HELP: analog input

[Tottanka]

the potentiometers are good like i said...
We have checked it with a voltmeter connecting between the where the white cable connects and where the red one connects and it shows the correct results.
We have also tried to change the ports, and neither of them worked...

[Alan Anderson]

Originally Posted by Tottanka

the potentiometers are good like i said...

If your idea of "good" does not match what the RC expects, it won't work no matter how many times you check to see that it's "good". In order to help you, we need to know exactly how you have wired it. Answering "we wired it correctly" is not going to help. For example:

We have checked it with a voltmeter connecting between the where the white cable connects and where the red one connects and it shows the correct results.

But where did you connect the black wire? What measurement are you making, and what results are you getting? Answering "the correct results" does not help.

A potentiometer on the Robot Controller's analog inputs needs three wires. Black (ground) goes to one end of the pot. Red (+5) goes to the other end of the pot. White (signal) goes to the wiper.

[Tottanka]

Like i said before...its connected CORRECTLY...
There is another problem...
Black goes to left side of potentiometer
Red goes to its right leg
and white goes to the middle one...
and they connect to the analog inputs correctly
We have measured voltages between red and white legs, and it shows inputs from 0 to 4.95V liniarically to the rotation i make...

Here's our code:
printf("%u",Get_Analog_Value(rc_ana_in01));

does not work with %d or %u....

could you show me the code of Get_Analog_value...perhaps the problem we have has to with that function...

[buddy.smith]

I don't know this first hand, but does the analog port need to be setup as an input somewhere? Does the ADC need to be enabled?

ttyl,

--buddy

[Shinigami2057]

Make sure you are calling the function

    Set_Number_of_Analog_Channels(SIXTEEN_ANALOG); /* DO NOT CHANGE! */

In User_Initialization(). Otherwise, I really don't know what to tell you. Make sure it's connected to the RC properly (wire ordering), there are no breaks in the PWM cable, that the wires are SECURELY (i.e. soldered) connected to the pot, and that you've tried it with all the analog inputs (well, 2-4 of them should probably suffice).

Good luck.

[Bharat Nain]

Okay, here is code from our robot this year. This is exactly how we have written it and it works.

We made variables on top of the file:

unsigned int BottomSonic = 0;

Then, inbetween Getdata and Putdata, we inserted these two lines:

Getdata(&rxdata);


TopSonic = Get_Analog_Value(rc_ana_in02);

printf("Top: %d\r\n", TopSonic);


Putdata(&txdata);

If you have it wired up correctly, then the code above will work.


Also, try it on a fresh piece of code with the absolute default code from IFI.

[FIRST JerseyKid]

Make sure your init functions are correct.

and call the get_analog_value()

[Alan Anderson]

Originally Posted by Tottanka

...and they connect to the analog inputs correctly...

You left out important details here. Please replace the word "correctly" with a description of the actual connection to the Robot Controller.

[EHaskins]

I have been having the exact same issue. I tried IFI's ADC, Kevin Watson's integrated into my code, Kevin Watson's from his website(unmodified), and whatever EasyC uses.

They all read 0.

I have tried both the 2006 and 2007 controllers.

I have the pot connected so the 5v+/gnd each connect to one side of the pot, and the signal is connected to the middle connector on the pot.

If I short the gnd/sig pins the reading does NOT change.

I have used Kevin Watson's ADC without any issues before now. I have run it on VEX, EDU, and 2005 controllers.

I was at the Sussex mini-regional today and talked to 4-5 other programmers, and none of them had any ideas.

What am I missing?

Thanks,
Eric Haskins