LEDSdriver configuration dialog This little program can be used to add some indication LEDs to your (media center) PC. It monitors several events and uses their status to drive the LEDs.

Since version 0.9.012 the LEDs can be controlled from the command line, scripts and 3rd party applications also.

LEDSdriver can control the LEDs on any PS/2 or USB keyboard, or up to 3 LEDs connected to a standard serial (COM) port. This makes it a simple job to mod the HDD LED of your HTPC into a recording LED.

The current version is capable of showing the following information:
- There are programs being recorded
- There is a media center extender in use
- The system is in Away Mode
- The system is resumed for a user task
- The system is resumed for an automatic task
- Several Media Center statuses like play, pause and mute
Suggestions for additional events are welcome (not necessarily media center related).

To me LEDSdriver has become one of my main debugging tools when it comes to resolving standby issues and the development of the MCE Standby Tool.

I picked the serial port because it's both software and hardware wise the most straight forward solution. The parallel port requires an additional device driver and USB ports need complex hardware components to drive a LED.

When there is no (free) serial port available just use a USB to serial converter to add one.

LEDSdriver should be compatible with every recent x86 and x64 Windows version starting from and including Windows 2000.

Visit the Slick Solutions sub-forum if you want to find out more on LEDSdriver.

Serial port hardware

A few very generic components and some basic soldering skills is all you need to connect the LEDs to the serial port. The LEDs have to be connected to DTR, RTS or TXD by a 1 Kilo Ohm resistor. Mind the polarity of the LED (the longest pin is the positive one).

The wiring should be done according one of the following diagrams:

A single LED connected to a serial port.

3 LEDs connected to a serial port.

A multi-color LED can be used to combine several functions into one LED.

A multi-color LED connected to a serial port.

Some motherboards do have an internal serial port connector. Be careful, there are at least two different versions of those. In case of doubt just let me know so I can check your motherboards manual. The following diagram shows how to connect LEDs to an internal connector on an ASUS, Gigabyte, MSI or Intel motherboard:

LEDs connected to an internal serial port header (ASUS/Gigabyte/MSI/Intel).

A serial port is able to drive 7 to 10mA, this is just enough for a generic LED. Using extra bright LEDs is not reccomended; they require more power and will not be able to reach full brightness.

Serial port direct connect (without soldering!)

For all of you without soldering skills I recently developed an option to connect the harddisk or power LED directly to an internal COM port header. There is no special hardware required. Check this thread for the details.


Since version 0.9.013 the keyboard LEDs are controlled by direct driver access, this will no longer influence the Num Lock, Caps Lock and Scroll Lock functions, only the LEDs. The screensaver, idle detection and monitor off functionality will also no longer be disturbed by LEDSdriver.

LEDSdriver is able to use a second (USB) keyboard and leave the primary keyboard for normal use.

Many wireless keyboard receivers that contain the LEDs make a perfect indication unit.

Controlling the LEDs from the command-line

Create event / LED relations based on the User events. Use the following command to change the state of the user events:

C:\Program Files\LEDSdriver\LEDSdriver.exe USEREVENTx=y

where x is the event number (0-2) and y is the state of the event (0 or 1).


Download and run the installer, follow the on-screen instructions. After the reboot a small green LED icon will show up in the task tray. Double-click this icon and select the LED device you want to use.


LEDSdriver is free for private use. In case you are building and/or selling media center PCs or parts for them on a commercial base and want to use LEDSdriver with them, want to use LEDSdriver for support- or other commercially related purposes please contact me for pricing and conditions.

2006-2010 Slick Solutions / Herman van Eijk