JP2016110458A5

JP2016110458A5 -

Info

Publication number: JP2016110458A5
Application number: JP2014248402A
Authority: JP
Filing date: 2014-12-08
Publication date: 2017-10-12
Anticipated expiration: 2034-12-08

Claims

A programmable logic controller having a basic unit that repeatedly executes a user program for each scan, and an expansion unit connected to the basic unit,
The expansion unit is
An interface to which an external device is connected;
A storage unit in which a device value related to an input value from the external device via the interface or an output value to the external device via the interface is stored, and a device for sharing data with the basic unit is allocated;
An expansion unit timer that counts the clock and measures time,
With
The basic unit is
A basic unit timer that counts the clock and measures time,
Synchronization means for synchronizing the timer values of the extension unit timer and the basic unit timer;
First update means for matching the data held by the extension unit and the data held by the basic unit within a refresh period for each scan;
Based on the timer value of the basic unit timer synchronized with the timer value of the extension unit timer by the synchronization means, the data held by the extension unit within the period of processing executed at regular intervals during scanning and the basic Second update means for matching the data held by the unit;
With
The programmable unit characterized in that the device of the extension unit described in the user program can be set as an update target by the first update means and / or an update target by the second update means. Logic controller.

2. The programmable logic controller according to claim 1, wherein the device is set as one of an update target by the first update unit and an update target by the second update unit.

2. The programmable logic controller according to claim 1, further comprising selection means for selecting at least one of the first update means and the second update means as update means for updating the device.

The basic unit includes a program storage unit that stores the user program and an inter-unit synchronization program executed based on a timer value of the basic unit timer synchronized by the synchronization unit,
The second update means matches the data held in the extension unit with the data held in the basic unit when the device is described in the inter-unit synchronization program. The programmable logic controller according to claim 1.

The second updating means matches the data held by the extension unit with the data held by the basic unit even during a period in which the user program is being executed during the scan. The programmable logic controller according to claim 1, wherein:

The timer value of the extension unit timer is used as a start timing of internal processing of the extension unit,
The internal processing of the extension unit is processing for calculating the device value based on an input value from the external device or processing for calculating an output value from the device value to the external device. The programmable logic controller according to any one of 1 to 5.

2. The first update means performs update within a refresh period for each scan based on a timer value of the basic unit timer synchronized with a timer value of the extension unit timer by the synchronization means. Programmable logic controller described in 1.

The basic unit and the extension unit each have a device that is a storage area for holding data,
The device includes an input device for transmitting data of the expansion unit to the basic unit, and an output device for transmitting data of the basic unit to the expansion unit;
The first update unit and the second update unit update a device value that is data of the input device by copying a device value that is data stored in the device of the expansion unit to the device of the basic unit. And updating a device value, which is data of the output device, by copying a device value, which is data stored in the device of the basic unit, to the device of the extension unit. 8. The programmable logic controller according to any one of 7 above.

The input device stores data representing a function state of the extension unit;
The programmable logic controller according to claim 8, wherein the output device stores data for controlling a function of the extension unit.

In the refresh period, the first updating means updates the data held in the output device and the data held in the input device, and is scanned at regular intervals during scanning based on the timer value of the basic unit timer. The programmable according to claim 8 or 9, wherein the second updating means updates data held in the extension unit and data held in the basic unit during a period of processing to be executed. -Logic controller.

The second update unit matches data between a device provided in the basic unit and holding data and a buffer memory provided in the extension unit and holding data not to be refreshed The programmable logic controller according to any one of claims 1 to 7, wherein the programmable logic controller is provided.

The selection means includes storage means for storing update target designation information for designating data to be updated by the second update means,
The second update means updates the data specified by the update target specification information,
4. The programmable logic controller according to claim 3, wherein the first update unit updates data that is not specified by the update target specification information during the refresh period. 5.

13. The extension unit according to claim 1, wherein the extension unit delays a start of an internal process executed by the extension unit according to a delay time of an update process in the second update unit. Programmable logic controller.

The programmable logic controller according to claim 1, wherein the extension unit holds the data in a storage device provided in the basic unit.

15. The extension unit according to claim 1, wherein the extension unit performs an internal process with reference to the data after the second update unit has completed the update process of the data. Programmable logic controller.

The programmable logic circuit according to any one of claims 1 to 15, wherein the second update unit executes the data update process during a period when the extension unit is not executing an internal process. controller.

The expansion unit is
A first buffer for storing the data updated by the second update means;
A second buffer for storing data referred to by internal processing of the extension unit;
Further comprising third update means for updating the data stored in the first buffer and the data stored in the second buffer so that the data stored in the second buffer coincide with each other when the synchronization means executes a synchronization process;
The programmable logic controller according to claim 1, wherein the second update unit executes the update process after the third update unit completes the update process.

A basic unit that is connected to an expansion unit of a programmable logic controller and repeatedly executes a user program for each scan.
The expansion unit is
An interface to which an external device is connected;
A storage unit in which a device value related to an input value from the external device via the interface or an output value to the external device via the interface is stored, and a device for sharing data with the basic unit is allocated;
An expansion unit timer that counts the clock and measures time,
With
The basic unit is
A basic unit timer that counts the clock and measures time,
Synchronization means for synchronizing the timer values of the extension unit timer and the basic unit timer;
First update means for matching the data held by the extension unit and the data held by the basic unit within a refresh period for each scan;
Based on the timer value of the basic unit timer synchronized with the timer value of the extension unit timer by the synchronization means, the data held by the extension unit within the period of processing executed at regular intervals during scanning and the basic Second update means for matching the data held by the unit;
With
The basic unit is characterized in that the device of the extension unit described in the user program can be set as an update target by the first update means and / or an update target by the second update means. .

A control method of a basic unit connected to an extension unit of a programmable logic controller and repeatedly executing a user program for each scan,
The expansion unit is
An interface to which an external device is connected;
A storage unit in which a device value related to an input value from the external device via the interface or an output value to the external device via the interface is stored, and a device for sharing data with the basic unit is allocated;
An expansion unit timer that counts the clock and measures time,
With
The control method is:
A basic unit timer that counts clocks and measures time; a synchronization step that synchronizes the timer values of the extension unit timer and the basic unit timer;
A first update step of matching the data held by the extension unit with the data held by the basic unit within a refresh period for each scan;
Based on the timer value of the basic unit timer synchronized with the timer value of the extension unit timer by the synchronization step, the data held by the extension unit within the period of processing executed at regular intervals during scanning and the basic A second update step for matching the data held by the unit;
Have
The basic unit characterized in that the device of the extension unit described in the user program can be set as an update target by the first update step and / or an update target by the second update step. Control method.

A program for causing a computer to execute each step of the control method according to claim 19.