Posts: 2
Registered: ‎09-29-2014

Leds on si4455


I wanted to know if there is any way to modify the way that the led lights up. 

Here is an exemple of what I wanted to try

Thank you! 

Posts: 72
Registered: ‎02-18-2014

Re: Leds on si4455

Hi Enger,


In our sample codes we just toggle the GPIO pins to turn ON/OFF the LEDs. It is certainly possible to implement fading, but you need to make some modifications on the code. When driving an LED in PWM (Pulse Width Modulation) mode, you can adjust the brightness of the LED. Essentially you are turning ON and OFF the LED so quickly that you are seeing it continuously being ON. As you change the duty cycle you adjust the brightness: The longer the ON pulses are the brighter it is. You can use either a built-in MCU HW timer, or just a SW counter for the PWM timing.


On the RFStick platform it is fairly simple as the LEDs are directly connected to the host MCU, but on the WMB930 the LED driving pins are shared with the pushbutton input pins, so it would be somewhat more complex.