dimmer sample sketch

Forum 2005-2010 (read only) Software Interfacing
1

A point in the right direction would be very helpful.

I am am using a arduino duemilanove with an atmega 328 with a windows xp pc and am trying to get the dimmer example sketch to run. I have put the code that comes with the sketch into processing, and the led will not light, with the arduino and processing running the sketch. The arduino is in com5. I literally just got my arduino yesterday, and have only a small knowledge of the programming language. does anyone have supplemental information which will help me run this program, and pleas let me know if you need any other information.

2

How have you wired up the LED? Are you using the same pin that the software is expecting to use? Have you used a resistor in series with the LED?

Can you post a link to the sketch you are trying to run?

3

code that comes with the sketch into processing

Are you using the Arduino IDE? If so, which version?

4

I have checked the led placement several times, and the led needs no resistor because it can run the 5v from the usb supply. The arduino environment I use is the current 0015.
The sketch can be found here:

5

Are you able to successfully upload the sketch to the Arduino? Or do you get an error message when uploading?

6

the led needs no resistor because it can run the 5v from the usb supply.

NO NO NO. An LED always needs a resistor and there is one shown in the circuit in the link you posted.

Test to see if you have the LED the right way round by disconnecting the resistor going to pin 9 and putting it in the 5v hole on the other side of the board (with the other side of the LED still connected to ground). The LED should then light up. If it doesn't then swap over the pin 9 and ground connections. That is connect the LED / resistor combination the other way round.

7

There is no error message in the software, and I will go put in a resistor.
Could the problem be with the processing code?

8

There is no error message in the software,

That doesn't mean there is nothing wrong with the code it only means the syntax is fine.

After you have done the test above, write a blinking light sketch based on the pin you are using, because driving an LED without a resistor could have blown your output pin.

9

@ everyone:
or just change pin 9 to pin13, it saves more time =D

10

@ everyone:
or just change pin 9 to pin13, it saves more time =D

A good idea, although you might want to read here: http://arduino.cc/en/Reference/AnalogWrite
And notice the:

...with the ATmega168 chip, this function works on pins 3, 5, 6, 9, 10, and 11.

And thus, not on pin 13 :wink:

11

I put in a resistor and followed the correct instructions, which I hadn't done before, and it works now.
Thank You! ;D