JPS5850031A - Time correcting system for computer - Google Patents

Abstract

PURPOSE:To secure the uniformity and the precision of a processing, by executing the correction plural times for an overall correction quantity and correcting a unit correction quantity every one step of the correction. CONSTITUTION:In the conventional device, a timer correcting part 6 is connected to a timer processing mechanism 4. In case that the time in a computer which is slow is set forward, a unit correction quantity is subtracted from the preset value of a timer processing mechanism 3 to generate a driving signal 13 for the elapse of T-(the unit correction quantity) to the required time T of time counting, and thus, the current time in the computer is set forward by the unit correction quantity. In case that the time in the computer which is fast is set backward, the preset value is added to the unit correction quantity to generate the driving signal 13 for the elapse of T+(the unit correction quantity) to said required time T, and thus, the current time in the computer is set backward by the unit correction quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a time correction method for a computer, and more particularly to a time correction method for a computer suitable for a computer that performs measurement control of a process.

FIG. 1 is a block diagram of a conventional timer processing device used in an electronic computer.

The oscillator output pulse 11 of several tens of MHz generated by the crystal oscillator 1 is reduced to 100 MHz by the frequency reduction device 2.
~I MHz timer base output reduced to 12,
The timer processing mechanism [F]3 is driven. This timer processing system 3 is a preset timer counter 5.
is counted down, and when the count is completed, a drive signal 13 is output to the timer processing mechanism (S) 4. The flowchart in FIG. 2 shows this process. The timer processing mechanism (S) 4 which receives the drive signal 13 as an input signal is driven by the drive signal 13, and T=NX based on the previously preset value N and the timer base time t (reciprocal of the timer base frequency).
It recognizes the time lapse image with respect to t and performs time measurement (actual update of the current time). The flowchart in FIG. 3 shows this process. This update process takes, for example, t = l m seconds, N = 10
If it is set to 00, it is recognized that T=1 second has passed, and the time in the computer is incremented by 1 second.

In such conventional timekeeping mechanisms, 10"' to 10-4
Due to the error of the crystal oscillator, the time measurement error is several seconds to several minutes per month, and the time must be corrected periodically.The correction is generally performed every 1 to 10-odd days.

However, such conventional correction processing has two drawbacks. That is, the first is the occurrence of double passage in the same time zone when the time is set back, or the appearance of a blank time zone when the time is advanced. , 5 minutes, and 1 hour).For example, the time integrated value for a time period in which the time is advanced by 1 minute has an error of about 22%.

An object of the present invention is to provide a time correction method for a computer that can perform time correction necessary to ensure uniformity and accuracy of processing.

The present invention focuses on the fact that the drawback of conventional time correction is that the accumulation of long-term errors over several days is corrected at once when a correction is requested, and converts the total correction amount into a unit correction amount and the number of corrections. The correction is performed by selecting a combination of the unit correction amount and the correction execution time interval for the unit correction amount in a system-permissible combination.

FIG. 4 is a block diagram showing an embodiment of the present invention. Fifth
The figure is a processing flowchart of the embodiment of FIG. 4. Fourth
In the figures, the same reference numerals are used for the same members as those shown in FIG.

Furthermore, this embodiment deals with a case where the correction execution interval is made the same as the time measurement interval. In this embodiment, as is clear from FIG. 4, a timer correction section 6 is connected to the timer processing mechanism 4, and the timer correction section 6 has the functions of determining a correction request, a unit correction amount, and the number of corrections. have,
Based on this, the timer processing mechanism 4 performs update processing.

The other configurations and functions are the same as those shown in FIG. 1, so their explanations will be omitted.

If the internal time in the computer is delayed and you want to advance it, by dividing the preset value of the timer processing mechanism 3 into the unit correction amount, the drive will be started at the elapsed time of (T - unit correction amount) for the required time interval T. A signal 13 is generated, and the current time in the calculation table can be advanced by the unit correction amount.

In addition, if the internal time in the computer is advanced and becomes "cloudy", by adding the preset value by the unit correction amount, the drive signal 13 occurs, and the current time in the computer can be delayed by the unit correction amount.

According to this embodiment, double passage of time and blank time periods do not occur, and when the data error is maximum, (focal position correction amount /
correction execution interval).

FIG. 6 is a block diagram showing another embodiment of the present invention,
FIG. 7 is a processing flowchart of the embodiment of FIG.

In this embodiment as well, the same reference numerals are used for the same members as shown in FIG. This embodiment is intended for a case where the correction execution interval is made larger than the time measurement interval. This embodiment has a timer correction mechanism 71&: added to the embodiment shown in FIG. It is driven based on the correction processing drive signal 15. The presetting of the timer correction mechanism 7 is performed by the timer processing mechanism 4, and the content of the counter 5, which is counted down by the timer processing mechanism 3, is adjusted by a unit correction amount to advance the drive signal 13 to be output next. or can be delayed.

In addition to the effects of the embodiment shown in FIG. 4, this embodiment has the advantage that the maximum data error can be set arbitrarily.

As described in detail above, according to the embodiments of the present invention, it is possible to prevent double passage of the same time or the occurrence of a blank time period, which conventionally occurred during time correction, and also to prevent data deterioration due to correction, i.e., an increase in errors. can be reduced. To give a specific example, if the unit correction amount is 1 ms, the correction execution interval is 1 second, and the total correction amount is 1 minute, the maximum error is:
0.1%, and the error in the 1-hour value using the conventional method is 1.7%.
, the error in the 15th decimal point was 6.7%, and the error in the 5th minute value was 20%, but this can be greatly improved.

As is clear from the above, according to the present invention, it is possible to ensure the uniformity and accuracy of processing necessary for measurement control.

[Brief explanation of drawings]

1 is a block diagram of a conventional timer processing device, FIG. 2 is a processing flowchart of the timer processing mechanism 3 of the device shown in FIG. 1, and FIG. 3 is a processing flowchart of the timer processing mechanism 4 of the device shown in FIG. 4 is a block diagram showing an embodiment of the present invention, FIG. 5 is a processing flowchart of the embodiment of FIG. 4, FIG. 6 is a block diagram showing another embodiment of the present invention, and FIG.
The figure is a processing flowchart of the embodiment of FIG. 1... Crystal oscillator, 2... Frequency reduction device, 3...
・Timer processing mechanism, 4... Timer processing mechanism, 5.
...Timer counter, 6...Timer correction section, 7.
・・Timer version 5 diagram

Claims (1)

[Claims] 1. In the time correction method of a computer that uses other information to correct the time measurement error caused by the accuracy of the oscillator output of a computer that measures time using the oscillator output pulse as the original information, the total amount of correction is divided into multiple correction execution times. and a time correction method for a computer, characterized in that only a unit correction amount of the correction amount is corrected for each l-step correction.