555 timer motor shield

I have the 555 timers set up in bistable mode with an out put to a servo, but a 555 timers input in bistable mode is - and an output from arduino is +, so I need a not gate. but I dont have one how can I make one,
thanks

Unless there is something very odd about you circuit you don't drive it -ve you drive it low to trigger the 555.

So connect the pin of the Arduino to the trigger of the 555 and use digitalWrite(pin,LOW) to set the 555 running and digitalWrite(pin,HIGH) to stop it.

Mark

And anyhow, the way I understand things, a not gate would not make a +ve signal -ve, it would make it 0.

In a Boolean world, NOT(1) is 0, not -1.

Not so? 8)