JPH02195439A - Programmable control device - Google Patents

Abstract

PURPOSE:To eliminate the need for using a timer in 1 st table by setting up a timer in each level, and at the time-up of the level, starting a control module linked to the time-up level. CONSTITUTION:A start period is set up in each level by a monitor program. At the time of generating a request for the formation of each control module, a monitor program linking means obtains the address of a corresponding MCB 1 from a control module number informed at the time of generating the request. After setting up various information in the MCB 1, the address of the corresponding level of an LCB 2 is obtained from the module levels stored in the MCB 1 and the number 4 of registered modules in the level is increased. During the period of operation, the periods 3 of respective levels in the LCB 2 are counted. When the periods of any one of the levels are counted up, an execution state setting means sets up the leading module number 6 in an executing module number 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a programmable control device configured to operate a plurality of control modules through execution management of a monitor program.

[Conventional technology]

Figure 2 is, for example, from the June 1983 issue of Interface (CQ
FIG. 2 is a configuration diagram showing the configuration of each table in the conventional multitask control described in P. 191 to 192 of the publisher (Publisher). In the figure, 1 is a task control block (TCB') provided corresponding to each task.
Information such as a pointer for creating an executable state task list, a time kakunta, a task number (addressed to the task), a task level indicating priority, and a status indicating an executable state is set.

2 is a level control block/(LCB) that is divided into a number of priority levels (level numbers), and is the start address of TCB 1 of the task that is activated first among the tasks included in the corresponding level. is stored.

In the example of FIG. 2, the address of TCB 1 m is stored in the pointer indicating level 0 of LCB 2. Also,
The address of TCBlb is stored in the pointer of TCBla. Thereafter, the settings are made in the same way, and in the end, at level O, TCB 1a m 1 b # 1c.

This indicates that the task corresponding to 1 is in an executable state. Note that TCB 1 corresponds to the first table, and LCB 2 corresponds to the second table.

Next, the operation will be explained. The flowchart shown in FIG. 3 shows the operation of the monitor program when a certain task requests the activation of another task. First, TCB 1 corresponding to nine tasks requested to be activated in step STI
Find the start address of the TCB in step ST2.
Obtain the task level in , and find the position of the corresponding level in LCB2. Then, in step ST3, level 0
T of tasks that belong to and are in executable state
Follow the pointer of CB 1 and find the last TCB 1
The address of TCB 1 of the task requested to be started is set in the pointer. Finally, in step ST4, the status of TCB 1 of the task requested to be activated is set to executable.

Furthermore, the activation timing of tasks that are activated at regular intervals can be determined using a time counter within the TCBI. For example, the monitor program checks the time counters in each TCB I at appropriate timing, and if there is one that is different from a predetermined count value, it performs the processing in steps ST2 to ST4 shown in Figure 3. , set the task to a runnable state.

[Problem to be solved by the invention]

Conventional multi-task control is performed as described above, so when each control module is applied to a programmable control device as each task, it is necessary to operate the time counter in TCB i of all control modules. In addition, registration processing to the LCB2 described above must be performed every time a timeout occurs, resulting in a large dead time during software operation, which impairs real-time performance and has a negative impact on the control module that controls the Grogu2 Mable control device. There were issues such as the effects of

This invention was made in order to solve the above problems, and provides a programmable control device that does not require the time counter in the TCB1 to operate, and as a result, can shorten the dead time during software operation. The purpose is to obtain.

[Means to solve the problem]

In the programmable control device according to the present invention, the monitor program is provided with linking means for registering the control modules in the second table according to the level at the time of generation, and the programmable control device is provided with linking means for registering the control modules in the second table according to the level at the time of generation. , a timer that periodically reaches a predetermined count value is provided, and when the timer times out, execution state setting means is provided for setting the level to an executable state.

[Effect]

The monitor program in this invention registers the generated control module in the corresponding level of the second table when each control module is generated.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 1.1a, 1b, 1c are module control blocks (MCBs) provided corresponding to each control module.
), which is similar to the conventional TCB. 2 is the LCB that sets control information for each execution level, and 3 is the startup cycle (
timer), 4 is the number of registered modules that register the number of control modules included in that level, and 5 is the number of registered modules currently being executed.
Or, the running module tr number indicates the number of the control module to be executed next, 6 is the first module number to be activated at each level, the first module number indicates the number of the control module, and 7 is the first module number to be activated at each level. The ending module number 8 is a ready flag indicating that the timer 3 of each level has timed up.

9 is a next execution module number indicating the number of the control module to be executed next when the execution of the control module corresponding to MCBIK is completed, and corresponds to a conventional TCB pointer.

Next, the operation will be explained. First, the monitor program sets the activation cycle 3 for each level. When a request for generation of each control module occurs, the linking means of the monitor program obtains the address of the corresponding MCB 1 from the control module number notified at the time of the request. Next, after setting various information in MCB1, obtain the address of the corresponding level of LCB2 from the module level (corresponding to the conventional task level) stored in MCBIK, and calculate the number of registered modules at that level. Increment 4.

Here, when the number of registered modules 4 is Ill, both the start module number 6 and the end module number 7 are set to the number of the control module being registered. 111
If not, if there is already a registered control module, the registering control module is added to the next execution module number 9 of MCB 1 c corresponding to the control module indicated by the end module number 7. Set the number. At the same time, the end module number T is set to the number of the control module. Registration of the control module is performed as described above.

During operation of the programmable control device, activation periods 3 for each level of LCB2 are counted in parallel. When any activation cycle 3 counts up, the execution state setting means turns on the ready flag 8 of the corresponding level.
and the first module number 6 is being executed - layer number 5J
C Set. As described above, all control modules registered at that level become executable.

When the monitor program detects a level where the ready flag is in the ON state, it operates the control module from the start address set in MCB1 of the control module corresponding to the module number 5 currently being executed at that level. Let it start. Once the operation of this control module is complete,
Obtain the start address set in the MCB1 of the control module corresponding to the next execution module number 9 of the corresponding MCB1. Thereafter, the contents of the MCBI are sequentially retrieved and each control module at this level is operated.

Here, set the ready flag on MCB1 as well,
The control module corresponding to MCB 1 whose ready flag is not in the ON state can also be controlled to be skipped.

In the above embodiment, the control modules are linked for each level and the activation period 3 is set for each level, but when each control module is registered, those having the same control period may be linked.

〔Effect of the invention〕

As described above, according to the present invention, the programmable control device is configured such that a timer is set for each level, and when the timer times up, the control module linked to the level at which the timer has timed up is activated.
TCB-) There is no need to use the timer in the first table, and the dead time of the seven squares is small.
This has the effect of improving real-time performance.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing the configuration of each table for multitask control in a programmable dual-mable control device according to an embodiment of the present invention, FIG. 2 is a configuration diagram showing the configuration of each table for conventional multitask control, and FIG. FIG. 3 is a 70-chart showing the operation of a conventional monitor program. 1 is TCB or MCB (first table), 2 is L
CB (second table), 8 is ready flag. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] A plurality of control modules divided into functional units, a first table corresponding to each of these control modules and having information including the priority and executable state of each control module, and a first table having information indicating the control module at a level. In the programmable control device, the programmable control device includes a second table that is registered in each case, and a monitor program that starts the control module based on information set in the first table and the second table. providing a linking means for registering each control module in the second table according to the level when the control module is generated, and providing a timer in the second table for each level that periodically reaches a predetermined count value; A programmable control device characterized by comprising execution state setting means for detecting that the timer at an arbitrary level reaches a predetermined count value and setting the level to an executable state.