JPH04322310A - Information processor with interval timer - Google Patents

Abstract

PURPOSE:To inexpensively provide an interval timer capable of counting accurate time, to improve the reliability because of a small number of parts, and to easily design hardware by constituting the interval timer with the small number of parts without requiring complicated hardware. CONSTITUTION:This processor is provided with a means which sets a counted value to a down counter 5, a means which reports to a control part 2 that the down counter 5 is 0, and a means which reads the value of the down counter into the reported control part 2 and subtracts the counted value, which should be counted before the write of a calculated value to the down counter 5 after the read of the down counter 5 to the control part 2, from a preliminarily determined initial set value of the down counter 5 and adds the counted value from the report to counted value read as the value of the counter read into the control part 2 to the subtraction result and writes the obtained value in the down counter 5.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing apparatus having an interval timer, and more particularly to an information processing apparatus having an interval timer.

0002

2. Description of the Related Art Conventional information processing apparatuses having an interval timer have been implemented in the following two ways. One is to implement a function in hardware that automatically sets a preset value to the timer when the timer expires. Second, when the timer expires, the expiration of the timer is detected in the computer program and the value is reset in the timer by the computer program.

0003

[Problems to be Solved by the Invention] One of the above-mentioned conventional information processing devices having an interval timer has a hardware function that automatically sets a preset value to the timer when the timer expires. Must be implemented.

[0004] In the second case, when the timer expires,
Since there is a delay before the timer value is reset, and the delay time changes dynamically depending on the running state of the computer program, it has been impossible to realize an accurate interval timer.

[0005]

[Means for Solving the Problems] An information processing device having an interval timer according to a first aspect of the invention includes a down counter that starts counting down again from the maximum value of the counter when the value of the counter becomes 0, and a control unit. The device includes means for setting a count value in a down counter, means for reporting this to a control unit when the down counter reaches 0, and means for reading the value of the down counter into a control unit that receives the report and setting a predetermined value. After the control unit reads the down counter from the initial setting value of the down counter,
Subtract the number of counts that must be counted before writing the calculated value to the down counter, and add to this the elapsed count from the report to the reading of the count value, which is the value of the counter read into the control unit described earlier. The device is configured to include means for writing the determined value into a down counter.

Further, the information processing device having the interval timer of the second invention uses a counter that can simply measure elapsed time instead of the down counter of the first invention, and the expiration value of the counter to be reported to the control unit can be set to an arbitrary value. Configured to set to value.

[0007]

Embodiments Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an information processing apparatus showing an embodiment of the information processing apparatus having an interval timer according to the present invention. The information processing device of this embodiment includes a control unit 2,
A down counter 5 connected thereto, an arithmetic unit 1 that calculates a counter value etc. to be set in the down counter 5, and a counter value that stores the counter value used to set the down counter 5 and its correction value. It is composed of a storage section 3 and a correction value storage section 4. FIG. 2 is an operation flow diagram of the interval timer of the information processing apparatus of this embodiment.

First, the control unit 2 causes the counter value storage unit 3 to store a value obtained by dividing the target interval time by the count period of the down counter 5, and stores the value obtained by dividing the target interval time by the count period of the down counter 5 in the correction value storage unit 4. After reading the value, the value counted by the down counter 5 is stored during the time until the counter value is set in the down counter 5.

In order to operate the interval timer, the value of the counter value storage section 3 is written into the down counter 5. The down counter 5 reports to the control unit 2 when the value reaches 0. The control unit 2 that has received the report uses the calculation unit 1 to calculate the correction value storage unit 4 from the value stored in the counter value storage unit 3.
Subtract the value stored in . Next, the control unit 2 reads the counter value from the down counter 5, adds the calculation result of the process described above and the read counter value in the calculation unit 1, and writes the addition result to the down counter 5.

[0011] From then on, by resetting the counter value according to the above procedure every time the value of the down counter 5 becomes 0, accurate time measurement is possible without changing the interval time depending on the operating state of the control unit 2. An interval timer can be realized.

In the above explanation, the down counter 5 is used as the interval timer, and when the value of the down counter 5 reaches 0, it is reported to the control section 2. However, the interval timer is not limited to the down counter. A method using a counter that can simply measure the elapsed time may also be used. At this time, the expiry value of the counter to be reported to the control unit 2 can be set to any value.

[0013]

[Effects of the Invention] As explained above, the information processing device having the interval timer of the present invention allows an interval timer capable of accurate time measurement to be configured with a small number of parts without requiring complicated hardware. Therefore, it can be provided at a low cost, and since the number of parts is small, reliability is improved, and hardware design is also facilitated.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an information processing device showing an embodiment of the information processing device having an interval timer according to the present invention.

FIG. 2 is an operation flow diagram of an interval timer of the information processing apparatus of the embodiment.

[Explanation of symbols]

1 Arithmetic unit 2 Control section 3 Counter value storage section 4 Correction value storage section 5 Down counter

Claims (2)

[Claims] 1. An information processing device comprising a down counter and a control unit, and an interval timer that reports to the control unit when the value of the down counter reaches 0 and starts counting down again from the maximum value of the counter, wherein the down counter is Upon receiving the report that the down counter has become 0, the control unit reads the value of the down counter, and calculates the down counter value from the reading to the sum of the elapsed count from the report to the reading and the initial setting value of the down counter. An information processing device having an interval timer, characterized in that the calculated value is obtained by subtracting the number of counts to be counted before writing the calculated value to the counter, and the calculated value is written to the down counter. 2. Means for setting a count value in a counter, means for reporting the counter value of the counter when an interval time has elapsed to a control unit, and means for reading the value of the counter into the control unit that has received the report; means for subtracting from the interval time count the number of counts to be counted up to the reading and the number of counts to be counted from the time of reading to the time of writing to the counter from the counter value when the interval time has elapsed; An information processing device having an interval timer, comprising: means for writing a counter value into the counter.