====== VGA to SCART ======
This pages describes a vga to scart adapter and a working setup with xFree/Xorg and old 80's style TV.
The ususal disclaimer and policy applys.

===== Hardware =====

==== Schematic ====


  VGA                                                SCART
  
   1 -O------------------------------------------O- 15 R
   2 -O------------------------------------------O- 11 G
   3 -O------------------------------------------O-  7 B
   
   6 -O------------------------------------------O- 13 R Gnd
   7 -O------------------------------------------O-  9 G Gnd
   8 -O------------------------------------------O-  5 B Gnd
   
   5 -O-+
        |
  11 -O-+
  
  Connector --------------------------------------O- 21 Connector
  shell                                                 shell
   
   14 -O------------------------+ 
  -VS                           |
                                |
                            |  /
          +-----+           |/
   13 -O--+ 3k3 +-----*-----|     BC 548 B
  -HS     +-----+     |     |\
                      |     |  \|
                      |        -|     +-----+
                      |         *-----+ 68  +-----O- 20
                      |         |     +-----+       -CS
                     +++       +++
                     | |       | |
                     | |       | |
                     +++       +++
                      |         |
   10 -O--------------*---------*-----------------O- 17
  Gnd                1k2       820                  Gnd
  
  
  *optional*: combine grounds
  
  5,6,7,8,Shell ------------------------------------ 5,9,13,17,21  (grounds)
  
  *optional*: hardcode TV mode - some //modern// TVs allow those modes 
  to be switched via OSD, or autodetection. I needed to hardwire those for my
  old 80's arcade - TV.
  
  +12V <------------------------*-----------------O- 8
                                |
                                |     +-----+
                                *-----+ 560 +-----O- 16
                                      +-----+       
  
  GND  <------------------------------------------O- 17,18


You can use any general purpose low frequent low power Si NPN transistor instead of the BC 548 B
The resistors are all standard 250 mW carbon film resistors;
   68 = 68 Ohm
  560 = 560 Ohm
  820 = 820 Ohm
  1k2 = 1200 Ohm
  3k3 = 3300 Ohm

Notes:

   * The link between 5 (Gnd) and 11 (Mid0) tells your VGA card that your `monitor' is colour.
   * The R-, G- and B grounds are in fact shields (The R-, G- and B wires are in fact little coaxes). The same goes for the `-CS' wire.
   * The connector shells are connected to a common shield screening all wires and coaxes inside the cable.
   * If you use a female SCART connector, use pin 19 for -CS. 

   * 12 Volt on scart pin 8 selects AV mode.
   * 3 Volt on pin 16 select RGB (instead of composite)

==== Testing and Debugging ====

===== Software =====


X11 //XF86Config-4// or  //xorg.conf//

  Section "Device"
        Identifier      "GFX"
  #     Driver          "mga"
        Driver          "nv"
        BusID           "PCI:1:5:0"
  EndSection

  Section "Monitor"
        Identifier      "TV"
        HorizSync       10-20
        VertRefresh     40-60
  
        ModeLine "TV" 18.00 936 968 1056 1152 576 580 583 625 interlace -hsync -vsync
  
  EndSection
  

==== nVidia RIVA 128(TM) ====

  minimum pixel clock of 18MHz.
  
==== Matrox MGA productiva G100 ====

  Clock range:  17.75 to 250.00 MHz

{{tag>video development installation}}