오전 1:02 2008-11-12
EGA와 VGA 그리고 LCD
bro@shinbiro.com 조경민
=====================================================================
구현 방법
--------------------------------------------------------------
보드 상 VGA (RGB신호 핀) --> wire wrap ---> 330 ohm --> D-Sub 15F (connector) ---> VGA cable ---> LCD Monitor
DSub 3열 15 pin female DIP 타입 410원 근데 DIP핀도 3열이네;
DIP 핀을 wrap board
http://www.eleparts.co.kr/shop/view.php?cate1=45&cate2=288&cate3=529&cate4=&item=3495&keyword=&page=1
DIP핀에 wire wrap하고
330 ohm (resistor)을 R, G, B 선에 연결 한 후 VGA connector에 연결
http://www.stevechamberlin.com/cpu/2008/06/24/video-tests/#comments
http://www.monitor4u.co.kr/guide/content/?idx=179&page=3&page_col=3&act=view
EGA
----------------------------------------------------------------
디지털
http://en.wikipedia.org/wiki/Enhanced_Graphics_Adapter
640x350x16c, other mode
H-freq 15.7/21.8kHz
V-freq 60Hz
color 16/64
핀 9개
1. GND
2. SR: Secondary Red (intensity)
3. PR: Primary Red
4. PG: Primary Green
5. PB: Primary Blue
6. SG: Secondary Green (intensity)
7. SB: Secondary Blue (Intensity)
8. H : Horizontal Sync
9. V : Vertical Sync
VGA
---------------------------------------
1987 IBM
D-Sub 아날로그
256 KB Video RAM
16-color and 256-color modes
262,144-value color palette (six bits each for red, green, and blue)
Selectable 25.175 MHz [3] or 28.322 MHz master clock
Maximum of 800 horizontal pixels[4]
Maximum of 600 lines[5]
Refresh rates at up to 70 Hz [6]
Vertical Blanking interrupt (Not all clone cards support this.)
Planar mode: up to 16 colors (4 bit planes)
Packed-pixel mode: 256 colors (Mode 13h)
Hardware smooth scrolling support
Some "Raster Ops" support
Barrel shifter
Split screen support
0.7 V peak-to-peak [7]
75 ohm double-terminated impedance (18.7mA - 13mW)
텍스트 모드와 아래 표준 그래픽 모드
640×480 in 16 colors
640×350 in 16 colors
320×200 in 16 colors
320×200 in 256 colors (Mode 13h)
핀 정보
D-Sub 15 Pin 아래와 같이 배열
--------------------
5 4 3 2 1
10 9 8 7 6
15 14 13 12 11
--------------------
Video signal RGB video signal plus option H and V sync
Data signal I²C data channel for DDC information
Connector DE-15
Pin 1 RED Red video
Pin 2 GREEN Green video
Pin 3 BLUE Blue video
Pin 4 N/C Not connected
Pin 5 GND Ground (HSync)
Pin 6 RED_RTN Red return
Pin 7 GREEN_RTN Green return
Pin 8 BLUE_RTN Blue return
Pin 9 +5 V +5 V DC
Pin 10 GND Ground (VSync, DDC)
Pin 11 N/C Not connected
Pin 12 SDA I²C data
Pin 13 HSync Horizontal sync
Pin 14 VSync Vertical sync
Pin 15 SCL I²C clock
VGA 시스템 (그래픽 카드) 구현
---------------------------------------------------------------------------------
모니터 연결하려면 analog VGA 15pin을 연결하면된다.
HSync와 VSync를 원하는 간격으로 생성해서 그 안에 픽셀 정보를 잘 넣으면 화면에 뿌려짐
Rx인 모니터는 HSync, VSync가 발생되는 간격을 통해서 해당 해상도를 자동으로 파악함.
640x480동작시키려면 25.175 MHz 오실레이터 필요.
640 + 160 (HBLANK 구간) 합쳐서 라인 당 800 픽셀
25.175MHz which is about 39.72 ns
http://www.epanorama.net/documents/pc/VGA_timing.html
http://en.wikipedia.org/wiki/VGA
http://ko.wikipedia.org/wiki/VGA
palette controller
UM70C171 Color Palette with Triple 6-bit DAC
256x18bit color palette RGB analog Output 24 DIP pin
http://doc.chipfind.ru/umc/um70c171.htm
25.175MHz OSC (for VGA)
256K SRAM (for VIDEO RAM)
http://www.stevechamberlin.com/cpu/2008/07/20/video-system-design/
http://www.stevechamberlin.com/cpu/2008/02/26/peripherals-galore/
http://www.stevechamberlin.com/cpu/2008/06/29/video-notes/
http://www.hanssummers.com/computers/newz80/circuit/index.htm
멀티 싱크 모니터
---------------------------------------------------------------------------
http://www.encyber.com/search_w/ctdetail.php?masterno=792291&contentno=792291
멀티싱크로너스 모니터(multi synchronous monitor)라고도 한다. 1985년 일본 NEC사에서 개발한 것으로 입력 신호 주파수가 고정되어 있지 않은 모니터를 말한다.
초기 모니터들은 모두 멀티모드모니터(multi mode monitor)로서 고정된 주파수만을 지원하였기 때문에 규격이 일치하는 비디오카드만을 사용해야 했다. 그러나 그래픽 환경이 점점 발달하면서 고해상도를 표현할 수 있도록 다양한 주파수를 지원할 수 있는 멀티싱크모니터가 개발되었다.
멀티싱크모니터는 주파수가 고정되어 있지 않으므로 다양한 주파수대의 여러 종류의 그래픽카드를 사용할 수 있다. 예를 들어 EGA(ehanced graphics adapter) 그래픽카드를 사용하면 EGA 모니터로 동작하고, VGA(video graphics adapter) 그래픽카드를 사용하면 VGA 모니터로 동작한다.
그러므로 어떤 그래픽카드를 사용하더라도 흑백모니터, CGA(color graphics adapter) 모니터, EGA 모니터, VGA 모니터 등의 모든 모니터 기능을 할 수 있다. 최근에 사용되는 모니터들은 모두 멀티싱크모니터이다.
http://dojeun.egloos.com/320922
VGA video signal generation
-------------------------------------------------------------
http://lslwww.epfl.ch/pages/teaching/cours_lsl/ca_es/VGA.pdf
HSYNC, VSYNC 발생 타이밍은 다음과 같다.
HSYNC
___________________ _________
|____|
<------------->
640
<------------------>
660
<----------------------->
756
<--------------------------------> h_count
800
VSYNC
___________________ _________
|____|
<------------->
480
<------------------>
494
<----------------------->
495
<--------------------------------> v_count
525
VGA timing information
--------------------------------------------------------
http://www.epanorama.net/documents/pc/vga_timing.html
Horizonal Timing
Horizonal Dots 640 640 640
Vertical Scan Lines 350 400 480
Horiz. Sync Polarity POS NEG NEG
A (us) 31.77 31.77 31.77 Scanline time
B (us) 3.77 3.77 3.77 Sync pulse lenght
C (us) 1.89 1.89 1.89 Back porch
D (us) 25.17 25.17 25.17 Active video time
E (us) 0.94 0.94 0.94 Front porch
______________________ ________
________| VIDEO |________| VIDEO (next line)
|-C-|----------D-----------|-E-|
__ ______________________________ ___________
|_| |_|
|B|
|---------------A----------------|
Vertical Timing
Horizonal Dots 640 640 640
Vertical Scan Lines 350 400 480
Vert. Sync Polarity NEG POS NEG
Vertical Frequency 70Hz 70Hz 60Hz
O (ms) 14.27 14.27 16.68 Total frame time
P (ms) 0.06 0.06 0.06 Sync length
Q (ms) 1.88 1.08 1.02 Back porch
R (ms) 11.13 12.72 15.25 Active video time
S (ms) 1.2 0.41 0.35 Front porch
______________________ ________
________| VIDEO |________| VIDEO (next frame)
|-Q-|----------R-----------|-S-|
__ ______________________________ ___________
|_| |_|
|P|
|---------------O----------------|
http://www.intrinsix.com/intrinsix-ip/vga/vga-core.htm
Mode | Type | Res. | Colors | Vert. | Horz. | Pix Clk |
SM and SXGA MODES | ||||||
0, 1 | A/N | 320 x 200 | 16 | 70 Hz | 31.778 KHz | 25.175 MHz |
2, 3 | A/N | 640 x 200 | 16 | 70 Hz | 31.778 KHz | 25.175 MHz |
0*, 1* | A/N | 320 x 350 | 16 | 70 Hz | 31.778 KHz | 25.175 MHz |
2*, 3* | A/N | 640 x 350 | 16 | 70 Hz | 31.778 KHz | 25.175 MHz |
0+, 1+ | A/N | 320 x 350 | 16 | 70 Hz | 31.778 KHz | 28.322 MHz |
2+, 3+ | A/N | 640 x 350 | 16 | 70 Hz | 31.778 KHz | 28.322 MHz |
4, 5 | APA | 320 x 200 | 4 | 70 Hz | 31.778 KHz | 25.175 MHz |
6 | APA | 640 x 200 | 2 | 70 Hz | 31.778 KHz | 25.175 MHz |
7 | A/N | 720 x 350 | Mono | 70 Hz | 31.778 KHz | 28.322 MHz |
7+ | A/N | 720 x 400 | Mono | 70 Hz | 31.778 KHz | 28.322 MHz |
D | APA | 320 x 200 | 16 | 70 Hz | 31.778 KHz | 25.175 MHz |
E | APA | 640 x 200 | 16 | 70 Hz | 31.778 KHz | 25.175 MHz |
F | APA | 640 x 350 | Mono | 70 Hz | 31.778 KHz | 25.175 MHz |
10 | APA | 640 x 350 | 16 | 70 Hz | 31.778 KHz | 25.175 MHz |
11 | APA | 640 x 480 | 2 | 60Hz | 31.778 KHz | 25.175 MHz |
12 | APA | 640 x 480 | 16 | 60Hz | 31.778 KHz | 25.175 MHz |
13 | APA | 320 x 200 | 256 | 70 Hz | 31.778 KHz | 25.175 MHz |
SXGA MODES | ||||||
101 | APA | 640x480 | 256 | 85 Hz | 43.3 KHz | 36.00 MHz |
102 | APA | 800 x 600 | 16 | 85 Hz | 53.7 KHz | 56.25 MHz |
103 | APA | 800 x 600 | 256 | 85 Hz | 53.7 KHz | 56.25 MHz |
104 | APA | 1024 x 768 | 16 | 85 Hz | 68.7 KHz | 94.5 MHz |
105 | APA | 1024 x 768 | 256 | 85 Hz | 68.7 KHz | 94.5 MHz |
106 | APA | 1280 x 1024 | 16 | 85 Hz | 91.1 KHz | 157.5 MHz |
107 | APA | 1280 x 1024 | 256 | 85 Hz | 91.1 KHz | 157.5 MHz |
114 | APA | 800 x 600 | 64K | 85 Hz | 53.7 KHz | 56.25 MHz |
115 | APA | 800 x 600 | 16.8 M | 85 Hz | 53.7 KHz | 56.25 MHz |
117 | APA | 1024 x 768 | 64K | 85 Hz | 68.7 KHz | 94.5 MHz |
118 | APA | 1024 x 768 | 16.8 M | 85 Hz | 68.7 KHz | 94.5 MHz |
11A | APA | 1280 x 1024 | 64K | 85 Hz | 91.1 KHz | 157.5 MHz |
11B | APA | 1280 x 1024 | 16.8 M | 85 Hz | 91.1 KHz | 157.5 MHz |
text mode verilog source
http://web.mit.edu/6.111/www/f2005/code/labkit_beta2demo/vga.v.html
여러 그래픽 카드에 대한 정보
------------------------------------------------------------
http://stason.org/TULARC/pc/video-faq/index.html
http://stason.org/TULARC/pc/video-faq/62-What-is-VGA-and-how-does-it-work.html
Graphics Controller: Can perform logical functions on data being written to display memory.
Display Memory: A bank of 256k DRAM divided into 4 64k colour planes. It is used to store screen display data.
Serializer: Takes display data from the display memory and converts it to a serial bitstream which is sent to the attribute controller.
Attribute Controller: Contains the colour LUT (Look Up Table) which determines what colour will be displayed for a given pixel value in display memory.
Sequencer: Controls timing of the board and enables/disables colour planes.
CRT Controller: Generates syncing and blanking signals to control the monitor display.
The VGA modes are:
Mode Type Resolution Chars Colours
(Hex)
0,1 text 360x400 40x25 16
2,3 text 720x400 80x25 16
4,5 gfx 320x200 40x25 4
6 gfx 640x200 80x25 2
7 text 720x400 80x25 mono
D gfx 320x200 40x25 16
E gfx 640x200 80x25 16
F gfx 640x350 80x25 mono
10 gfx 640x350 80x25 16
11 gfx 640x480 80x30 2
12 gfx 640x480 80x30 16
13 gfx 320x200 40x25 256
대부분의 PC모니터는 다음 MDA/Hercules/CGA/EGA 모드를 지원
Display Compatible Colours Text Graphics Scan
Adapters Res. Resolution Rates
----------------------------------------------------------------------
Monochrome MDA 640x350 Vert-50 Hz
Hercules 2 80x25 720x350 Hor-18.43 kHz
EGA 720x348
----------------------------------------------------------------------
Color CGA 16 40x25 320x200 V-60 Hz
EGA 80x25 640x200 H-18.43 kHz
----------------------------------------------------------------------
Enhanced CGA 16 of 40x25 320x200 V-60 Hz
Color EGA 64 80x25 640x200 H-18.43 kHz
640x350 or 21.8 kHz
----------------------------------------------------------------------
Multisync CGA 16 of 40x25 320x200 Variable
digital EGA 64 80x25 640x200
640x350
----------------------------------------------------------------------
Multisync VGA 256 of 80x25 640x480 Variable
analog 256k 800x600
----------------------------------------------------------------------
VGA Color VGA 256 of 40x25 320x400 V-70 Hz
display 256k 80x25 640x400 H-31.5 kHz
VGA Mono 320x350
display 640x350
720x350
720x400
640x480
----------------------------------------------------------------------
20 How do I calculate the minimum bandwidth required for a monitor?
Bandwidth 계산
bandwidth = 1.05height x 1.3width * reflesh_rate
예를 들어 1028x1024 @ 60Hz = 1.05*1024 * 1.3*1280 * 60 = 107MHz
VGA 640x480 @ 60Hz = 1.05*640 * 1.3*480 * 60 = 25.159680 Mhz
EGA 640x200 @ 60Hz = 1.05*640 + 1.3*480 * 60 = 10,483200 MHz
21 How do I calculate how much VRAM/DRAM I need?
640x480x24 bit colour = 921600 (min. 1 Meg card)
800x600x16 bit colour = 960000 (min. 1 Meg card)
800x600x24 bit colour = 1440000 (min. 2 Meg card)
1024x768x16 bit colour = 1572864 (min. 2 Meg card)
1024x768x24 bit colour = 2359296 (min. 4 Meg card)
1280x1024x8 bit colour = 1310720 (min. 2 Meg card)
1280x1024x24 bit colour = 3932160 (min. 4 Meg card)
1600x1200x24 bit colour = 5760000 (min. 6 Meg card)
32 How does a video accelerator work, and will one help me?
CPU가 픽셀을 다 처리하지 않고 cpu는 최소 입력만 주고 vga가 기능을 갖는다.
-the background fill pattern
-the location and contents of rectangular regions, i.e. windows
-and has adequate memory to store them.
To move a window, the CPU has to transmit something like:
-'move window' instruction
-window ID
-location to move to
This frees the bus and CPU to execute other tasks.
bitmap and pixmap transfers and painting, movement of sprites and icons, opening and closing of windows, filling with solid colours and patterns, line drawing, polygon painting, etc
As a result, even an ISA bus accelerator video card can provide blistering speed improvements over VGA in graphical environments like Windows 3.1, OS/2, X Windows (i.e. XFree86) and AutoCAD
Some newer accelerator cards include functions for 3D graphics rendering like polygon shading, coordinate manipulation and texture mapping. Others provide on-the-fly magnification of video clips so that those MPEG movies don't appear in a box that's three inches wide and two inches high on your screen.
61 Circuit for Converting from VGA to Fixed-Freq. RGB
[From: Roger Wolff (R.E.Wolff@et.tudelft.nl)]VGA video signal generation
-------------------------------------------------------------
http://lslwww.epfl.ch/pages/teaching/cours_lsl/ca_es/VGA.pdf
HSYNC, VSYNC 발생 타이밍은 다음과 같다.
HSYNC
___________________ _________
|____|
<------------->
640
<------------------>
660
<----------------------->
756
<--------------------------------> h_count
800
VSYNC
___________________ _________
|____|
<------------->
480
<------------------>
494
<----------------------->
495
<--------------------------------> v_count
525
VGA timing information
--------------------------------------------------------
http://www.epanorama.net/documents/pc/vga_timing.html
Horizonal Timing
Horizonal Dots 640 640 640
Vertical Scan Lines 350 400 480
Horiz. Sync Polarity POS NEG NEG
A (us) 31.77 31.77 31.77 Scanline time
B (us) 3.77 3.77 3.77 Sync pulse lenght
C (us) 1.89 1.89 1.89 Back porch
D (us) 25.17 25.17 25.17 Active video time
E (us) 0.94 0.94 0.94 Front porch
______________________ ________
________| VIDEO |________| VIDEO (next line)
|-C-|----------D-----------|-E-|
__ ______________________________ ___________
|_| |_|
|B|
|---------------A----------------|
Vertical Timing
Horizonal Dots 640 640 640
Vertical Scan Lines 350 400 480
Vert. Sync Polarity NEG POS NEG
Vertical Frequency 70Hz 70Hz 60Hz
O (ms) 14.27 14.27 16.68 Total frame time
P (ms) 0.06 0.06 0.06 Sync length
Q (ms) 1.88 1.08 1.02 Back porch
R (ms) 11.13 12.72 15.25 Active video time
S (ms) 1.2 0.41 0.35 Front porch
______________________ ________
________| VIDEO |________| VIDEO (next frame)
|-Q-|----------R-----------|-S-|
__ ______________________________ ___________
|_| |_|
|P|
|---------------O----------------|
여러 그래픽 카드에 대한 정보
------------------------------------------------------------
http://stason.org/TULARC/pc/video-faq/index.html
http://stason.org/TULARC/pc/video-faq/62-What-is-VGA-and-how-does-it-work.html
Graphics Controller: Can perform logical functions on data being written to display memory.
Display Memory: A bank of 256k DRAM divided into 4 64k colour planes. It is used to store screen display data.
Serializer: Takes display data from the display memory and converts it to a serial bitstream which is sent to the attribute controller.
Attribute Controller: Contains the colour LUT (Look Up Table) which determines what colour will be displayed for a given pixel value in display memory.
Sequencer: Controls timing of the board and enables/disables colour planes.
CRT Controller: Generates syncing and blanking signals to control the monitor display.
The VGA modes are:
Mode Type Resolution Chars Colours
(Hex)
0,1 text 360x400 40x25 16
2,3 text 720x400 80x25 16
4,5 gfx 320x200 40x25 4
6 gfx 640x200 80x25 2
7 text 720x400 80x25 mono
D gfx 320x200 40x25 16
E gfx 640x200 80x25 16
F gfx 640x350 80x25 mono
10 gfx 640x350 80x25 16
11 gfx 640x480 80x30 2
12 gfx 640x480 80x30 16
13 gfx 320x200 40x25 256
대부분의 PC모니터는 다음 MDA/Hercules/CGA/EGA 모드를 지원
Display Compatible Colours Text Graphics Scan
Adapters Res. Resolution Rates
----------------------------------------------------------------------
Monochrome MDA 640x350 Vert-50 Hz
Hercules 2 80x25 720x350 Hor-18.43 kHz
EGA 720x348
----------------------------------------------------------------------
Color CGA 16 40x25 320x200 V-60 Hz
EGA 80x25 640x200 H-18.43 kHz
----------------------------------------------------------------------
Enhanced CGA 16 of 40x25 320x200 V-60 Hz
Color EGA 64 80x25 640x200 H-18.43 kHz
640x350 or 21.8 kHz
----------------------------------------------------------------------
Multisync CGA 16 of 40x25 320x200 Variable
digital EGA 64 80x25 640x200
640x350
----------------------------------------------------------------------
Multisync VGA 256 of 80x25 640x480 Variable
analog 256k 800x600
----------------------------------------------------------------------
VGA Color VGA 256 of 40x25 320x400 V-70 Hz
display 256k 80x25 640x400 H-31.5 kHz
VGA Mono 320x350
display 640x350
720x350
720x400
640x480
----------------------------------------------------------------------
20 How do I calculate the minimum bandwidth required for a monitor?
Bandwidth 계산
bandwidth = 1.05height x 1.3width * reflesh_rate
예를 들어 1028x1024 @ 60Hz = 1.05*1024 * 1.3*1280 * 60 = 107MHz
VGA 640x480 @ 60Hz = 1.05*640 * 1.3*480 * 60 = 25.159680 Mhz
EGA 640x200 @ 60Hz = 1.05*640 + 1.3*480 * 60 = 10,483200 MHz
21 How do I calculate how much VRAM/DRAM I need?
640x480x24 bit colour = 921600 (min. 1 Meg card)
800x600x16 bit colour = 960000 (min. 1 Meg card)
800x600x24 bit colour = 1440000 (min. 2 Meg card)
1024x768x16 bit colour = 1572864 (min. 2 Meg card)
1024x768x24 bit colour = 2359296 (min. 4 Meg card)
1280x1024x8 bit colour = 1310720 (min. 2 Meg card)
1280x1024x24 bit colour = 3932160 (min. 4 Meg card)
1600x1200x24 bit colour = 5760000 (min. 6 Meg card)
32 How does a video accelerator work, and will one help me?
CPU가 픽셀을 다 처리하지 않고 cpu는 최소 입력만 주고 vga가 기능을 갖는다.
-the background fill pattern
-the location and contents of rectangular regions, i.e. windows
-and has adequate memory to store them.
To move a window, the CPU has to transmit something like:
-'move window' instruction
-window ID
-location to move to
This frees the bus and CPU to execute other tasks.
bitmap and pixmap transfers and painting, movement of sprites and icons, opening and closing of windows, filling with solid colours and patterns, line drawing, polygon painting, etc
As a result, even an ISA bus accelerator video card can provide blistering speed improvements over VGA in graphical environments like Windows 3.1, OS/2, X Windows (i.e. XFree86) and AutoCAD
Some newer accelerator cards include functions for 3D graphics rendering like polygon shading, coordinate manipulation and texture mapping. Others provide on-the-fly magnification of video clips so that those MPEG movies don't appear in a box that's three inches wide and two inches high on your screen.
61 Circuit for Converting from VGA to Fixed-Freq. RGB
[From: Roger Wolff (R.E.Wolff@et.tudelft.nl)]
VGA connector monitor
R ----------------------------------------------------- R
gnd ----------------------------------------------------- gnd
G ----------------------------------------------------- G
gnd ----------------------------------------------------- gnd
B ----------------------------------------------------- B
gnd ----------------------------------------------------- gnd
___________
| |
| 74HCT86 |
| |
| |
hsync -----------|1 |
| 3|----------------------------- Csync
vsync -----------|2 |
| |
| |
| |
gnd--+--|7 14|--+-- +5V
| |___________| |
| |
|________||_______|
||
0.1 uF
Use COAX cables for the "data" (R, G, B) lines. You can use just about anything for the hsync and the vscyn lines but keep them as short as possible. Around 30 cm (a foot) is fine. I use a COAX cable for the Csync line too, as I need a BNC connector at the end of the monitor anyway. I didn't do anything about termination, and all seems to be A-OK.
I gather the power for the 'HCT86 from inside the computer. You can find something yourself (find a 5V powerline going to the leds or something), or use something that resembles those "add-on" fans. The latter usually use 12V, but they show the principle: a male and a female cable connector and 6 wires should do the trick.
This worked for my Grayscale monitor (where the R and B lines are not needed), and now works just fine for my 21" monochrome monitor.
I start X at boot-time, before ANYTHING runs: my Xserver owns PID 3. I then quickly bring up the network and start an Xconsole. This allows me to follow the rest of the bootsequence.
VGA to RGB + composite sync -converter Designed by Tomi Engdahl
----------------------------------------------------------------
http://www.tkk.fi/Misc/Electronics/circuits/vga2rgbs.html
Use COAX cables for the "data" (R, G, B) lines. You can use just about anything for the hsync and the vscyn lines but keep them as short as possible. Around 30 cm (a foot) is fine. I use a COAX cable for the Csync line too, as I need a BNC connector at the end of the monitor anyway. I didn't do anything about termination, and all seems to be A-OK.
I gather the power for the 'HCT86 from inside the computer. You can find something yourself (find a 5V powerline going to the leds or something), or use something that resembles those "add-on" fans. The latter usually use 12V, but they show the principle: a male and a female cable connector and 6 wires should do the trick.
This worked for my Grayscale monitor (where the R and B lines are not needed), and now works just fine for my 21" monochrome monitor.
I start X at boot-time, before ANYTHING runs: my Xserver owns PID 3. I then quickly bring up the network and start an Xconsole. This allows me to follow the rest of the bootsequence.
VGA to RGB + composite sync -converter Designed by Tomi Engdahl
----------------------------------------------------------------
http://www.tkk.fi/Misc/Electronics/circuits/vga2rgbs.html
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| GAL PLD programming (0) | 2008.11.05 |
| 어드레스 버스, 데이터 버스 TTL (0) | 2008.11.05 |