# Hardware: Monitor ID pins

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Zelord    130
I'm doing a project in, where i want to interface with a standard monitor through a VGA connector and read back some information (Resolutions and stuff)from it. Not through a graphics card, but through a PIC16. Of course it is not working :/ I connect in the following way:

Port----------------ID pin
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15k ohm
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+5V
The ID pin can either be connected to GND or N/C (Not Connected) So if the pin is GND i should read a 0 on the port and a 1 if N/C. Accoding to [url]http://www.epanorama.net/documents/pc/vga_bd15.html[/url] i should get atleast a 0 on VGA-pin 11 (ID0), which would signal that it is a color monitor...(and yes it is ;) ) But i just get 1, ei. it is not connected. I then tried the following:

+5V----260 ohm-----LED-----Monitor ID

The LED should light up if i find a GND (and works when i touch the power surply). But again not working with the ID bits. It should be noted that i don't connect any other pins while trying this, but the monitor is powered on (comes up with no signal). So my question is, is the ID pins obsolete? Anyone got a better refrence than the one i found? (been going through variations of, monitor ID, monitor ID obsolete, - not working, vga specification etc) Anyone got a link for how to display an image (next step, which i haven't either been able to find information, except max voltage level for analog pins)

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Zelord    130
Solved the problem, had to connect one of the monitor pins to ground to get a common ground >_<

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Monder    993
Quote:
 Anyone got a link for how to display an image

Displaying an image with a PIC won't be particularly easy, you may be able to get a 320X240 image out of it, however the entire thing will be dedicated to generating the VGA signals and not able to do any useful computation as well.

You may find these links interesting:

Pic-Tock
Pic-Pong

Which generate a video signal from a PIC, which admitidly is not a VGA signal, but at least its a video output.

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Guest Anonymous Poster
there are FPGA based chips for about $1-2 US that will allow you to directly address a buffer to map memory to monitor screen resolutions of up to 800x600@16bpp these chips can be easily connected to your PIC using a handful of pins. #### Share this post ##### Link to post ##### Share on other sites Zelord 130 Quote: Original post by Monder Quote:  Anyone got a link for how to display an image Displaying an image with a PIC won't be particularly easy, you may be able to get a 320X240 image out of it, however the entire thing will be dedicated to generating the VGA signals and not able to do any useful computation as well. You may find these links interesting: Pic-Tock Pic-Pong Which generate a video signal from a PIC, which admitidly is not a VGA signal, but at least its a video output. Well i'm only gonna display an image, so i only need to refresh the screen to precent it from fading away. Guess i could run it at 30 FPS, anyone know how low it is possible to go? And will a monitor accept a slower rate, ei is it a maximum rating that a monitor states, or the only way to run? And still, if anyone has information on how the sync signals should be coordinated with colors and such, then please post =) (Above links were for a TV, with a composite signal, instead of seperate lines. Need to find the timing values, which i'm pretty sure isn't the same) Quote:  Original post by Anonymous Posterthere are FPGA based chips for about$1-2 US that will allow you to directly address a buffer to map memory to monitor screen resolutions of up to 800x600@16bppthese chips can be easily connected to your PIC using a handful of pins.

No fun in that :P