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

Serial to parallel and parallel to serial conversion with shift registers

Shift registers can be used in a wide variety of applications. You can, for example, use them to convert multiple parallel data lines to a single serial line and vice-versa. This technique can be used to extend the number of available in- and outputs of a microcontroller and this article will show you how you can achieve this.

Continue reading Serial to parallel and parallel to serial conversion with shift registers

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

Autodesk 123D Circuits free breadboard simulator

Unfortunately, this online tool is no longer available. If you try to access it, you’ll be redirected to Autodesk’s new online CAD program called TinkerCAD, which is a great free CAD software btw.

If anybody is looking for a good (and free) breadboard simulator, i can recommend the one from Autodesk: 123D Circuits Continue reading Autodesk 123D Circuits free breadboard simulator