Matrix Orbital Corp

Posted: **Sat Jan 15, 2005 1:22 pm**

I want to use the three LED GPOs of this display with an RGB LED. For this I need to know how the LEDs are normally switched on or off by the GPOs. Does this happen by switching the + line on and off, or (like with, say the HDD LED and Power LED on the motherboard) by switching the - line on and off?

This will determine whether I need an RGB LED with common cathode or common anode. Can you advise?

Posted: **Mon Jan 17, 2005 9:50 am**

Hi Nexxo,

Thank you for posting at the lcd forums.

The GPOs share a common +5V, and other side is connected to seperate IO lines on the microcontroller. The LEDs turn on by switching the lines low, so you should get a LED with common anode.

If you have anymore questions or concerns, please feel free to contact me.

Best Regards,

Posted: **Mon Jan 17, 2005 1:24 pm**

Thank you very much!

Matrix Orbital Corp

Using RGB leds on the LED GPO of the LK202-24-USB

Using RGB leds on the LED GPO of the LK202-24-USB