5 replies to this topic

[Paulo Jardim]

I dont know if is a board problem but all digital pins show about 3.23V.... i conected a led in the Pin D1 and in GND and the led is aways on but with a weak lights. CODE: private OutputPort led = new OutputPort(Pins.ONBOARD_LED, false); motor.Write(true); Thread.Sleep(10000); motor.Write(false); motor.Dispose(); when motor is true the voltage go to 3.3V and led lights strong. I dont know what happned but look like only the tension change and not the voltage.

[Stefan]

Hi, How did you declare the variable 'motor'? By default, pullup resistors are enabled on each pin, which caused the readings.

[Paulo Jardim]

OutputPort motor = new OutputPort(Pins.GPIO_PIN_D1, false);

[Chris Walker]

Hi Paulo, When Netduino first boots, all of its pins are in "input, pullup" state. This will provide a weak current (at 3.3V) which may cause your LEDs to light up very weakly. When you create an OutputPort as set it to True, that will drive current. If you are setting the OutputPort to False and still have voltage on the pin, that shouldn't happen. If that's the case, please create a simple project (4-5 lines of code) and post the full code sample here so we can help take a look. Chris

[Paulo Jardim]

Hi Paulo,

When Netduino first boots, all of its pins are in "input, pullup" state. This will provide a weak current (at 3.3V) which may cause your LEDs to light up very weakly. When you create an OutputPort as set it to True, that will drive current.

If you are setting the OutputPort to False and still have voltage on the pin, that shouldn't happen. If that's the case, please create a simple project (4-5 lines of code) and post the full code sample here so we can help take a look.

Chris

Chiris all digital pins has about 3.23 Voltage.

I tryed sent the fallow code to board:

OutputPort motor = new OutputPort(Pins.GPIO_PIN_D1, false);

motor.Write(true);
Thread.Sleep(10000);
motor.Write(false);
motor.Dispose();

but aways all pins show me 2.23v in low and when motor is on voltage go to 3.3v and led lights strong.

when motor is of voltage from pin 1 go to 2.3V.

Looks lime only tension change....not voltage....

[Geancarlo2]

Hi Paulo, can you post what circuit are you using? Do you have an appropriate resistor between the port and the led? P.S.: "Tension" is voltage, they are interchangeable terms in portuguese, although "voltagem" isn't well accepted among professionals...