Need Programming help

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#1

We need help in programing autonomous mode. We need the program to continuously check the input from the sensors. How do I do that without having the whole program in a continuous loop?

#2

If you provide a bit more information, we could help you better.

What programming language are you using?
What sensors are you using?
What purpose are you using the sensors for?

#3

I’ll assume EasyC, since you didn’t say what programming tool you use.

“Timed driving” Autonomous example, is just a sequence of on/wait/off steps

//step1, raise arm for 1 second
 setmotor on;  // to raise the arm;
 wait(1000);   // wait 1
 setmotor off; // stop raising arm
// step2, drive forward for 2 seconds
 setmotor on; // drive forward
 wait(2000);  // wait 2
 setmotor off; //stop

To update “Timed driving” to sensor based, you can just replace each wait() with a while loop waiting on the sensor trigger
Instead of wait(1000) to raise the arm, check that the arm potentiometer is > 200.

while( getsensor(pot) < 200 ){ } // replacement for wait 1

while( wheel encoder < 374 ) { } // replacement for wait 2

Debugging productivity hint: use wireless download and insert print statements to show you what the sensors are reading;

#4

Thanks for your speedy answer!

We are using easy c v4. We are using quad shaft encoders for our two wheel drive and ultrasonic sensors to test the hight of our lifter. Is there a list of the different code for each sensor? Like

[INDENT]while( getsensor(pot) < 200 )
[/INDENT]

the part in the parentheses, is there a list of those things?

What is the word for limit switches, bump sensors, quad shaft encoders, ultrasonic sensors and light sensors?

Thanks!

#5

The word is “sensors”. In EasyCv4, Function block panel, there are a list of sensors in the “Inputs” section. There are also examples for how to use most of them in the Samples code directory.
var = GetAnalogInput( AnalogPort ); // is used for pot, light sensor, etc
Readability tip: Use program globals to #define Arm_Pot_port1 1
and #define Claw_pot_port2 2
and even #define Arm_up_limit 200
Then your code can look readable like this
while( (var1 = GetAnalogInput( Arm_pot_port1 ) ) < Arm_up_limit ) {
PrintToScreen( “Arm lift wait 1, armpot = %04d\n”, var1);
}
rather than this version that relies on comments to know the purpose.
while(( var1 = GetAnalogInput( 1) < 200){…}

Encoders and ultrasonics are more complicated because you need to start and preset them, but the GET part is similar.

#6

Ah, very helpful. Thanks. I have used global variables in C++ to make computer games, but I don’t know what their purpose is in easy C or how to apply them. I read a help file and couldn’t figure it out.

#7