A timing device with controllable second interruption interval

Abstract

The invention discloses a time calibration device with a controllable second interrupt interval. An external main control device transmits time calibration data which is directly input to a time calibration register and a time calibration trigger. The time calibration register inputs the calibration data into an adder. The time calibration trigger transmits a time calibration starting signal to a comparator to drive the comparator to carry out time calibration operations. A clock generator is used to generate a system clock and timing pulses. The timing pulses are input to a timer. The timer updates a current time value according to a time calibration result output by the comparator and records the number of timing pulses. The adder sums up the time calibration data converted by the time calibration register and the time values recorded by the timer. The comparator calibrates time and outputs the time calibration result to the timer. The device solves the problems of too small or too large second interrupt intervals during time calibration and remarkably reduces CPU machine time.

Description

technical field [0001] The invention belongs to the technical field of aerospace electronics and relates to a timing device with controllable second interruption interval. Background technique [0002] Spacecraft generally have their own time system. In actual application, due to various reasons or needs, the time of spacecraft often needs to be corrected multiple times or periodically maintained to meet the use requirements. This involves timing operations. [0003] The traditional timing operation is generally realized by the CPU software. In order to avoid the second interrupt interval being too small or too large during the timing calibration, the software needs to calculate the next second timer Intel according to the specific value of the calibration time before each calibration. The number that the 8254 chip needs to count is written into the counting initial value register of the Intel 8254 chip. The 8254 uses countdown. When counting down from the initial counting...

AI Technical Summary

Problems solved by technology

[0009] In view of this, the present invention provides a timing device with a controllable second interruption interval. The timer is designed through the hardware circuit, and the timing trigger condition is designed using the constraint condition of the second interruption interval. When the timing trigger condition is satisfied, the hardware circuit automatically Realize the timing operation, which solves the problem that the second interrupt interval is too small or too large during the timing adjustment process, and greatly saves CPU time

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