JPS6285319A - Internal timepiece correcting system for computer - Google Patents

Abstract

PURPOSE:To omit unnecessary or useless updating of an internal timepiece, and also to change an updating period by executing periodically the updating of the internal timepiece in accordance with the updating period which has been designated by a user. CONSTITUTION:A user inputs an updating period data for designating a period for updating the time of an internal timepiece 11 from an input means 11. A setting means 13 writes the inputted updating period data in a storage device. An updating time monitor means 14 starts a start means 15, when the updating period data which has been read out of the storage device and an updating monitor data have coincided. By a start of the start means 15, an updating means 16 is started. The updating means 16 updates the internal timepiece 11 by a time data of an external timepiece 20, which has been read by a read means 17. By executing the updating in this way, unnecessary or useless updating of the internal timepiece can be omitted, and also the updating period can be changed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an internal clock correction method for a computer, and particularly to a computer that periodically updates the time of the internal clock of the computer using time data read from an external clock. Regarding internal clock correction method.

[Conventional technology]

Generally, computers are used to perform time-related controls such as measuring job scheduling and zip processing time during online system operation.

An internal clock is provided that can be read by the program.

This internal clock is created by counting the clock pulses of the logic circuit, and its accuracy is generally not very high, so when operating for a long time, such as 24-hour non-stop operation, the internal clock time may deviate. In order to prevent this, the time of the internal clock was corrected at regular intervals by a more accurate external clock.This correction was done with priority over the user's clock. The period of correction was fixed.

[Problem that the invention seeks to solve]

In the conventional internal clock correction method described above, correction of the internal clock is performed with priority at a fixed cycle, so if this fixed cycle is short, the internal clock is always corrected even when the system load is close to overload. Since correction is performed, the disadvantage is that the throughput of the system will be reduced, and if the fixed period is long, the difference between the internal time and external time will be large, and the correction will be performed. However, when the correction value is large, the time on the internal clock becomes unstable.

[Means for solving problems]

The internal clock correction method of the computer according to the present invention includes an update cycle data setting means for specifying a cycle for updating the time of the internal clock, and an update time monitoring means for monitoring the timing to update the time of the internal clock according to the update cycle data. , an activation means activated by the update timing monitoring means, and an update means activated by the activation means to update the internal clock using time data read from an external clock). [Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. The time is determined by the computer's internal clock correction method that periodically updates the time using the time data of an external clock 20 installed outside the computer, and the update cycle data that specifies the cycle for updating the time of the internal clock 11 is input. Input means 1
2 and.

Update period data is input from this input means 12.

A setting means 13 writes this into a storage device, and an update time monitoring means 14 monitors when to update the time of the internal clock 11 according to this update cycle data.

a starting means 15 that is started by the update timing monitoring means 14; an updating means 16 that is started by the starting means 15 and updates the time of the internal clock 11 using the time data read from the external clock 21; j! It is configured to include a reading means 17 that is activated by the updating stage 16, reads time data from an external clock 20, and sends this time data to the updating means 16.

Next, the operation of this embodiment will be explained. First, the user inputs update cycle data from the input means 12 that specifies the cycle for updating the time of the internal clock 11.
As shown in FIG. 2, the setting means 13 inputs the update cycle data through the update cycle data input 21, writes it into the storage device through the update cycle data storage 22, and initializes the update monitoring data 23. Initialize the update monitoring data.

On the other hand, the internal clock 11 operates the update timing monitoring means 14 at regular intervals asynchronously with the above-mentioned operation.

The update timing monitoring means 14 is as shown in FIG.

The update cycle data read 31 reads the update cycle data written in the storage device by the setting means 13, and the update monitor data read 32 reads the update monitor data. These two data are compared in update judgment 33 to see if they match, and if they do not match, it is determined that it is not time to update the internal clock, and update monitoring data is updated in update monitoring data update 36. Do the following. - If the two match, it is determined that it is time to update the internal clock, and the update monitoring data is returned to its initial state in the update monitoring data initialization 34, and the starting means 15 is started in the starting means activation 35. The starting means 15 activated by the starting means wJ35 activates the updating means 16 at the updating means starting ti141, as shown in FIG. The updating means 16 activates the reading means 17 by means of the reading means activation 51 shown in FIG. As a result, the reading means 17 reads the external clock 61 as shown in FIG.
reads the time from the external clock 20, and sends it to the update means 1=6 by the time data sending 62. The updating means 16 updates the time of this external clock 20 to the time data reception 52.
Then, the internal clock 11 is updated by the internal clock update 53. By repeating the above-described operations, the internal clock 11 is periodically updated according to the update cycle specified by the user.

〔Effect of the invention〕

As explained above, the present invention sets the update timing of the internal clock based on the update cycle specified by the user, and periodically updates the internal clock according to this update cycle, thereby eliminating unnecessary or wasteful information. It is possible to omit updating the internal clock, and the update cycle can be dynamically changed during system operation.
Same as response time of the entire system, reduction in load kg
It has an effect that is easy to perform.

[Brief explanation of drawings]

1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a flowchart showing the operation of the setting means 13, FIG. 3 is a flowchart showing the operation of the update cycle monitoring means 14, and FIG. 4 is a flowchart showing the operation of the activation means 15.
5 is a flow chart showing the operation of the updating means 16, and FIG. 6 is a flow chart showing the operation of the reading means 17.

Claims (1)

[Claims] In the internal clock correction method of a computer, the time of an internal clock that is installed inside the computer and whose time data can be read by a program is periodically updated using the time data of an external clock installed outside the computer. input means for inputting update period data specifying a period for updating the time of the input means; inputting the update period data from the input means;
a setting means for writing this into a storage device; an update time monitoring means for monitoring when to update the time of the internal clock according to the update cycle data; a starting means activated by the update time monitoring means; an updating means that is started and updates the internal clock using time data read from the external clock; and an updating means that is started by the updating means, reads time data of the external clock, and sends the time data to the updating means. reading means, and updating the time of the internal clock with the time data of the external clock according to the cycle specified by the update cycle data inputted from the input means. Clock correction method.