JP2002014706A - I/o unit and programmable controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an I/O unit and a programmable controller which permit timer output by a user under arbitrary conditions and in arbitrary timing without fixedly providing any specific operation mode nor mounting a programming function on a unit. SOLUTION: At the start of a timer output instruction, a CPU 25 sets the clock frequency of a pulse generator 33 and presets the clock count number of a hardware counter 35, and also starts outputting a general signal from a general port 25a to an AND circuit 36 at the same time. Consequently, the AND circuit 36 remains ON at the timer output instruction start until the output of the general signal from the CPU 25 and a count-up signal from the hardware counter 35 to the AND circuit 36 is turned OFF.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an I / O unit and a programmable controller of a programmable controller, and more particularly, to a high-precision timer output function by mounting a programming function on the I / O unit or the programmable controller. The present invention relates to an I / O unit and a programmable controller.

[0002]

2. Description of the Related Art Conventionally, in a programmable controller (programmable logic controller) system, units such as a CPU unit and an I / O unit (input / output unit) are arranged in a building block type to form a system (a so-called set). Unit type).

A CPU unit executes a calculation of a user program based on an input signal (contact information) from an I / O unit or the like, performs processing such as outputting an execution result to the I / O unit, and performs processing such as a programmable controller system. Overall control of the whole.

[0004] An I / O unit is a unit to which a device to be controlled in a programmable controller system is directly connected.
In addition to sending the signal to the unit, the output signal from the CPU unit is received and sent to the device to be controlled.

Here, there are the following realization methods for realizing the timer function in the programmable controller system. (A) In a CPU unit, a method of implementing a program by a timer instruction and an OUT instruction by a ladder program. (B) A method in which a timer function is incorporated in an I / O unit (high-performance I / O unit) as an operation mode and output is performed for a time specified by the I / O unit under predetermined conditions.

The high-performance I / O unit is
An I / O unit with new functions added to the existing I / O unit for the purpose of reducing the load on the CPU unit, shortening the scan time, etc.
/ O unit.

Here, the timer function of the CPU unit (a) based on the ladder program will be described with reference to FIG. 11. A timer instruction is started when the output start condition in the cyclic processing (1) is satisfied. Thus, the timer is set in (2), the output instruction is executed when the output start condition is satisfied in (3), and the output is executed to the outside by the IORF (IO refresh) instruction.

Next, when a time-up is detected in the cyclic processing in (4), a reset instruction is executed,
The execution result is output to the outside by an IORF (IO refresh) instruction in (5), and is output to the outside if a time-up is detected in (4), that is, END after one round of execution of the user program. It is not output externally during refresh.)

FIG. 12 is a time chart showing the processing of FIG. 11 described above. In FIG.
In (2), the timer starts a count interrupt at time t2, and thereafter, a count interrupt is performed until time t4 when the output is turned off by an interrupt, cyclic sense, or the like, and the external output of (3) is Starting at time t3, the output is turned off at time t5.

In FIG. 12, the delay time D1 of the external output start time t3 with respect to the output start command time t1 is an overhead until external output, and the delay time D2 of the external output OFF time t5 with respect to the timer interrupt OFF time t4. Is the overhead until the output is turned off.

The delay time D1 of the external output start time t3 with respect to the output start instruction time t1 is based on the fact that the output start instruction of (1) in FIG. This is because two instructions (1) and (2) are inserted before the external output.

Further, the delay time D2 of the external output OFF time t5 with respect to the timer interrupt OFF time t4 is due to the fact that the time-up is detected in the cyclic processing.

[0013]

However, the timer functions of the conventional CPU unit and I / O unit (high-performance I / O unit) as described above have the following problems.

First, the case where the timer function is realized by the CPU unit (a).

(A) Since the timer instruction itself is counted and counted up during the cyclic processing in the ladder program, variations occur due to variations in cycle time and the like, and the error with respect to the designated time is large.

In FIG. 11, a timer instruction is started in the cyclic process (1), and time-up is detected in the cyclic process (4). As described above, since the count operation is performed cyclically in the instruction, the time accuracy is not good.

(B) In FIG. 11, the output instruction is executed when the output start condition is satisfied in (3) and output to the outside by an IORF (IO refresh) instruction. 2) The overhead for processing two instructions occurs before output starts. If the IORF (IO refresh) instruction is not used, the overhead is further increased because the external output is provided by the ENDRF (END refresh).

As described above, since the timer instruction and the OUT instruction operate separately, the overhead time until the output operation is performed is long.

(C) In order to increase the timer accuracy,
When the count and count-up processes are performed by interrupts, an interrupt occurs as a system, so that interrupts at very short time intervals cannot be used, and therefore, accuracy cannot be improved.

Next, a case where the timer function is realized by the I / O unit (b).

(A) Even if the timer output accuracy is secured by hardware, the conventional high-performance I / O unit
Since the timer output is incorporated as an operation mode assuming a specific operation, the operation mode has no flexibility and cannot be used for purposes other than the set use. That is, it is built in the I / O unit from the beginning.

When the configuration is made up of only hardware,
The flexibility of time setting is low.

(B) A timer count interrupt is started based on a specific output start command and an external output is obtained, so that the timer operation and the output operation are combined, and the accuracy is improved as compared with the CPU unit. However, since an interrupt of the internal timer is used, the process becomes a software process, and in the case of competing with an interrupt prohibiting process, a case where accuracy cannot be maintained occurs.

Therefore, the present invention allows a user to output a timer under arbitrary conditions and timing by combining a timer output instruction and hardware dedicated to timer output without a fixed operation mode. It is an object to provide an I / O unit and a programmable controller which are provided.

[0025]

In order to achieve the above object, the present invention relates to a programmable controller according to the present invention.
The / O unit includes an input / output unit for a user program externally assembled, a rewritable memory for storing the user program fetched from the input / output unit, and a user program for executing the user program stored in the memory. Executing means, a pulse generator for outputting a pulse of a predetermined frequency in accordance with a timer output instruction in the user program, and a hard counter for counting the number of output pulses of the pulse generator, wherein a timer output in the programmed user program is provided. It is characterized in that a timer output instruction is executed under an arbitrary condition or timing by the instruction.

Here, the programmable controller I
The I / O unit is one of the units that constitute the programmable controller system, and is a unit to which a number of control target devices are connected. In the present invention, the I / O unit executes a timer output instruction and performs high precision Realizes a highly flexible timer function.

Next, the input / output section of the user program
This is a portion that communicates with the tool, and in the embodiment is the program input / output unit 21 shown in FIG. In FIG. 1, the program input / output unit 21 is provided on the front of the I / O unit 20, but the mounting position and form are not limited to the embodiment. This input / output unit allows direct connection with a program development tool used when the user performs programming, and allows the program to be uploaded to the tool and downloaded from the tool.

In the embodiment, the rewritable memory for storing the user program fetched from the input / output unit is the PRG memory 27 shown in FIG. It is a rewritable memory. Note that this memory may be provided as an independent dedicated memory as in the embodiment, but may also be used as another memory.

When the program of the I / O unit is changed, all the programs from the tool may be downloaded again via the input / output unit and stored in an arbitrary area of the PRG memory 27. Alternatively, the data may be overwritten and saved.

When a part is to be changed by online editing, a part is uploaded from the PRG memory 27 to the tool, displayed by the tool (for example), the user changes the part by the tool, and then the PRG is changed again. What is necessary is just to send to the memory 27.

Further, the user program executing means for executing the user program stored in the memory is a user program executing means as shown in FIG.
And the CPU 25 shown in FIG.

As described above, according to the present invention, the user can incorporate a user program programmed later into the I / O unit.

That is, the program which is taken in and executed by the I / O unit is a program which the user wants to execute on the I / O unit and which is a customized program separately created by the user. This program is independent of the processing program (system program or user program) executed by the CPU unit of the programmable controller system, and is unique to the I / O unit, such as an I / O control logic and arbitrary arithmetic processing. Is a program that performs A program created by using an external tool, which can be newly created or rewritten (changed or added) by the user, and can be freely programmed by the user.

In the embodiment, the pulse generator which outputs a pulse having a predetermined frequency in response to a timer output instruction in the user program is the pulse generator 33 shown in FIG. The pulse generator can variably set the frequency of the output pulse according to the timer output command. Increasing the pulse frequency increases the timer accuracy, while decreasing the pulse frequency can increase the timer time.

Therefore, the pulse frequency can be variably set according to the purpose of the timer output, and a timer output with a high degree of freedom can be realized.

Further, since the frequency of the output pulse can be variably set by the timer output command, the user can easily variably set the frequency of the output pulse.

The hard counter for counting the number of output pulses of the pulse generator is, in the embodiment, a hard counter 35 shown in FIG.

The hard counter can variably set the number of output pulses according to the timer output command.

Therefore, the number of output pulses can be variably set according to the purpose of timer output, and the number of output pulses can be variably set according to the timer output command, so that the user can easily set the timer value variably.

In the embodiment, the timer output instruction is an output instruction with time designation 70 shown in FIG. 5 which is a timer output instruction.
By setting the clock frequency 72 to 3, the frequency of the output pulse can be variably set, and by setting the clock count 73 to the hard counter 35, the timer value can be variably set.

In the embodiment, as shown in FIG. 3, the pulse generator 33 and the hard counter 35 constitute a timer output circuit 31, and as shown in FIG. ) 23.

Accordingly, the I / O unit can execute a timer output instruction under arbitrary conditions and timing by a combination of the software function in the unit body and the hardware function of the board unit, and can realize a timer function with a high degree of freedom.

The pulse generator and the hardware counter are both hardware.

Therefore, if there is a timer output instruction, the output can be controlled only by hardware processing without going through software processing. A timer function can be realized.

Further, the I / O unit of the programmable controller according to the present invention comprises: an input / output unit for an externally assembled user program; a rewritable memory for storing the user program fetched from the input / output unit; A user program executing means for executing a user program stored in the memory, a pulse generator for outputting a pulse of a predetermined frequency according to a timer output instruction in the user program, a predetermined output time set by the timer output instruction, and A hard counter that counts the pulses output from the pulse generator based on the set output time; and an AND that outputs a timer to the outside when a start output of the timer output instruction and a count-up signal of the hard counter are input.
And outputting a timer under an arbitrary condition or timing according to a timer output instruction in the programmed user program.

Here, a predetermined output time is set by the timer output command, and counting the pulses output from the pulse generator based on the set output time means a timer output command (shown in FIG. 5). When the clock count number 73 of the output instruction with time designation 70) is set by the output time, the hard counter outputs only the output time set in the clock count number 73 based on the clock frequency 72 set in the pulse generator 33. To count up.

The AND circuit that outputs a timer to the outside when the start output of the timer output instruction and the count-up signal of the hard counter are input is, in the embodiment, an AND circuit 36 shown in FIG. 36 is a general-purpose output 25 of the CPU 25 which is a start output of the timer output instruction.
When "a" and the count-up signal of the hard counter 35 are input, a timer is output to the outside.

Thus, in the present invention, any conditions,
A timer start instruction can be executed at a timing, and a timer function with a high degree of freedom can be realized.

The pulse generator, the hard counter and the AND circuit are all hardware.

Therefore, when there is a timer output instruction, the output can be controlled only by hardware processing without going through software processing, and high-precision processing can be performed without affecting the I / O unit due to interruption as in the prior art. A timer function can be realized.

Further, the I / O unit of the programmable controller according to the present invention comprises: an input / output unit for an externally assembled user program; a rewritable memory for storing the user program fetched from the input / output unit; A user program executing means for executing a user program stored in the memory, a pulse generator for outputting a pulse of a predetermined frequency according to a timer output instruction in the user program, and a predetermined count-up value set by the timer output instruction; A hard counter that counts pulses output from the pulse generator; and an AND circuit that outputs a timer to the outside when a start output of the timer output instruction and a count-up signal of the hard counter are input. Programmed Characterized by timer output at any conditions or timing by a timer output instruction in THE program.

Here, the predetermined count-up value is set by the timer output command, and the counting of the pulses output from the pulse generator means that the timer output command (output command 70 with time designation shown in FIG. 5) is used. In this case, the clock count number 73 is set by the count-up value of the pulse. In this case, the count is performed by the count-up value set in the clock count number 73 at the clock frequency 72 set in the pulse generator 33.

In the embodiment, the AND circuit 36 for outputting a timer to the outside when the start output of the timer output instruction and the count-up signal of the hard counter are input is the AND circuit 36 shown in FIG. 36 is a general-purpose output 25 of the CPU 25 which is a start output of the timer output instruction.
When "a" and the count-up signal of the hard counter 35 are input, a timer is output to the outside.

Thus, according to the present invention, any conditions,
A timer start instruction can be executed at a timing, and a timer function with a high degree of freedom can be realized.

The pulse generator, the hard counter and the AND circuit are all hardware.

Therefore, if there is a timer output instruction, the output can be controlled only by hardware processing without going through software processing. A timer function can be realized.

Further, the I / O unit of the programmable controller according to the present invention comprises: an input / output unit for an externally assembled user program; a rewritable memory for storing the user program fetched from the input / output unit; A user program executing means for executing a user program stored in the memory; a pulse generator for outputting a pulse of a predetermined frequency according to a timer start instruction in the user program; and a pulse output from the pulse generator according to the timer start instruction. A hard counter that counts and outputs externally and stops external output by a timer stop instruction, wherein the hard counter is capable of receiving any condition or timing by a timer start instruction or a stop instruction in the programmed user program. In characterized by timer operation.

Here, the pulse output from the pulse generator is counted and outputted externally by the timer start command, and the external output is stopped by the timer stop command. In the embodiment, the timer start / stop shown in FIG. In the instruction 80, for example, if the predetermined input condition is to instruct the start of the timer operation (when the operation command 83 is activated), the timer operation is started, and the input condition is to instruct the stop of the timer operation. (When the operation command 83 is stopped) means stopping the timer operation.

Thus, according to the present invention, the user can easily specify the timer operation and set the start and stop of the timer.

Further, the I / O unit of the programmable controller according to the present invention comprises: an input / output unit for an externally assembled user program; a rewritable memory for storing the user program fetched from the input / output unit; A user program executing means for executing a user program stored in the memory; a pulse generator for outputting a pulse of a predetermined frequency according to a timer start instruction in the user program; and a pulse output from the pulse generator according to the timer start instruction. A hard counter that counts and outputs externally, and stops external output by a timer stop instruction; and a timer time measuring unit that measures a timer time from a time when the timer of the hard counter is started to a time when the timer is stopped. .

Here, the timer time measuring means for measuring the timer time from the start of the timer to the stop of the timer of the hard counter means a configuration for measuring the ON time of the hard counter. In the embodiment, in FIG. 7, there is a start input at time t1 and a stop input at time t2. in this case,
The hard counter 35 is started at a time t1 by a timer start command, and is stopped at a time t2 by a timer stop command. Therefore, the timer time measuring means measures the time from time t1 to time t2 when the external output is ON. This value is retained as the current value.

Thus, the user can easily measure the operation time of the timer.

Further, the I / O unit of the programmable controller according to the present invention comprises: an input / output unit for a user program externally assembled; a rewritable memory for storing the user program fetched from the input / output unit; A user program executing means for executing a user program stored in the memory; a pulse generator for outputting a pulse of a predetermined frequency according to a timer start instruction in the user program; and a pulse output from the pulse generator according to the timer start instruction. A hard counter for counting, timer current value detecting means for detecting a timer current value of the hard counter, output area setting means for setting a predetermined output area in a predetermined elapsed time band during activation of the timer, Value Current value based timer on the current values is characterized by having a, a determination unit that determines whether or not there is the elapsed time band of a predetermined output area set by the output area setting means.

Here, the timer current value detecting means for detecting the current timer value of the hard counter has a configuration for detecting the current timer value shown in FIG.

In FIG. 8, the current value of the timer is 0
It is detected as an 8-digit current value from (00000000) to FFFFFFFF.

The output area setting means for setting a predetermined output area in a predetermined elapsed time band during the activation of the timer includes a predetermined output area during a timer operation from time 0 (00000000) to FFFFFFFF in FIG. This means setting an output area in the elapsed time band. In FIG.
The set values 1 to 5 are set as output areas in a predetermined elapsed time band.

Accordingly, based on the timer current value detected by the timer current value detecting means, a judging means for judging whether or not the current value is within the elapsed time band of the predetermined output area set by the output area setting means. Means determining whether the current timer value is within any of the set values.

Thus, according to the present invention, it is possible to easily detect the output area set in the predetermined time band during the timer operation.

A programmable controller according to the present invention includes an input / output unit for a user program externally assembled, a rewritable memory for storing the user program fetched from the input / output unit, and a rewritable memory for storing the user program. A user program executing means for executing the user program, a pulse generator for outputting a pulse of a predetermined frequency according to a timer output command in the user program, a hard counter for counting the number of output pulses of the pulse generator according to the timer output command, And executing the timer output instruction under an arbitrary condition or timing by a timer output instruction in the programmed user program.

In the above description, the board for realizing the timer function is provided in the I / O unit.
When realizing the O function, a board for realizing the timer function can be provided in the programmable controller unit. In this case, the program developed by the personal computer 10 is downloaded to the programmable controller unit instead of the I / O unit.

[0071]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an I / O unit of a programmable controller and a programmable controller according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a schematic block diagram showing an outline of a development environment for unit programs mounted on an I / O unit according to this embodiment.

In FIG. 1, reference numeral 10 denotes a personal computer as a unit program development tool mounted on an I / O unit (high-performance I / O unit) 20 for developing programs online and offline.

The program developed on the personal computer 10 is downloaded to the I / O unit 20 using a serial I / F. For this purpose, the I / O unit 20 has a program input / output unit 21 for downloading. PC 1
0 is downloaded to the I / O unit 20 via the program input / output unit 21.

On the surface of the I / O unit 20, in addition to the program input / output unit 21, a general-purpose digital input / output unit 22 to which an input / output device to be controlled is connected, and a timer function for realizing a timer function. An input / output unit 23a to which an input / output device to be controlled by a board (not shown) mounted therein is connected is provided.

In FIG. 1, reference numeral 60 denotes a building block type programmable controller system, which includes a CPU unit 40 and two I / O units 20-.
1, 20-2. Therefore, the program developed on the personal computer 10 is transmitted to the CPU 10 via the CPU unit 40.
It may be configured to transfer the data to the / O unit 20-1 (I / O unit 20). In this case, the personal computer 10
Are downloaded to the I / O unit 20-1 via the communication port 41 of the CPU unit 40 and the dedicated bus 61 of the programmable controller system.

In FIG. 1, a board for realizing the timer function is provided in the I / O unit 20. However, when the CPU function and the I / O function are realized by one programmable controller unit, the programmable controller unit is used. Can be provided with a board for realizing a timer function. In this case, the personal computer 10 is connected to the programmable controller unit in place of the I / O unit 20.
The program developed in is downloaded.

In the following description, the I / O unit 2
A case where a board that realizes the timer function is provided at 0 will be described.

FIG. 2 shows the I / O unit 20 shown in FIG.
FIG. 2 is a block diagram showing an electrical configuration of the embodiment.

In FIG. 2, an I / O unit 20 includes a program execution unit 30 and a timer output circuit unit (board unit) 2.
The program execution unit 30 includes a general-purpose digital input / output unit 22, a bus I / F device 24, a CPU 2
5, a ROM 26, a PRG memory 27, and a variable memory 28, and the timer output circuit unit 23 includes a plurality of timer output circuits 31-1, 31-2,..., 31-n.

The general-purpose digital input / output unit 22 is connected to a device to be controlled in the programmable controller system, and is composed of a plurality of input contacts and output contacts.

The bus I / F device 24 is connected to the dedicated bus 61 of the programmable controller system 60, and interfaces with the bus 61.

The CPU 25 controls the entire I / O unit 20. In the present embodiment, the CPU 25 is mounted on the timer output circuit 23 based on a user program programmed by the personal computer 10 shown in FIG. Controls the timer output circuits 31-1, 31-2,..., 31-n.

The ROM 26 stores a system program executed by the CPU 25.

The PRG (program) memory 27 is a memory in which a user program programmed by the personal computer 10 is downloaded.

The variable memory 28 stores various control data when the CPU 25 controls the timer output circuits 31-1, 31-2,..., 31-n.

The timer output circuit unit 23 is a board on which a timer function is realized. In this embodiment, the timer output circuit unit 23 includes a plurality of timer output circuits 31-1, 31-2,..., 31-n. It is configured such that a high-precision timer output can be output to the outside under arbitrary conditions and timing.

FIG. 3 shows the timer output circuit 31 shown in FIG.
(Timer output circuits 31-1, 31-2,..., 31-n
Is represented by a timer output circuit 31) and the CPU 25
FIG. 4 is a block diagram showing the details of.

In FIG. 3, the timer output circuit 31 includes a clock generator 32, a pulse generator 33, a hard counter 35, and an AND circuit 36.

Here, the clock generator 32 is for generating a clock with an accurate timing.

The pulse generator 33 oscillates a clock serving as a source for generating time based on the output of the clock generator 32. The frequency (clock rate) of the oscillation clock can be set arbitrarily. I have.

The hard counter 35 counts the pulses output from the pulse generator 33. As will be described later, a timer time is preset when the timer output command is activated, and at the same time, the AND circuit 3
6 is turned on by the AND circuit 3
6 is output.

As described later, the hard counter 3
Reference numeral 5 can be used not only in a timer function for measuring a fixed time, but also in a measurement mode for measuring the time elapsed since the timer was turned on.

The AND circuit 36 is an output gate circuit that is turned on when there is a count-up signal from the hard counter 35 and a general-purpose output from the CPU 25.

The CPU 25 activates the timer output instruction
The setting of the clock frequency in the pulse generator 33 and the presetting of the clock count number in the hard counter 35 are performed.
The output of the general-purpose signal to the D circuit 36 is started. Thus, when the timer output instruction is activated, a general-purpose signal is output from the CPU 25 to the AND circuit 36, and a count-up signal is output from the hard counter 35.
6 turns ON.

FIG. 4 is a block diagram of the hard counter 3 shown in FIG.
5 is a time chart showing the operation of the AND circuit 36 and the CPU 25.

In FIG. 4, when a timer command is started at time t1, a preset value, that is, a timer time T is set in the hard counter 35 as shown in (1).

Thus, the hard counter 35 is started up as a timer as shown in (2), and simultaneously outputs a count-up signal to the AND circuit 36 for the timer time T as shown in (3).

At the same time, as shown in (4), the CPU
The 25 general-purpose ports 25a output general-purpose signals to the AND circuit 36.

As a result, as shown in (5), AND
In the circuit 36, the count-up signal from the hard counter 35 and the general-purpose signal from the CPU 25 are ANDed.
The AND circuit 36 is turned on until the time t2 when the timer time T ends.

FIG. 5 shows an output instruction with a time designation (timer output instruction) executed by the CPU 25 in FIGS. 3 and 4. Output instruction with time designation 70 shown in FIG.
Is an application instruction that is activated when a predetermined output start condition is satisfied. The output destination of the AND circuit 36 shown in FIG. 3 (there is a plurality of timer output circuits 31 and a plurality of AND circuits 36 as shown in FIG. 2). A terminal number 71, a clock frequency 72 set in the pulse generator 33 which is a source of time generation,
The clock count 73 set in the hard counter 35 for determining the output time is set.

As a result, the timer output circuit 31 outputs a timer of the set count number to the set output destination at the set clock frequency.

The clock frequency 72 set in the pulse generator 33 can be fixed, and the output time can be set instead of the clock count number 73.

As described above, in the present embodiment, (1) the user sends an I / O unit
/ O control logic, a function of inputting a program for arithmetic processing, (2) an output instruction 70 with a time designation that can designate an arbitrary output time by designating a specific output destination, and (3)
A pulse generator 33 whose frequency can be changed, (4)
A hard counter 35 that sets a timer time based on a timer output command from the CPU 25 and outputs a count-up signal to the AND circuit 36; (5) a count-up output from the hard counter 35 and a general-purpose output from the CPU 25 And an AND circuit 36 that outputs a timer to a predetermined external terminal, so that the following effects can be obtained.

(1) Since the timer output instruction can be executed under arbitrary conditions and timing using the programming function of the I / O unit 20, a timer output with high accuracy and high flexibility can be obtained. (2) The time range that can be realized because the pulse generator 33 whose frequency can be changed is used as the timer function.
Wide accuracy range. (3) The specified time is measured by the pulse generator 33, the hardware counter 35, and the AND circuit 36 after execution of the timer output instruction, and all of them are performed by hardware. That is,
After execution of the timer output instruction, no software processing is performed.
Accordingly, high-precision timer control can be performed without affecting the I / O unit 20 due to the interruption.

In FIG. 5, the predetermined time is measured by the output instruction with time designation (timer output instruction) 70. Next, the start and stop of the timer are realized by using the hard counter 35. The case will be described with reference to FIG.

The timer start / stop instruction (timer start instruction) 80 shown in FIG. 6 is an application instruction that is started when a predetermined start or stop condition is satisfied, and includes a timer number (number of the hard counter 35) 81 and a time generation , A clock frequency 82 set in the pulse generator 33 and a start or stop operation command 83 are set.

Accordingly, the timer operation is performed from the hard counter 35 set by the timer number 81 at the clock frequency set by the clock frequency 82 in the operation mode set by the operation command 83.

For example, if the predetermined input condition instructs the start of the timer operation (when the operation command 83 is activated), the timer operation starts, and the input condition instructs the stop of the timer operation. (When the operation command 83 is stopped), the timer operation is stopped.

As a result, in the present invention, the timer activation /
Timer start and timer stop can be executed by the stop instruction.
The user can easily start and stop the timer.

In FIG. 6, a timer start / stop command (timer start command) 80 causes a hard counter 35 to operate.
FIG. 7 shows a case where the time from when the hard counter 35 starts to when the hard counter 35 stops can be measured by the timer start / stop instruction 80. This will be described with reference to FIG.

FIG. 7 shows a case where the start input of (1) is at time t1 and the stop input of (2) is at time t2.

In this case, in (3), the hardware of the hard counter 35 is started at time t1 and stopped at time t2.

As a result, in (4), the timer (hard counter) is determined to be measuring from time t1 to t2, and the time from start to stop (current value) after the timer is stopped.
Can be held.

As described above, in FIG. 7, the time from when a certain counter (timer output circuit 31) starts to when it stops can be measured. Moreover, in this case, as shown in FIG. 6, the clock frequency 82 set in the pulse generator 33 can be variably set. Therefore, highly accurate time measurement and measurement time width can be set according to the application.

The hard counter 3 being measured in (4)
The value of 5 can be constantly reflected in the variable memory 28 and monitored.

Next, another example in which the hard counter 35 is used in the measurement mode will be described with reference to FIG.

In FIG. 8, the hard counter 35 indicates the time 0 (0
From 000000) to time FFFFFFFF, a timer operation is performed as a free-run counter.

Here, the user can set an arbitrary elapsed time band as an output area by a program for a timer operating as a free-run counter. For example, in FIG. 8, an output area from a set value 1 to a set value 5 is set in an arbitrary elapsed time band. Here, in the present embodiment, it is possible to detect which output area is in the elapsed time band of the current timer value.

For example, when the current timer value is between t1 and t2, the current timer value is in the elapsed time band between the set value 1 and the set value 4. Therefore, when the current timer value of the hard counter 35 is between t1 and t2, in the present embodiment,
It can be seen that the elapsed time is in the output area of the set value 1 and the set value 4.

FIG. 9 shows a table comparison instruction for detecting the output area as described above. Table comparison instruction 90
Is an application instruction for registering each output area shown in FIG. 8, and is composed of a timer number (number of the hard counter 35) 91, a designated operation mode 92, and a comparison table address 93.

Here, the timer number (hard counter 35
The number 91) is the number of the hard counter 35 that counts the current value.

The designated operation mode 92 is an operation mode of the table comparison instruction. For example, as shown in FIG. 8, when the output area is set with a certain width, this is indicated, and when the output area is set with dots. Indicates the operation mode to that effect.

The comparison table address 93 is a setting address of each set value in the comparison table 100 shown in FIG.

FIG. 10 shows the comparison table 100. In FIG. 10, comparison values for output area detection are registered for 16 output areas.

Each output area shown in FIG. 8 is defined by its lower limit (start time) and upper limit (end time), and each value is registered with eight digits.

Therefore, in the comparison table 100, the number column 101 for comparison (16 in this embodiment) and (1) the lower 4 digits and the upper 4 digits for specifying each output area (the lower 4 digits and the lower 4 digits, respectively) (2) Lower 4 digits and upper 4 digits of upper limit value (8 digits of upper limit can be specified thereby) (3) Output pattern of output area is registered.

Therefore, in the comparison table 100, in order to register the set value 1, (1) set value 1 lower limit lower 4 digits 1
10-1a and (2) Upper 4 digits of setting value 1 lower limit value 110-
1b, and (3) set value 1 upper limit lower 4 digits 110-1c
And (4) setting value 1 upper limit upper 4 digits 110-1d,
(5) The set value 1 output pattern 110-1e is registered.

The same applies to the setting value 2 and below. To register the setting value 16, (1) setting value 16
0-16a and (2) set value 16 lower limit upper 4 digits 110
-16b and (3) lower limit 4 digits 110 of set value 16 upper limit value 110-
16c and (4) Set value 16 Upper limit upper 4 digits 110-1
6d and (5) set value 16 output pattern 110-16e
Is registered.

Here, the table comparison instruction 90 shown in FIG.
Is executed, (1) the current timer value of the hard counter 35 specified by the timer number (number of the hard counter 35) 91 (2) the setting information of each output area set in the comparison table 100 of FIG. Based on this, it is determined whether or not the current timer value is in the search target output area.

The comparison result is output to the variable memory 28 every time the instruction is executed.

If it is determined that the current timer value is in the search target output area, the output pattern of the output area is output. For example, assuming that the output pattern of each output area is output in a specific bit pattern, the detected bit pattern of the output area is output.

[0133]

As described above, according to the present invention, an input / output section of a user program externally assembled, a rewritable memory for storing a user program fetched from the input / output section, User program execution means for executing a user program stored in a memory, a pulse generator for outputting a pulse of a predetermined frequency according to a timer output instruction in the user program, and a hard counter for counting the number of output pulses of the pulse generator. And the timer output instruction is executed under an arbitrary condition or timing according to the timer output instruction in the programmed user program.

Therefore, the present invention has the following effects. (1) The pulse frequency can be variably set depending on the purpose of timer output, and timer output with a high degree of freedom can be realized. Further, since the frequency of the output pulse can be variably set by the timer output command, the user can easily variably set the frequency of the output pulse. (2) The number of output pulses can be variably set according to the purpose of timer output, and the number of output pulses can be variably set according to a timer output instruction. (3) Both the pulse generator and the hardware counter are hardware. Therefore, if there is a timer output instruction, the output can be controlled only by hardware processing without going through software processing, and a high-precision timer function can be provided without affecting the I / O unit by interruption as in the past. realizable.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing an outline of a development environment of a unit program mounted on an I / O unit to which the present invention is applied.

FIG. 2 is a block diagram showing details of an I / O unit 20 shown in FIG. 2;

3 shows a timer output circuit 31 and a CPU 25 shown in FIG.
FIG.

FIG. 4 is a time chart showing operations of a hard counter 35, an AND circuit 36, and a CPU 25 shown in FIG.

FIG. 5 is an explanatory diagram of a time-specified output instruction executed by the CPU 25 in FIGS. 3 and 4;

FIG. 6 is an explanatory diagram in the case of realizing start and stop of a timer using a hard counter 35;

FIG. 7 is an explanatory diagram of a case where the time from when the hard counter 35 is started to when it is stopped can be measured by a timer start / stop instruction.

FIG. 8 is an explanatory diagram showing another example when the hard counter 35 is used in the measurement mode.

FIG. 9 is an explanatory diagram of a table comparison instruction for enabling detection of a set range of a current timer value.

FIG. 10 is an explanatory diagram of a comparison table used in the table comparison instruction of FIG. 9;

FIG. 11 is an explanatory diagram of a case where a timer instruction is implemented by a ladder program and an OUT instruction in a CPU unit in a conventional programmable controller system.

FIG. 12 is a time chart showing the processing procedure of FIG. 11;

[Explanation of symbols]

10 PC 20, 20-1, 20-2 I / O unit (high-performance I
/ O unit) 21 Program input / output unit 22 General-purpose digital input / output unit 23a Board insertion port 23 Timer output circuit unit 24 Bus I / F device (shared memory) 25 CPU 26 ROM 27 PRG memory 30 Program execution unit 31 Timer output circuit 60 Programmable controller system 61 Dedicated bus 70 Output instruction with time designation 71 Output destination terminal number 72 Clock frequency 73 Clock count number 80 Timer start / stop instruction 81 Timer number 82 Clock frequency 83 Start or stop operation instruction 90 Comparison instruction 91 Timer number 92 Specified operation mode 93 Comparison table address

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H220 BB07 BB11 CC03 CC08 CX01 CX05 EE09 EE12 JJ17 JJ34 JJ42

Claims (8)

[Claims] 1. An input / output unit for a user program externally assembled, a rewritable memory for storing a user program fetched from the input / output unit, and a user program for executing the user program stored in the memory Execution means; a pulse generator for outputting a pulse of a predetermined frequency in response to a timer output instruction in the user program; and a hard counter for counting the number of output pulses of the pulse generator. The timer output in the programmed user program An I / O unit of a programmable controller, which executes a timer output instruction under an arbitrary condition or timing by an instruction. 2. An input / output unit for a user program externally assembled, a rewritable memory for storing a user program fetched from the input / output unit, and a user program for executing the user program stored in the memory Executing means, a pulse generator for outputting a pulse of a predetermined frequency according to a timer output instruction in the user program, and a predetermined output time set by the timer output instruction, and from the pulse generator based on the set output time. A hard counter that counts the output pulses; and an AND circuit that outputs a timer to the outside when a start output of the timer output instruction and a count-up signal of the hard counter are input, and the programmed user program is provided. Timer output instruction in Programmable controller I / O unit, characterized in that the timer output in any conditions or timing I. 3. An input / output unit for a user program externally assembled, a rewritable memory for storing a user program fetched from the input / output unit, and a user program for executing the user program stored in the memory Executing means, a pulse generator for outputting a pulse of a predetermined frequency according to a timer output command in the user program, and a hardware for setting a predetermined count-up value by the timer output command and counting pulses output from the pulse generator A starter output of the timer output instruction and an AND circuit that outputs a timer to the outside when the count-up signal of the hard counter is input, and an arbitrary condition is set by the timer output instruction in the programmed user program. Or ta Programmable controller I / O unit, characterized in that the timer output timing. 4. An input / output unit for a user program externally assembled, a rewritable memory for storing a user program fetched from the input / output unit, and a user program for executing the user program stored in the memory An execution means, a pulse generator for outputting a pulse of a predetermined frequency according to a timer start instruction in the user program, a pulse output from the pulse generator according to the timer start instruction, external output, and an external output according to a timer stop instruction And a hard counter for stopping the timer. The hard counter operates the timer under an arbitrary condition or timing according to a timer start instruction or a stop instruction in the programmed user program. / O unit. 5. An input / output unit for a user program externally assembled, a rewritable memory for storing a user program fetched from the input / output unit, and a user program for executing the user program stored in the memory An execution means, a pulse generator for outputting a pulse of a predetermined frequency according to a timer start instruction in the user program, a pulse output from the pulse generator according to the timer start instruction, external output, and an external output according to a timer stop instruction And a timer counter for measuring a timer time from when the timer of the hard counter is started to when the timer is stopped. An I / O unit for a programmable controller, comprising: 6. An input / output unit for a user program externally assembled, a rewritable memory for storing a user program fetched from the input / output unit, and a user program for executing the user program stored in the memory Executing means, a pulse generator for outputting a pulse of a predetermined frequency according to a timer start instruction in the user program, a hard counter for counting pulses output from the pulse generator according to the timer start instruction, and a timer current value of the hard counter Current value detecting means for detecting a current value, an output area setting means for setting a predetermined output area in a predetermined elapsed time band during activation of the timer, and a timer current value detected by the timer current value detecting means. The current value is set by the output area setting means. Programmable controller I / O unit, characterized in that it has a, a determination unit that determines whether or not there is the elapsed time band of a predetermined output area that is. 7. The programmable controller according to claim 1, wherein said hard counter outputs a timer to an I / O designated by said timer output instruction.
/ O unit. 8. An input / output unit for a user program externally assembled, a rewritable memory for storing a user program fetched from the input / output unit, and a user program for executing the user program stored in the memory Executing means, a pulse generator for outputting a pulse of a predetermined frequency in accordance with a timer output instruction in the user program, and a hard counter for counting the number of output pulses of the pulse generator in accordance with the timer output instruction. A programmable controller that executes a timer output instruction under an arbitrary condition or timing by a timer output instruction in a user program.