EDID - Extended Display Identification Data     and     DDC - Display Data Channel

See:   DVI   HDMI    HDCP   AACS



EDID- Extended Display Identification Data are data that are sent from a connected DVI receiver to the DVI transmitter during the boot process. It is a standard VESA format allowing a monitor to communicate its own basic information to a computer etc.

(Horizontal Pixel, Vertical Lines, Horizontal and Vertical Sync Frequency, Dot Clock, Horizontal and Vertical Blanking and maximum image size, color characteristics, factory pre-set timings, frequency range limits, and character strings for the monitor name and serial number.)



See an EDID table from http://www.jvcdig.com.

The EDID information is the critical issue for DVI matrices because the transmitter and the receiver must be connected during the boot process to exchange the proper information.
The EDID information is transmitted over the DDC (Display Data Channel) on pin 6 and 7 on the DVI connector (see DVI Connector).

Typical EDID data:

> --- EDID Information for display device DFP-0 ---
> Manufacturer: GSM Model: 101 Serial#: 34596322
> Year: 2004 Week: 3
> EDID Version: 1.3
> Digital Display Input
> Max H-Image Size [cm]: horiz.: 71 vert.: 40
> Gamma: 2.20
> No DPMS capabilities specified; RGB/Color Display
> First detailed timing is preferred mode
> redX: 0.640 redY: 0.340 greenX: 0.300 greenY: 0.690
> blueX: 0.138 blueY: 0.038 whiteX: 0.270 whiteY: 0.365
> Manufacturer's mask: 0
> Supported additional Video Mode:
> clock: 74.2 MHz Image Size: 708 x 398 mm
> h_active: 1920 h_sync: 2008 h_sync_end 2052 h_blank_end 2200 h_border: 0
> v_active: 540 v_sync: 542 v_sync_end 547 v_blanking: 562 v_border: 0
> Supported additional Video Mode:
> clock: 27.0 MHz Image Size: 708 x 398 mm
> h_active: 720 h_sync: 736 h_sync_end 798 h_blank_end 858 h_border: 0
> v_active: 480 v_sync: 489 v_sync_end 495 v_blanking: 525 v_border: 0
> Ranges: V min: 59 V max: 60 Hz, H min: 31 H max: 45 kHz, PixClock max 80 MHz
> Monitor name: C32V37
> --- End of EDID Information for display device DFP-0 ---

In most source devices (PC, HD Receiver etc.) the incoming EDID information from the monitor or display can be set to be ignored. In certain cases of incompatibilities this can be advisable.

-- But graphic cards and monitors can also be destroyed by using the wrong settings ! --

There are programs out there to read the EDID information from a monitor: READ-EDID

In comparison to the EDID information, modelines are part of a configuration file in the connected computer how to drive at a specified display resolution. Modelines can be edited manually or with certain software.
Typical Modeline: "1280x960@96" = 165.88 1280 1336 1616 1728 960 962 974 1000

Online Modeline Calculator