Datasheet

Make sure you're using the latest Trinket IDE so you can access pin #4's PWM capabilities. If you
aren't using the latest IDE you need to manually add functions like the following to init and write
analog values to pin #4. However if you have the latest IDE it includes fixes to make pin #4 usable
with Arduino's analogWrite function!
/*
Pulse
Pulses the internal LED to demonstrate the analogWrite function
This example code is in the public domain.
To upload to your Gemma or Trinket:
1) Select the proper board from the Tools->Board Menu
2) Select USBtinyISP from the Tools->Programmer
3) Plug in the Gemma/Trinket, make sure you see the green LED lit
4) For windows, install the USBtiny drivers
5) Press the button on the Gemma/Trinket - verify you see
the red LED pulse. This means it is ready to receive data
6) Click the upload button above within 10 seconds
*/
int led = 1; // pulse 'digital' pin 1 - AKA the built in red LED
// the setup routine runs once when you press reset:
void setup() {
// initialize the digital pin as an output.
pinMode(led, OUTPUT);
}
// the loop routine runs over and over again forever:
void loop() {
for (int i=0; i<256; i++) {
analogWrite(led, i); // PWM the LED from 0 to 255 (max)
delay(5);
}
for (int i=255; i>=0; i--) {
analogWrite(led, i); // PWM the LED from 255 (max) to 0
delay(5);
}
}
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