EDID Basics

EDID is an acronym for Extended Display Information Data.  EDID was originally implemented by computer monitors with DVI inputs to present its display capabilities to a video card so a compatible video resolution could be ouput  to the attached monitor. EDID is also used by HD Displays via HDMI to identify the HDTV display and audio capabilities to consumer video sources.

EDID is programmed by Display manufactures to specify model , manufacturing date and the Display capabilities such as resolution support, and audio capability. A rudimentary example of a EDID is shown below:

EDID from Samsung LED TV

The Raw EDID shown is read by the source player and is interpreted as: ” I am a Samsung LED tv, I am capable of displaying 3D video and 1080P video resolution. My audio capabilities are 2 ch PCM only .” Once the EDID is read by the video source, the video source can be configured so the source will not send video or audio that exceeds the capability of the attached display.

EDID typically include 256 byte of data and stored in a PROM inside the display and communicates to the the video source via I2C bus. One can use a EDID reader such as Monitor Asset Manager from ENTECH to view a display’s EDID.

More info at: www.octavainc.com

 

 

 

 

Simple Infrared IR Remote Control testing with a Digital Camera

Remote controls are ubiquitous and are reliable method for controlling Audio video equipment.  However some common problems encountered with remote controls are:1) low battery levels 2)  remote code  has been “reset” or deleted  and 3) IR diode in remote damaged. This article will provide a simple troubleshooting method to find the cause of the problem.

Vast majority of remote controls for consumer grade Audio Video equipment use IR. IR remote controls transmit IR via a diode in the 940nm wavelength. IR spectrum is above the visible light spectrum, therefore IR can not be seen by the naked eye. However the CCD detectors in most digital cameras or smartphones are sensitive to IR and can be used to determine if a remote control is operational.

Using Digital Camera to test IR of Remote Controls:

  1. Set your digital camera or smartphone to view mode
  2. Point the front of the Remote Control at the camera lens
  3. Press and hold down  a button on the remote. You will see a blue light on the camera view screen if the remote control IR diode is operating.

Diagnosis:

  • No IR is detected by camera: change battery on the remote. If changing battery does not solve it, then the remote control is damaged.
  • IR is detected by camera: If you are using a Universal /multi-device remote, most likely your programmed codes has been “reset”. Try re-programming the device codes to the remote control.

More info can be found at : www.octavainc.com