We do not have any change in the speed in the Tetrix standard DC 12V motors although we seem to be editing it. Here is our code. When we plugged in the Lego NXT motors, we did get speed variablity.

#pragma config(Hubs, S1, HTMotor, HTServo, none, none)
#pragma config(Motor, mtr_S1_C1_1, motorD, tmotorNormal, PIDControl)
#pragma config(Motor, mtr_S1_C1_2, motorE, tmotorNormal, PIDControl)
//*!!Code automatically generated by 'ROBOTC' configuration wizard !!*//

#include "JoystickDriver.c"

task main()
{
while (true)
{
getJoystickSettings(joystick);

motor[motorD] = 100;

}
}

Just something as simple as this, without any joystick input, does not change at all when it is run. When we do add in the joysticks, there is no speed variabilty as well.
Thanks!

-Francis Parker WARLORDS

Do you have the shaft encoders installed? If not, turn off PID control. What is probably happening is:

- You are asking for a particular speed
- The controller applies power to the motor
- There is no data coming from the shaft encoder which it interprets as the motor being stopped
- The controller applies more power to the motor to try to get it moving
- Round and round until (more or less) full power is being applied.

How do we install shaft encoders and what exactly are they?

-Francis Parker WARLORDS

They look like the attached picture. Your kit should have come with two of them and with instructions for assembling them.



Note: BE VERY CAREFUL. Even with the FTC Team 20% discount they cost about $64 each.