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using VBXE with VGA monitors

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It seems it's not clear to the public on how to use VBXE with VGA monitors, so i've made something to cover this

hope this helps somebody.

As mentioned in the document, VGA for PAL systems is hit and miss, especially with LCD monitor since most of them don't know how to handle 31khz HSYNC with 50HZ VSYNC signals - CRT should don't care and display it flowlessly, but i guess it's not the point.

For NTSC regions this might be a perfect choice since there is no real RGB capable LCD monitors out there, and NTSC VBXE VGA generated signal is up to the specs for these and should pose no problems.

 

happy hacking.

Please read carefully whats in the documentation about RDY/CSYNC pin, and if you're unsure, or can't really solder - let someone else who can do it.

FPGA chips are not that fragile, but still, they don't grow on trees and replacing one if damaged  won't be plesant thing to do.

 

 

vbxe2-vga.pdf

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I'm tempted to give this a try though lacking the required crystal (and not willing to steal one from one of my 3 Amiga 500s - as it is I've got a 7800 that's running an NTSC crystal as I stole it's original one to use with my VBXE)

I was surprised with Sophia that I tried it on probably 6 or 7 monitors here in analog and DVI mode and it worked practically every time.

Though of course that was 16 Khz HSync, not 31.

 

I also have one of those GBS 8200 clone video converters I use with VBXE though I'm fairly sure it buffers the video and outputs 60 Hz.

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yes, gbs buffers whole frame, thus the lag, tearing and ability to work with any input source vertical frequency

whereas vbxe and vbxe alike devices just buffer enough to display same line multiple times to get the job done, these need only a single line delay but have their flaws aka decreased compatibility

this is all fine if you're driving TFT or LED panel directly, as signal range it can accept is quite wide, but not so much when it comes to consumer-grade monitor, that has preprogrammed few dozens of input signal resolutions and it searches through the table to find closest match

 

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