JP2760015B2 - Programmable controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of the Invention> The present invention relates to an ID (automatic recognition) system that collects unique information about a work by performing non-contact communication with a data carrier attached to a moving work. The present invention relates to a programmable controller having an interface for use.

<< Summary of the Invention >> The present invention relates to a programmable controller having an ID system function, the number of retries of a call operation performed prior to data exchange with a data carrier attached to a work, and the number of retries performed for each data carrier. By displaying the maximum value of the number of retries so far, the communication state affected by disturbance or the like can be easily grasped.

<Prior art and its problems> Conventionally, in a programmable controller having an ID system function, since data exchange with a data carrier attached to a work is non-contact spatial communication, disturbance such as noise is mixed. Communication errors are easy to occur. Therefore, as shown in the flowchart of FIG.
Until normal communication is completed, each time a communication error occurs, the calling operation is repeated again, the number of times is counted as the number of retries, and the number of retries is the number set in the retry counter RC, for example, 10 times. Is reached, it is determined that a communication error has occurred, and an error signal is output.

However, as described above, if an error is output only when the set number of retries has been reached, the number of retries that can be established for data transfer communication for each work, that is, the disturbance of each work, There is a problem that it is not possible to know the degree of the effect.

<< Object of the Invention >> The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to achieve a retry count up to that point even when communication with a data carrier of an individual work is established. It is an object of the present invention to provide a programmable controller which can easily know the degree of disturbance influence by knowing the degree of disturbance.

<< Structure and Effect of the Invention >> In order to achieve the above object, the present invention provides an ID interface for transferring data in a non-contact manner with a data carrier attached to a moving work and storing information on the work, and a data transfer communication. Prior to the above, the storage means for storing the number of retries of a call operation performed until a valid response is made from the ID interface to the data carrier, and the predetermined number of retries for the same data carrier is completed. Error response means for stopping the calling operation and outputting an error when no response is obtained, storage updating means for storing and updating the maximum value of the number of retries for each data carrier, and storing in the storage updating means. Maximum retries,
And output means for outputting the number of retries for the data carrier during the calling operation.

With this configuration, in the programmable controller of the present invention, the number of retries of the call operation performed prior to the data transfer communication with the data carrier attached to the work, and the number of retries performed for each data carrier. By outputting the maximum value of the retry number of
It is possible to easily grasp the communication state affected by disturbance or the like.

<< Example >> Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows an ID system constituted by a programmable controller according to an embodiment.
It is configured by combining a CPU section 2, a power supply section 3, and the like.

The ID sensor unit 1 is connected to a read / write head 4 disposed on the movement path of the work 6 and a handy type computer 7 capable of inputting setting data of the number of retries and monitoring the counted number of retries. Have been.

When the data carrier 5 storing information on the work 6 reaches a predetermined position as the work 6 moves, the read / write head 4 starts reading data in the data carrier 5 by non-contact communication.

FIG. 2 is a block diagram showing an electrical configuration of the ID sensor unit 1.

The interface circuit 11 is connected to the CPU unit 2 of the main body via an I / O bus 21 and mediates data input / output of the shared memory 12 and the I / O circuit 13 for channel data with the main body.

The computer 7 connected to the connector 19 is directly connected to the CPU1.
Data input / output is controlled from 5.

Read / write head 4 connected to connector 10
Are connected to the CPU 15 via the R / W head communication interface 18.

The I / O circuit 14 performs SW input and display output to an LED.

In addition, the system memory 16, the work memory 17, the shared memory 12, the I / O circuit 13, and the like are connected to the CPU 15 and used to realize a function as an ID sensor unit.

Next, the operation of this embodiment will be described with reference to the flowchart of FIG.

First, when the operation of the system is started, the counter RC1 for counting the current value of the number of retries is cleared (step 3).
1).

Next, the work 6 reaches a predetermined position, and the read / write head 4 starts a calling operation to the data carrier 5 (step 32).

If a predetermined response is not obtained from the data carrier 5 within a predetermined time for the call, or if an error is detected after the communication is started, it is determined that an error has occurred (step 33N), and the counter RC1 is incremented. (Step 34).

When the incremented value of the counter RC1 is less than the set number 1 (step 35N), the process proceeds to step 32, and the calling operation is repeated.

Further, an error check is performed, and if communication is normally performed (step 33Y), the value of the counter RC1 at that time is stored in the memory R1 (step 37).

When the incremented value of the counter RC1 reaches the set number 10 (step 35Y), an error signal is output (step 36).

Here, the value of the counter RC1 that counts the current value of the number of retries is compared with the value of the counter RC2 that counts the maximum value of the number of retries for the work up to that point, and the value of RC1 exceeds the count value up to that point. If it has (Step 38N), the value of the counter RC1 is updated to the counter RC2, and the value is stored in the memory R2 (Step 39).

If the value of the counter RC1 is less than the value of the counter RC2 (step 38Y), the process ends as it is.

Here, the current value of the number of retries sequentially stored and updated in the memories R1 and R2 and the maximum value up to that time can be displayed on the display unit of the computer 7 by operating the key of the computer 7 at any time. The contents stored in the memories R1 and R2 can be cleared by key operation.

In this embodiment, during operation of the ID system,
Operation, the number of retries of communication between the read / write head 4 and the data carrier 5 can be confirmed. Therefore, even when a communication error frequently occurs at the time of system startup or due to some disturbance factor. Thus, the communication error occurrence status can be easily grasped, and the effect of appropriately taking the result of the disturbance countermeasure can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of an ID system using an embodiment of the present invention, FIG. 2 is a block diagram showing an electric configuration of a main part of FIG. 1, and FIG. FIG. 4 is a flowchart showing the operation of the conventional example. 1 ID sensor unit 2 CPU unit 3 Power supply unit 4 Read / write head 5 Data carrier 6 Work 7 Computer 10 Connector 11 Interface circuit 12 Shared memory 13 I / O circuit 14 I / O circuit 15 CPU 16 System memory 17 Work memory 18 R / W head communication interface 19 Connector 21 I / O bus

Claims (1)

(57) [Claims] An ID interface for transferring data in a non-contact manner with a data carrier which is attached to a moving work and stores information on the work. Prior to the data transfer communication, the ID interface transmits a valid data to the data carrier. Storage means for storing the number of retries of a call operation performed until a proper response is received, and stop the call operation when a response is not obtained even if the predetermined number of retries is completed for the same data carrier. And
Error output means for outputting an error, storage update means for storing and updating the maximum value of the number of retries for each data carrier, maximum number of retries stored in the storage update means, and the data carrier during the calling operation Output means for respectively outputting the number of retries for the programmable controller.