A simple universal 800×600 VGA signal generation circuit

You may have seen this article where I discussed a 640×480 VGA signal generator that I designed and built. The signals, that circuit generated, were correct when measured with an oscilloscope. However, I concluded that I didn’t know why my display hardware had a hard time displaying an image and I found the reason for that and updated the circuit to generate the necessary signals for displaying an 800×600 image with a refresh rate of 60 Hertz.

Continue reading A simple universal 800×600 VGA signal generation circuit

VGA signal generation using discrete electronic components

Note: An updated version of this article is available here! However, this article remains valid and I placed a note in every section that got updated.

It’s been a while since I published this series of articles on nerdhut about monochrome video signals for an old Macintosh CRT. I wanted to post a short follow-up article about VGA and how to generate such signals. This article will also be a follow up to the custom CPU series and it will be another step towards the custom computer, I always wanted to design and build.

However, in this article, I only want to take a look at how the standard 640×480@60Hz VGA-Signal can be created using a screen testing device, made from discrete electronic components, which can be used to test monitors without the need of a computer being around. Continue reading VGA signal generation using discrete electronic components