-- Based on an AVR and a Raspberry Pi 0W running MPD
Figure 1. DIY Web Radio
Last year, a friend gave me a dead DAB+ radio, whose only function that still worked was the heater-function -- Oh, it wasn't supposed to do that? OK... Then it was 100% dead. --
Either way, I've been meaning to get myself an Internet radio for a while now, but all on the market were missing some feature I wanted, plus building one myself didn't sound too hard.
This post describes the radio that I built in the end, based around only the original case and speaker from the DAB+ radio.
-- Now that's my definition of building a computer!
Figure 1. The finished LW-35
Do you still remember the old electronic typewriters from the nineties? Many of the later machines were already pretty much full-fledged computers, just with a word processor as the operating system. One of these typewriters is the Brother LW-35 released in Europe. I still had one of these lying around; Great keyboard, a fun daisy wheel printer, and a 14 line display for distraction free writing. It even had a floppy drive for data exchange. So in summary, a pretty cool device.
But there were a few problems with it. First of all, the floppy drive stopped working reliably. And secondly, on the days the floppy drive decided to work, it was still a floppy drive. Not exactly the most convenient way to store and transfer data these days, although I'm sure some of you will disagree. Also, the typewriter used its own file format, which needed to be converted on the device itself before it could be read in a DOS or UNIX environment. This may be OK if you're writing a longer document, and only write it on that machine. But as someone who constantly changes the machine they type on, it's not practical.
Yet, even with these problems, I just didn't have the heart to throw it out.
So what can we do about it? Upgrade it!
In this post, I will show you how I converted my old LW-35 typewriter into a modern computer while keeping all the good features of the old machine.
-- Building an FPGA from 74-series logic ICs. For fun and education.
Figure 1. TTL-FPGA
Technology is becoming more complex every day. Devices get smaller, integration gets higher. Consequently, it is becoming increasingly harder to understand how modern devices work.
In the 80s, you could open your PC and start probing signals on the mainboard to understand which instruction the CPU executed. These days, pretty much everything can be integrated into a single chip and everything is hidden away. One example of such a highly integrated component is the field programmable gate array (FPGA).
FPGAs essentially allow the designer to create large digital designs inside of an IC without having to create actual new silicon. As these designs are created by writing software-like source code, one might easily forget the fact that what is created is, indeed, a digital circuit. The immense overhead to provide this flexibility is easy to underestimate when working with these devices.
To aid students learning about FPGAs better understand the technology, this project aims to provide a platform to look at the inner workings of such a chip by breaking it out of the IC and bringing it onto a PCB where every signal can be traced and measured. Such projects are often done for central processing units (CPUs), but there isn't much when it comes to FPGAs.
Before I delve any deeper into my implementation, I want to highlight that this is only one of many ways to construct such an "FPGA." Also, this project does not accurately represent the circuits inside a commercial FPGA. Many things, especially the routing, had to be grossly simplified in order to be feasible. The basic concepts, however, should still hold true.
Figure 1. Thank you for 2018! 2018 is coming to an end, and so it's time to tend to things that didn't get done over the year.
For me, I've been wanting to talk about many of my old projects for quite a while now, but never got around to it.
So this December (or tbh, many were shot during November), I pulled together and made videos for 25 of my projects. They date from very recent (November 2018) back to my school days (2007), so there's quite some variation to the style and type of project. I hope that you will enjoy (at least some of) them.
