KR20020087189A - Method to embody software timer - Google Patents

Abstract

PURPOSE: A method for realizing a software timer is provided, which can generate a number of software timers using one hardware timer. CONSTITUTION: The method includes an initialization step(ST1) of initializing a value of a list to scan when an interrupt of a hardware time is detected, and a list judgement step(ST2) of judging whether a present list number is equal to or lower than the number of lists, and a timer checking step(ST3) of judging whether a time of the software time is expired if there is a software timer registered in a corresponding list of a timer block if the present list number is equal to or lower than the number of lists. In a timer expiration step(ST4), if there is a software timer whose time is expired, related information of the corresponding timer is stored and the corresponding timer is deleted from the timer block, and then the method is recurred to the timer checking step. In an end step(ST6), if the present list number is larger than the number of lists, a message is transferred to a specific work related with the corresponding timer stored in the timer expiration step.

Description

How to implement a software timer {METHOD TO EMBODY SOFTWARE TIMER}

The present invention relates to a timer, and more particularly to a method of implementing a software timer for generating a plurality of software timers using one hardware timer.

Conventional timers are hardware timers, 4 to 8, depending on the type of processor. In a conventional hardware timer, when a timer is registered in a register of a processor, the processor allocates one hardware timer to the timer.

The processor counters an interrupter periodically generated by the hardware timer until the timer expires, and generates an interrupter for a specific task when the timer expires so that the specific task is performed.

Therefore, conventionally, one hardware timer is assigned to one specific task to perform a specific task.

However, in the prior art as described above, there is a problem in that the task cannot be easily performed when the number of timers required for a specific task is larger than the number of actual hardware timers.

Accordingly, an object of the present invention is to provide a method of implementing a software timer that generates and uses a plurality of software timers using one hardware timer.

1 is an exemplary view showing a method of registering a new software timer of the present invention.

2 is a flowchart illustrating a method of implementing the software timer of the present invention.

*** Explanation of symbols for the main parts of the drawing ***

10: First list 11, 12, 13: Software timer registered in the first list

20: 2nd list 21, 22: Software timer registered in 2nd list

30: 3rd list 31, 32: Software timer registered in 3rd list

23: timer with newly registered expiration time of 6

In order to achieve the above object, the present invention provides an initialization step of initializing a value of a list when an interrupt is detected, a list determination step of determining whether a current list number is less than or equal to the number of lists, and in the list determination step. If the current list number is less than or equal to the number of lists, a timer checking step of judging whether there is a software timer registered in the corresponding list, and if there is a software timer, determining whether the timer has expired, and the time of the software timer in the timer checking step. If the timer expires, the timer manager delivers the message and related information to the message router, and the timer expires step of returning to the timer checking step. If the current list number is greater than the number of lists in the list determining step, the message router sends a message to the specific job. relay If there is a message, the message need yahal transmission determines the itneu message router is characterized in that it is configured to terminate step of delivering a message to a particular work and shut down.

Hereinafter, the operation and effect of the method of implementing the software timer according to the present invention will be described with reference to FIGS. 1 and 2.

1 is an exemplary view showing a method for registering a new software timer of the present invention. As shown in the drawing, a software timer block expires in three lists (10, 20, 30) and the lists (10, 20, 30). Each software timer (11, 12, 13, 21, 22, 31, 32) connected in ascending order of time is registered. The software timers 11, 12, 13, 21, 22, 31, and 32 are composed of a corresponding ID, expiration time, work ID, message buffer, and connection information. In addition, a number inside each software timer indicates an expiration time.

The first list 10 includes a software timer 11 having an expiration time of 1, a software timer 12 having an expiration time of 2, and a software timer 13 having an expiration time of 11, and an expiration time in a second list 20. The four-timer software timer 21 and the software timer 22 with an expiration time of seven are included. The third list 30 includes a software timer 31 with an expiration time of three and a software timer 32 with an expiration time of nine. Each is registered and managed in ascending order of expiration time.

When the new software timer 23 having an expiration time of 6 is registered in the above state, three software timers 11, 12, and 13 are included in the first list 10, and two software timers (2) are registered in the second list 20. Since 21 and 22 have two software timers 31 and 32 registered in the third list 30, the new software timer 23 is the fastest second list 20 in the list with the lowest registered software timer. ) Is registered. In addition, since the expiration time is 6, it is registered between the software timer 21 with the expiration time 4 and the software timer 22 with the expiration time 7.

The components necessary to manage the software timers registered in the respective lists include a timer input / output unit for registering and deleting a message to be delivered to a specific task by the user to the software timer, and receiving the periodic interruption from the hardware timer. A timer manager that manages software timers and outputs a corresponding message and related information when a specific software timer expires, and a message that transmits a message registered by a user to a specific job currently operating using information transmitted from the timer manager. It consists of a router.

2 is a flowchart illustrating a method of implementing a software timer of the present invention. As shown in FIG. 2, an initialization step (ST1) of initializing a value of a list upon detecting an interrupt generated periodically by a hardware timer, and a current list number of A list determination step (ST2) for determining whether the number is less than or equal to the number; and if the current list number is less than or equal to the number of lists in the list determination step (ST2), it is determined whether there is a software timer registered in the list. Timer check step (ST3) to determine whether the time of the timer has expired, and if the time of the software timer has expired in the timer check step (ST3), the timer management unit delivers the message and related information to the message router, After deleting the software timer from the list If there is no software timer registered in the list in the timer expiration step (ST4) and the timer checking step (ST3), or if the time of the software timer registered in the list has not expired, the list is returned. If the current list number is greater than the number of lists in the list increasing step ST5 and the list determining step ST2 returns to the list determining step ST2, the message router should deliver the specific job to the specific job. If there is a message to be delivered by determining whether there is a message, the message router is configured and operated by a termination step (ST6) of delivering a message to a specific task, terminating, and terminating if there is no message to be delivered.

As described in detail above, the present invention can generate a plurality of software timers using one hardware timer, thereby facilitating a task requiring a large number of timers or a multitasking task.

Claims (4)

An initialization step of initializing the value of the list to be searched upon detecting an interrupt of the hardware timer, a list determination step of determining whether the current list number is less than or equal to the number of lists, and a number of lists of the current list number in the list determination step. If less than or equal to the timer check step of determining whether there is a software timer registered in the corresponding list of the timer block, and if there is a software timer, the timer check step of determining whether the time of the software timer has expired, A timer expiration step of storing the relevant information of the timer and deleting the timer from the timer block, and returning to the timer confirmation step; and if the current list number is greater than the number of lists in the list determination step, the timer expires step. And a termination step of delivering a message to a specific task associated with the stored timer. The method of claim 1, wherein if there is no software timer expired in the timer checking step, the number of lists is increased by one to check the next list, and the method returns to the list determining step. The method of claim 1, wherein the timer block is composed of two or more lists, wherein each list is configured so that a plurality of software timers can be connected in a fast order of expiration time. 4. The method according to any one of claims 1 to 3, wherein the software timer includes an ID of the timer, an expiration time, a job ID, a message buffer and connection information.