How to calculate the time deadlines for a given task ?

Tigerly · April 2, 2018, 9:43pm

I’m a beginner of the ardupilot. When I check the source code (arducopter.cpp), I found there are several maximum time here:

github.com

ArduPilot/ardupilot/blob/master/ArduCopter/ArduCopter.cpp

/*
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
/*
 *  ArduCopter (also known as APM, APM:Copter or just Copter)
 *  Wiki:           copter.ardupilot.org
 *  Creator:        Jason Short
 *  Lead Developer: Randy Mackay
 *  Lead Tester:    Marco Robustini

This file has been truncated. show original

/*
scheduler table for fast CPUs - all regular tasks apart from the fast_loop()
should be listed here, along with how often they should be called (in hz)
and the maximum time they are expected to take (in microseconds)
*/
const AP_Scheduler::Task Copter::scheduler_tasks[] = {
SCHED_TASK(rc_loop, 100, 130),
…

My questions are:

how do you calculate these time deadlines?
Is there any way that I can calculate such time deadline of a given function/task?

Thanks in advance!

Tigerly · May 9, 2018, 3:51pm

any idea about this question?