In this article I’m going to show you how to do a straightforward modification to the STM32 F4 Discovery board that will change the onboard oscillator from 8MHz to 25MHz. Why do this Probably the main reason to do this is ethernet. If you’re prototyping an MII ethernet PHY then...
Modding the STM32 F4 Discovery with a 25MHz clock
posted by Andy
Arduino Uno R3 graphics accelerator shield uses no pins
posted by Andy
Hello and welcome to another in my series of unique hardware projects designed to bring you something useful that you’ve hopefully never seen before and at a price point that any hobbyist can afford. This project brings together the knowledge that I’ve gained over the last few years to bring you a graphics accelerator for the Arduino Uno R3 based on an ARM Cortex M0 core attached to a 640×360 LCD from the Sony U5 Vivaz cellphone. In previous articles you’ve seen how I’ve reverse engineered the Sony LCD and then used it in reflow oven and FPGA graphics accelerator projects. Introduction TFT LCD shields for the...
PCB soldermask colours: which one should you choose?
posted by Andy
I’m sure that all electronics hobbyists have, by now, noticed that anyone can get their PCBs printed at the online Chinese services such as Seeed Studio, ITead Studio and Elecrow. Many of you will have even used those services. I have, and I’ve used them often. Introduction When...
Exploring the KSZ8091RNA RMII ethernet PHY
posted by Andy
In my previous two articles (here, here) I’ve provided schematics and Gerbers for a breakout board that supports the Micrel KSZ8051MLL ethernet PHY. The KSZ8051MLL is an MII PHY manufactured in a reasonably easy to work with 48 pin quad-flat package. One of the burdens of MII is that it...
Hacking the HP Z800 Xeon motherboard into a standard case
posted by Andy
About four years ago now the company I work for were investing in some new servers for a project that we were working on and what turned up were quad LGA1366 socket Xeons with support for up to 192Gb of memory. In most cases two sockets were populated with Intel Xeon X5670 CPUs, hex core...
An FPGA sprite graphics accelerator with a 180MHz STM32F429 controller and 640 x 360 LCD
posted by Andy
A very warm welcome to my most ambitious project to date. In this project I’m going to attempt to design and build a sprite-based graphics accelerator that will function as a co-processor to an MCU. Using cheap off-the-shelf components I’m hoping to achieve a level of gaming performance that compares well to popular commercial hand-held gaming consoles. I’m hoping that I’ll learn a few new tricks along the way, and, if the ideas currently zinging around inside my head all land the right way up and in the right order then I should be able to write a demo or two, maybe even a small game as a proof of concept. Naturally...
An open-source Cortex-M0 halogen reflow oven controller with TFT LCD
posted by Andy
Introduction It’s been so long since I had the idea for this project that I can’t remember why I had the idea in the first place. At least I blame it on the passage of time although this engineer is getting on a bit now so it could easily be memory rot on my part. So here we are then, a reflow oven controller. Let’s quickly recap what a reflow oven is for those that are new around here. The two main processes used in industry to build printed circuit boards are wave soldering and reflow using a very large industrial oven that you probably can’t afford and if you could afford to buy it you probably couldn’t...
The KSZ8051MLL Ethernet PHY revisited
posted by Andy
It’s been more than a year now since I brought you my design for an ethernet PHY based on the Micrel KSZ8051MLL. The design was an unqualified success and I’ve been using it successfully with both the STM32F107 and the STM32F4 series MCUs coupled to the TCP/IP stack that I wrote...
