.

FIG. 5 is a flowchart showing the operation of the data transmission device in the first embodiment.

FIG. 6 is an explanatory diagram for recognizing received data when the transmission rate setting is different between the transmitting side and the receiving side in the embodiment according to the present invention.

FIG. 7 is a diagram showing an example of a transmission data frame of a second embodiment according to the present invention and a sequence diagram showing an example of a series of data transmission operations.

FIG. 8 is a flowchart showing the operation of the data transmission device according to the second embodiment.

FIG. 9 is a diagram showing an example of a determination table in the data transmission system used in the third embodiment of the present invention.

FIG. 10 is a flowchart showing the operation of the data transmission device according to the third embodiment.

FIG. 11 is a diagram showing an example of transmission rate determination data used in the start-stop data transmission method according to the fourth embodiment of the present invention.

FIG. 12 is a diagram showing an example of a determination table in the data transmission system used in the fourth embodiment.

FIG. 13 is a flowchart showing the operation of the data transmission device according to the fourth embodiment.

FIG. 14 is a diagram showing an example of transmission rate determination data used in a start-stop data transmission method according to a fifth embodiment of the present invention.

FIG. 15 is a diagram showing an example of a determination table in the data transmission system used in the fifth embodiment.

FIG. 16 is a flowchart showing the operation of the data transmission device according to the fifth embodiment.

FIG. 17 is a diagram showing an example of transmission rate determination data used in the start-stop data transmission method according to the sixth embodiment of the present invention.

FIG. 18 is a diagram showing an example of a determination table in the data transmission system used in the sixth embodiment.

FIG. 19 is a flowchart showing the operation of the data transmission device according to the sixth embodiment.

FIG. 20 is an explanatory diagram of start bit recognition of transmission rate determination data in the sixth embodiment.

FIG. 21 is a diagram showing an example of a transmission data frame according to a seventh embodiment of the present invention and a sequence diagram showing an example of a series of data transmission operations.

FIG. 22 is a flowchart showing the operation of the data transmission device according to the seventh embodiment.

FIG. 23 is a schematic configuration diagram of a conventional start-stop data transmission device.

FIG. 24 is a diagram showing a confirmation character in conventional data transmission.

FIG. 25 is a sequence diagram showing an example of a series of data transmission operations in the conventional method.

FIG. 26 is an explanatory diagram showing erroneous bit recognition of a confirmation character in the conventional method.

[Explanation of symbols]

1 ... Transmission side data transmission device, 2 ... Reception side data transmission device, 3 ... Transmission path, 6 ... Judgment table, 7 ... Memory, 8 ...
Transceiver, 11 ... Judgment table, 12 ... Memory, 13 ...
Transmitter / receiver, fa, fc ... Transmission rate judgment data, fb ... Transmission data main body, ST ... Start bit, SP ... Stop bit.

Claims (9)

[Claims] 1. A start-stop data transmission method for transmitting data between data transmission devices by start-stop transmission, wherein transmission rate determination data is transmitted from the data transmission device on the transmission side, and the transmission rate is transmitted on the data transmission device on the reception side. Receiving judgment data, the receiving side obtains reception status information such as identified reception data for the transmission speed judgment data, and the data transmission rate set by the transmitting side and the receiving side are set by the receiving side. Based on the reception status information and the acquired reception status information determined by the relationship with the data transmission rate,
A start-stop data transmission method, characterized in that the data transmission rate on the transmitting side is determined. 2. The start-stop method according to claim 1, wherein the acquired reception state information is type data of an error caused by receiving the identified reception data or the transmission rate determination data. Data transmission method. 3. A start-stop data transmission method for transmitting data between data transmission devices by start-stop transmission, wherein transmission speed determination data is transmitted from the data transmission device on the transmission side, and the transmission speed is transmitted on the data transmission device on the reception side. Receiving the determination data, and on the receiving side, the reception status information such as the identified reception data of the transmission rate determination data or the type data of the error caused by receiving the transmission rate determination data, and the like, On the basis of the reception status information and the acquired reception status information determined by the relationship between the data transmission speed set on the side and the data transmission speed set on the receiving side,
The data transmission rate of the transmission side is determined, the data transmission rate of the reception side is changed based on the determination result, and the data transmission rate of the reception side is changed from the data transmission apparatus of the reception side at the changed data transmission rate. Returning response data to the transmission device, and on the transmitting side, obtain response receiving state information such as identified response receiving data for the response data or error type data generated by receiving the response data, Based on the reception status information determined by the relationship between the data transmission rate set on the transmission side and the data transmission rate set on the reception side, and the acquired response reception state information, the data transmission rate on the reception side is set. A determination is made, and based on this determination result, the data transmission rate of the transmitting side is made to match the data transmission rate of the receiving side. Expression data transmission method. 4. The transmission rate determination data is added to the beginning of the transmission data body to be transmitted by the data transmission device on the transmission side, according to any one of claims 1 to 3. Start-stop data transmission method. 5. The start-stop data transmission method according to claim 1, wherein the transmission speed determination data is 1-byte data of “F8” in hexadecimal notation. 6. The start-stop data transmission method according to claim 1, wherein the transmission speed determination data is 1-byte data of “80” in hexadecimal notation. 7. The start-stop data transmission method according to claim 1, wherein the transmission speed determination data is 1-byte data of “FF” in hexadecimal notation. 8. The transmission speed judgment data is "FF" 1-byte data in hexadecimal notation and "8" in hexadecimal notation.
5. A total of 2 bytes of data consisting of 1 "data of 0", and any one of claims 1 to 4.
A start-up type data transmission method according to the item. 9. In the start-stop data transmission method for transmitting data between data transmission devices by start-stop transmission, 1-byte data of "00" in hexadecimal notation is used as determination data for determining the data transmission rate on the transmission side. The leading transmission rate judgment data and the trailing end transmission rate judgment data are added after the fixed-length transmission data body, and the fixed-length transmission data including each of the transmission determination data is transmitted from the transmission side data transmission device. Then, the data transmission device on the reception side receives the transmission data, and the reception side determines whether or not the data transmission rates of the transmission and reception sides match based on the reception state information about the leading transmission rate determination data. However, when the data transmission rates do not match, the reception side determines the start transmission rate determination data and the rear end transmission rate determination data. Start-stop data transmission method characterized by determining the data transmission rate of the sender by measuring the time over data.