JPS6114548B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has a link interrupt method, in particular, a periodic interrupt processing function that starts at regular intervals, and an input/output interrupt processing function that starts by receiving a report signal from an input/output device. This invention relates to a link interrupt method in a central control unit.

For example, in the central control unit of an electronic exchange,
Call detection, diamond pulse reception counting, etc. are performed by a periodic interrupt processing function that is activated at regular intervals (for example, 4 milliseconds or an integral multiple thereof), and input/output devices are instructed by the central controller. When a report signal reporting that the input/output operation has been completed is transmitted to the central controller, the central controller activates the input/output interrupt processing function and executes post-processing.

FIG. 1 is a diagram showing an example of a conventional interrupt method in this type of central control unit. In FIG. 1, a clock pulse generating circuit 2 in a central control unit 1 sends out a clock signal a at a regular cycle of 4 milliseconds to set a flip-flop 3 indicating the type of interrupt. Further, when the input/output device 4 sends out a report signal b when it completes a predetermined input/output operation, the flip-flop 5 of the central control device 1 is set. When either of the flip-flops 3 and 5 is set, the interrupt section 6 is activated, interrupts the currently executing process, and interrupts the processing that is stored in various registers (not shown) in the central controller 1 at the time of interruption. Execute interruption processing such as temporarily saving the data stored in the storage device,
Also, the set states of flip-flops 3 and 5 are investigated by interrupt analysis processing. If the flip-flop 3 is in the set state, the periodic interrupt processing unit 7 is activated and processes A such as call detection and diamond pulse reception counting are executed. If the flip-flop 5 is in the set state, the input/output interrupt processing section 8 is activated and post-processing B for completing the input/output operation is executed. FIG. 2 is a diagram showing an example of the processing process. In FIG. 2, clock signal a is clocked at times t1, t7 and t1.
1 occurs at a 4-millisecond cycle, interrupting the process C that is being executed and causing the process A to start executing. When the processing A ends at times t2 and t8, respectively, the interrupted processing C is restarted by a known method. On the other hand, the report signal b from the input/output device 4 is not synchronized with the clock signal a at all, and occurs at time t3 (report signal b1), time t
5 (report signal b2) and t9 (report signal b3)
When the process C, which is also being executed, is interrupted, and the corresponding processes B1, B2, and B3 are started. When each process B1, B2, and B3 is completed at times t4, t6, and t10, the interrupted process C is restarted by a known method.

As is clear from the above explanation, the conventional interrupt method interrupts the current process C every time the clock signal a or the report signal b (b1 to b3) is generated.
A required process A or B (B1 to B3) is interrupted and executed. Every time the current process C is interrupted, the central control unit 1 saves the current state to the storage device, and when the interrupt execution process A or B (B1 to B3) is completed, the central control unit 1 saves the current state to the storage device. is restored and processing C is restarted. Therefore, processing A
and B (B1 to B3), the central control unit 1 must execute the interruption process and the restart process regarding process C, which consumes processing capacity. Further treatments A and B
If (B1 to B3) are requested at the same time,
A situation also arises in which a process (for example, B2) with a higher priority requests interruption of the process (for example, B1) that is currently being interrupted, making the interruption process and restart process even more complicated.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the conventional interrupt method as described above, to simplify the interrupt processing and restart processing associated with the interrupt, and to reduce the burden on the processing capacity of the central control unit.

This purpose is to provide a central control device that is equipped with a periodic interrupt processing function that starts at regular intervals and an input/output interrupt processing function that starts in response to a report signal transmitted from an input/output device at any time. This is achieved by enabling the input/output interrupt processing function to be activated based on the report signal received from the input/output device before the time when the periodic interrupt processing function is activated.

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. FIG. 3 is a diagram showing a link interrupt method according to an embodiment of the present invention, and FIG.
It is a figure which shows an example of the processing process in a figure. Third
In the figure, the difference from Figure 1 is that the input/output device 4
The report signal b sent from the floppy circuit is led via the gate 9 to the flip-flop 5 which indicates the type of interrupt. The gate 9 is made conductive by the output of the flip-flop 3, which is set by the clock signal a generated at a regular cycle of 4 milliseconds. Therefore, the flip-flop 5, which is the activation factor for the input/output interrupt processing section 8, is not set immediately at the time of arrival of the report signal b, but is activated by the periodic interrupt processing section 7.
It waits for the flip-flop 3, which is the activation factor, to be set, and then the flip-flop 3 is set. As a result, the activation timing of the interrupt section 6 is limited to the setting timing of the flip-flop 3 (4 millisecond constant cycle).
The interrupt unit 6 activated at that time executes the current process C (fourth process).
If the interrupt processing and interrupt analysis processing shown in the figure) are executed, and flip-flop 5 is set along with flip-flop 3, then after processing A is executed by periodic interrupt processing section 7, input/output interrupt processing section 8 is executed. It starts and executes process B, and then resumes the interrupted current process C. Next, FIG. 4 shows an example of the processing process. First, at time t1, a clock signal a is generated, interrupting the process C that is being executed and starting the process A. Note that no input/output device completed its operation during the 4 milliseconds before time t1, so
When process A ends at time t2, interrupted process C is immediately restarted. Clock signal a is generated at time t7, which is 4 milliseconds after time t1, but until then, report signals b1 and b2 from input/output device 4 arrive at time t3 and t5, respectively. Current processing C continues without interruption until time t7. At time t7, the current process C is interrupted and process A is started, and when process A ends at time t8, the report signal b1 is
Processing B1 corresponding to is started to be executed, and at time t12
When the process B1 ends, the process B2 corresponding to the report signal b2 is further executed. When processing B2 ends at time t13, processing B1 and B2 corresponding to report signals b1 and b2 that arrived during the 4 milliseconds before time t7 are all completed, so that interrupted processing C is restarted. Similarly, process B3 corresponding to report signal b3 (time t9) that arrived during 4 milliseconds from time t7 to time t11 is process A that is executed by interrupting current process C at time t11.
Subsequently, the process is executed from time t14 to t15.

As is clear from the above explanation, according to the present embodiment, the central controller 1 suspends and restarts the current process (times t1, t7, and t11) only once every period (4 milliseconds) in which the clock signal a is generated. By executing the process (times t2, t13, and t15), not only process A but also process B (B1 to B
3) will also all be executed. Therefore, compared to the conventional interrupt method shown in FIG.
1, B2, and B3 become unnecessary.

It should be noted that FIGS. 3 and 4 are only one embodiment of the present invention, and for example, the arrival situation of the report signal b is not limited to that shown in the figure, and it may arrive in any other situation. However, the effect of the present invention remains unchanged.
Further, the generation cycle of the clock signal a is not limited to 4 milliseconds, and many other cycles may be considered, but the effects of the present invention remain the same in either case. Furthermore, it may be considered that the interrupt section 6, the periodic interrupt processing section 7, and the input/output interrupt processing section 8 are configured by using programs together, but the effects of the present invention do not change in such a case.

As described above, according to the present invention, in a central control unit having a periodic interrupt processing function and an input/output interrupt processing function, the frequency of interrupting and restarting the current process for the interrupt processing is determined by the input/output interrupt processing function. This is determined by periodic interrupt processing regardless of the interrupt processing, and the burden on the central control unit due to the interruption processing and restart processing is kept to a minimum, and the interruption processing and restart processing are also simplified.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a conventional interrupt method, and FIG. 2 is a diagram showing an example of the processing process in FIG.
FIG. 3 is a diagram showing a link interrupt method according to an embodiment of the present invention, and FIG. 4 is a diagram showing an example of the processing process in FIG. 3. In the figure, 1 is a central control unit, 2 is a clock generation circuit, 3 and 5 are flip-flops, 4 is an input/output device, 6 is an interrupt section, 7 is a periodic interrupt processing section, and 8 is an input/output interrupt processing section. , 9 is a gate, a is a clock signal, b, b1, b2 and b3 are report signals, A, B and C are processing, and t1 to t15 are times.

Claims (1)

[Claims] 1. In a central control device comprising a periodic interrupt processing function activated at regular intervals and an input/output interrupt processing function activated by a report signal transmitted from an input/output device from time to time, the central control device A link interrupt method characterized in that, at the time of activating the interrupt processing function, the input/output interrupt processing function can be activated based on the report signal received from the input/output device before the time.