EGA and VGA plug pinouts
Matthew A. Clapp
and can't seem to find them.
Also, could someone tell me if the following is feasible: What I want to do
is to take a VGA card output to an EGA monitor. I know VGA mode won't work!
But will the EGA mode of the VGA card be OK? I was thinking of making a
VGA to EGA plug adapter, and just being very careful not to put my VGA card in
VGA mode.
Thanks,
Matt
Sam Goldwasser
Original VGA (31.5 KHz - 640x480)/SVGA (35-37 KHz - 800x600) 15 pin sub D:
6
1 Red (Analog) 6 Red Return 11 (ID0) GND (Color) 11. . . 1
2 Green (Analog) 7 Green Return 12 (ID1) NC (Color) . . .
3 Blue (Analog) 8 Blue Retuen 13 Horzontal Sync . . .
4 Reserved 9 No Connect 14 Vertical Sync . . .
5 Ground 10 Ground 15 No Connect . . .
15 10 5
Note: Monitor ID Lines ID1,ID0=NC,G for color; G,NC for Mono. ID0 only may
be used.
Mono VGA is similar using only the Green Video and Return.
******************************************************************************
VGA (VESA Standard) my...@fc.hp.com (Bob Myers)
Note that many of the pins shown above as "no connects" (actually, these
were sometimes used as monitor ID bits by many manufacturers) are now
defined under the VESA Display Data Channel standard. This standard provides
two protocols for display ID and control, including support for the full
ACCESS.bus interface. The current definition of the "VGA" pinout per the
DDC standard is:
6
1 Red (Analog) 6 Red Return 11 Monitor ID0 (opt.) 11. . . 1
2 Green (Analog) 7 Green Return 12 Data (SDA) . . .
3 Blue (Analog) 8 Blue Return 13 Horzontal Sync . . .
4 Reserved 9 +5 VDC (frm host)* 14 Vertical Sync . . .
5 Return 10 Sync return 15 Data clock (SCL)* . . .
15 10 5
Those signals marked with an asterisk would be supplied by the host only
if the host supports the DDC2 protocol (I2C or ACCESS.bus).
******************************************************************************
EGA - TTL (15.74-21.85 KHz) 9 pin:
1 GND 6 Secondary Green Video/Intensity
2 Secondary RED Video 7 Secondary Blue Video
3 Primary RED Video 8 H Sync TTL Positive
4 Primary GREEN Video 9 V Sync TTL Negative
5 Primary BLUE Video
CGA - TTL (15.75 KHz - 320x200 or 640x200) 9 pin:
1 GND 6 Intensity
2 Unused 7 Unused
3 RED Video 8 H Sync TTL Positive
4 GREEN Video 9 V Sync TTL Positive
5 BLUE Video
Monochrome - TTL (18.43 KHz - 720x350) 9 pin:
1 GND 6 Intensity
2 Unused 7 Video
3 Unused 8 H Sync TTL Positive
4 Unused 9 V Sync TTL Negative
5 Unused
Lance Corey
>Thanks,
>Matt
Unless the VGA card has a 9 pin connector, I would say it would be
difficult to built a unit to change the VGA signal to an EGA signal
since you would need a frequency clock (for determining which pixel is
current), and change the analogue signal to a digital signal. Anyhow,
the pins are :
EGA VGA
1 ground Red
2 S. red Green
3 Red Blue
4 Green reserved
5 Blue digital ground
6 Intensity/s. green Red return (analogue ground)
7 Mono video/s. blue Green return
8 Horizontal drive Blue return
9 Vertical drive Plug
10 Digital ground
11 Monitor sensor 0
12 Monitor sensor 1
13 Horizontal drive
14 Vertical drive
15 reserved
Lance Corey
Dept. Pharmacology & Therapeutics
University of British Columbia
Howard Del Fava
Won't work.
EGA is digital signals
VGA is analog
George Jefferson
:EGA is digital signals
:VGA is analog
how can you tell the various monitor types appart? I have a laptop
with a port marked "rgb"..well, it looks like a vga port.
--
george
geo...@mech.seas.upenn.edu
Sam Goldwasser
> :EGA is digital signals
> :VGA is analog
> how can you tell the various monitor types appart? I have a laptop
> with a port marked "rgb"..well, it looks like a vga port.
What laptop? Early laptops were CGA. Newer are VGA/SVGA. If it
has a 9 pin connector, it could be either EGA or CGA but more likely CGA.
If the connector is 15 pins, it is VGA.
If you have a scope, look at the Hsync timing: CGA: 15.7 KHz, EGA probably
around 22 KHz, VGA 31.4 KHz.
--- sam