CommonPIC32

docs/wiki/VGA_Signal_Wiring

154:c8a37eb47211
2021-12-14 Paul Boddie Fixed pin labels: RB10/PGEC3 should be RB10/PGED2.
     1 = VGA Signal Wiring =     2      3 The generation of a VGA-compatible video signal from a PIC32 microcontroller     4 is demonstrated by a number of [[VGA Output Examples|examples]]. Common to     5 these are certain hardware characteristics, described here to avoid     6 unnecessary repetition.     7      8 == Data Signal Routing ==     9     10 The following routing from output pins to output socket pins is employed.    11     12 {{{#!graphviz    13 //format=svg    14 //transform=notugly    15 digraph routing {    16   graph [ranksep=1.0,style=invis,fontsize="15.0",fontname="sans-serif",splines=ortho];    17   node [shape=box,style=filled,fillcolor=white,fontsize="13.0",fontname="sans-serif"];    18   rankdir=LR;    19     20   /* Output pins. */    21     22   subgraph {    23     rank=same;    24     pins [label="Output pins",shape=note,fillcolor=gold];    25     D6 [fillcolor=lightgrey];    26     D5 [fillcolor="#ff7777"];    27     D4 [fillcolor="#ff7777"];    28     D3 [fillcolor="#77ff77"];    29     D2 [fillcolor="#77ff77"];    30     D1 [fillcolor="#7777ff"];    31     D0 [fillcolor="#7777ff"];    32     D7 -> D6 -> D5 -> D4 -> D3 -> D2 -> D1 -> D0 -> HSYNC -> VSYNC -> pins [style=invis];    33   }    34     35   /* Intensity adjustment resistor. */    36     37   I2 [label="2200R"];    38     39   /* Colour channel resistors and diodes. */    40     41   subgraph {    42     rank=same;    43     R2 [label="470R",fillcolor="#ff7777"];    44     R1 [label="1000R",fillcolor="#ff7777"];    45     RD [label="diode",fillcolor="#ff7777"];    46     R2 -> R1 -> RD [style=invis];    47   }    48     49   subgraph {    50     rank=same;    51     G2 [label="470R",fillcolor="#77ff77"];    52     G1 [label="1000R",fillcolor="#77ff77"];    53     GD [label="diode",fillcolor="#77ff77"];    54     G2 -> G1 -> GD [style=invis];    55   }    56     57   subgraph {    58     rank=same;    59     B2 [label="470R",fillcolor="#7777ff"];    60     B1 [label="1000R",fillcolor="#7777ff"];    61     BD [label="diode",fillcolor="#7777ff"];    62     B2 -> B1 -> BD [style=invis];    63   }    64     65   /* Video signals. */    66     67   subgraph {    68     rank=same;    69     signals [label="Video signals",shape=note,fillcolor=gold];    70     R [fillcolor="#ff7777"];    71     G [fillcolor="#77ff77"];    72     B [fillcolor="#7777ff"];    73     R -> G -> B -> HS -> VS -> signals [style=invis];    74   }    75     76   D7 -> I2;    77   D6 /* not connected */    78   D5 -> R2 -> R;    79   D4 -> R1 -> R;    80   D3 -> G2 -> G;    81   D2 -> G1 -> G;    82   D1 -> B2 -> B;    83   D0 -> B1 -> B;    84     85   I2 -> RD;    86   I2 -> GD;    87   I2 -> BD;    88     89   RD -> R;    90   GD -> G;    91   BD -> B;    92     93   HSYNC -> HS;    94   VSYNC -> VS;    95 }    96 }}}    97     98 Where two bits of intensity are supported, D6 is routed via a 4700 ohm    99 resistor to each of the colour channel diodes, contributing to the existing   100 D7-driven intensity signal.   101    102 == Pinouts ==   103    104 For the examples documented in this project, the following pinouts apply. VGA   105 connectors also support other signals, generally used for querying a display   106 for supported resolutions, but since a statically configured resolution is   107 employed by these examples, these other signals are left unconnected.   108    109 === Output Socket Pinout ===   110    111 {{{   112 5 (GND)  4 (NC)   3 (B)    2 (G)    1 (R)   113    114     10 (GND) 9 (NC)   8 (GND)  7 (GND)  6 (GND)   115    116 15 (NC)  14 (VS)  13 (HS)  12 (NC)  11 (NC)   117 }}}   118    119 === Output Cable Pinout ===   120    121 {{{   122     1 (R)    2 (G)    3 (B)    4 (NC)   5 (GND)   123    124 6 (GND)  7 (GND)  8 (GND)  9 (NC)   10 (GND)   125    126     11 (NC)  12 (NC)  13 (HS)  14 (VS)  15 (NC)   127 }}}   128    129 === References ===   130    131  * [[WikiPedia:VGA connector]]   132    133  * [[http://papilio.cc/index.php?n=Papilio.VGAWing|VGAWing]]   134    135  * [[http://lucidscience.com/pro-vga%20video%20generator-2.aspx|   136      LucidScience - Build the VGA VIDEO GENERATOR - Page 2 of 16]]   137    138  * [[https://sites.google.com/site/h2obsession/CBM/C128/rgbi-to-vga|   139      RGBI to VGA - H2Obsession]]