This will not be a very useful tip for 99% of your arduino projects, but if you are wanting to keep your code running as quick as possible without reverting to C its a handy tip to have.
Ive got a few arduino projects going now where I need to keep my main loops running fast, This is a test to verify that a multiple IF statement finished if the primary statement is false.
In example... if(A= =false && B== true) the arduino will move onto the next line of code if stament A is not true. Restructuring your code a little to make sure you ask a boolean statement first can give you a little quicker loop times.
The results from the below test code:
Structure 1 :
24 (ms)
Structure 2 :
16 (ms)
Not a massive increase but something to keep in mind if you have resource expensive stamen conditions.
The Test Code:
| The Code |
|---|
/* Script to verify how the arduino habldes if routines with multiple statments. ABA test
28/8/2015 Michael Ratcliffe Mike@MichaelRatcliffe.com
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/>. */
//Just some variables for the test
long start=0; int i=0; int flag=1;
void setup() { // put your setup code here, to run once: Serial.begin(9600);
//Test A, a boolean comparison fisrt //runs loop 10,000 times and makes a log of time to compute if statment, shoot results out to terminal i=0; start=millis(); while (i<10000) { if(millis()%(6000)>10000000 && flag==0); i++; } Serial.println("Structure 1 : "); Serial.println(millis()-start);
//Test B, a heavier math based statment first i=0; start=millis(); while (i<10000) { if( flag==0 && millis()%(6000)>10000000 ); i++; } Serial.println("Structure 2 : "); Serial.println(millis()-start);
//Test A, a boolean comparison fisrt i=0; start=millis(); while (i<10000) { if(millis()%(6000)>10000000 && flag==0); i++; } Serial.println("Structure 1 : "); Serial.println(millis()-start);
}
void loop() { //We only need to run the test once }; |
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