Motor doesn't want to work

Using Arduino Project Guidance
#1

Hey guys-

I have a Tamiya twin motor gearbox, and I know the motor works. When hooking one lead to ground, and one to the +5V pin on the Arduino Uno, it runs just fine.

However, if I try to run it off a single pin, say, Pin 8, nothing happens.

All my code does is set Pin 8 to be high, but the motor won’t spin.

void setup()  { 
  pinMode(8,OUTPUT); 
  } 

void loop()  {
digitalWrite(8, HIGH);  
}

Can the Arduino pins not provide the current required to spin the motor?

#2

you could drive a transistor with your pin 8 that switches a separate power source.

#3

So the arduino pins can't provide the current?

#4

However, if I try to run it off a single pin, say, Pin 8, nothing happens.

The arduino pins can only supply 40ma max. Trying to run a motor off of an arduino pin is somewhat like trying to start your car with a watch battery.

#5

Definitely not...you need a "motor driver" to provide bidirectional control over the motor or just a transistor switch for single-direction control.

Start with the "Physical/Mechanical" section of the Playground for some learning links:

http://www.arduino.cc/playground/Main/InterfacingWithHardware#Physical_Mechanical

-- The Rugged Motor Driver: two H-bridges, more power than an L298, fully protected

#6

Alright, thanks.

I have an Ardumoto Motor Driver Shield from Sparkfun, I've just never used it.

I guess I'll be needing to go to Frys this weekend and pickup some pin headers and the like though.

Thanks for the help again.

#7

Be aware that you might actually have damaged your Arduino or the pin you used for driving the motor.

You should test it with a LED and suitable current limiting resistor to make sure it still works as expected.

#8