ir sensor Board ??????????????????????

[Alan Anderson]

Originally Posted by Team2002

I was trying the following for our IR board and nothing seems to happen

if (rc_dig_in15 == 1)
{
    pwm_13 = 256;
}

This was just to test if pressing a button on the remote did anything (the remote was already programmed etc,.)

is there anything wrong that we are doing?

Yes. The valid range of values for a pwm output is 0-254. Since the pwm "variables" in the code are of type unsigned char, trying to set one to 256 will actually end up with it set to zero.

This snippet was placed in the user_routines.c
is that the correct place or should it be under user_routines_fast.c?

You'll need to be a lot more specific about where you put the code. The filename is not really important. What matters is the name of the function in which it appears: Process_Data_From_Master_uP(), Default_Routine(), Process_Data_From_Local_IO(), etc.

[AdmiralAllen]

Originally Posted by Alan Anderson

Yes. The valid range of values for a pwm output is 0-254. Since the pwm "variables" in the code are of type unsigned char, trying to set one to 256 will actually end up with it set to zero.



You'll need to be a lot more specific about where you put the code. The filename is not really important. What matters is the name of the function in which it appears: Process_Data_From_Master_uP(), Default_Routine(), Process_Data_From_Local_IO(), etc.

no......the maximum pwm value is 256......its an extrema

[Jon Stratis]

Originally Posted by AdmiralAllen

no......the maximum pwm value is 256......its an extrema

Actually, the maximum PWM value is 255, or 2^8 - 1, which is the maximum value that can be held in 8 bits of memory - the size of an unsigned char. Going above this will cause an overflow problem, where you'll loop around and start at 0 again.

[darkdwarven]

We were trying to find a way to program the Robot Cotroller so that when any of 2 inputs receive a signal, it will leave the autonomous code and enter a 'maual' autonomous code. The manual autonomous code would work based on 2 if statements that loop back to the other. The if statements would either say left or right and cotinue until our timer value ran out. Our code in the attached file, only makes the motors pulse for some other direction or go to one and continue straight without any further response. Any problems with our coding? Also does anyone know an easier way of accomplishing the same tasks?


Thanks always for the help,
Team 2348

[Team2002]

Originally Posted by Alan Anderson

Yes. The valid range of values for a pwm output is 0-254. Since the pwm "variables" in the code are of type unsigned char, trying to set one to 256 will actually end up with it set to zero.



You'll need to be a lot more specific about where you put the code. The filename is not really important. What matters is the name of the function in which it appears: Process_Data_From_Master_uP(), Default_Routine(), Process_Data_From_Local_IO(), etc.

I placed it under Default_Routine() is that the wrong place? I couldnt find a function called Process_Data_From_Local_IO(), in user_routines.c

[Alan Anderson]

Originally Posted by Team2002

I placed it under Default_Routine() is that the wrong place?

If your goal is to test the ability to use IR commands to control motors, that's probably the right place to put it.

But you need to make sure that the pwm outputs you set don't get set to something else later on. You can do that most easily by putting the IR sensing code near the end of the function, so it gets the last opportunity to force the motors to move as you want.