My favourite Raspberry Pi 4 cases

Every Raspberry Pi deserves protection. Having used these boards since the first iteration, I have tried many cases over the years, all of them with their strengths and weaknesses. Now I’ve settled on a couple of firm favourites – both from Argon40. And to get this out of the way up-front, this post is not sponsored in any way. I’m… Read more »

ESP32 room thermometer: with 18650 battery level indicator

It seemed like a good idea at the time. The TTGO ESP32 microcontroller board that I’m using for a room thermometer project comes with a battery connect and charging circuitry for a Li-Ion cell. It would be so much easier to deploy the thermometer if I could run it off a battery. And it works. Kinda. There are issues, though…. Read more »

Network monitoring #2: Logging CPU temps with InfluxDB and Grafana

My previous method of logging the CPU temperatures of machines on the network involved a Bash script sending out a message via MQTT. This was intercepted and logged by a Python script running on a server, which wrote the data to text files in a place where the intranet server could see them. Phew! It’s a miracle it worked. But… Read more »

Battery-powered ESP32 IoT room thermometer with OLED display

A while back, I made a couple of ESP8266-based room thermometers. These have been beavering away happily ever since – one on the desk in my office and one in the living room (or salon as we say in France). The only significant change I’ve made to them is to add the capability for them to report temperatures to an… Read more »

Network monitoring #1: Server temperatures, MQTT and Bash

It’s always a good idea to know the state of the machines on your network. Plus, I’m a geek, and messing around with data appeals to me. One metric I especially like to keep an eye on is CPU temperature. Why? Why not? I’ve recently got into InfluxDB and Grafana, and that’s the way all future projects will be going…. Read more »

Are my lightbulbs phoning home?

      5 Comments on Are my lightbulbs phoning home?

Just lately I’ve been getting into home automation. No, not with ESP8266s and lots of soldering and programming – that comes next. I mean the easy way, by buying smart lightbulbs and switches. We have an old, dark house, which means we use a lot of lamps. Every morning, in the living room alone, we’d go around switching on seven… Read more »

The Dawnclock – back from the dead

I’d been waiting for this moment. I’m not a electronics or coding expert and so, sooner or later, I expect all of my projects to die. But the Dawnclock just kept on living – right up to the point when it didn’t. I first blogged about this project in January 2013, which means that it’s been operating for eight years…. Read more »

Zolatron 64 6502 homebrew computer – first boot

Okay, so the headline is overstating matters a little, but this thing is making progress. Here’s a quick series recap: I decided to brew my own 6502-based computer. Rather than start from nothing, I built a kit, with partial success. And I’ve been following along with Ben Eater’s 6502 project on YouTube. Both taught me a lot. However, even before… Read more »

Zolatron 64 6502 homebrew computer & Ben Eater’s project – changes to the ROM

In my previous post, I mentioned how, while I’m following along with Ben Eater’s 6502-based homebrew computer project, I’m also making some revisions of my own. One of these is to use my own address decoding scheme. So far, things are working okay, but that post included a note about how I’m going to have to make some changes to… Read more »

Following Ben Eater’s 6502 project – parts 5 & 6

Back in the first half of February, Ben Eater added parts 5 and 6 of his YouTube series on building a 6502-based homebrew computer. The enhancements he made gave the computer something it has been sorely lacking – memory. And the reason the computer needed memory was so it could have a stack. Up to that point, the code had… Read more »

Chatting at home with ejabberd on the Raspberry Pi

One of the problems with having just two people living in an old, rambling house is that you spend a lot of time shouting. My More Significant Other (MSO) and I work in different parts of the house – I have an office and she prefers to work on her laptop in the living room. We often need to communicate… Read more »

Zolatron 64 6502 homebrew computer – new address mapping and decoding

Although it is possibly the slowest computer development programme in history, my Zolatron 64 6502-based homebrew design has made some progress. And this is largely due to the fine folks over at the 6502.org forum. Specifically, I have made changes to how I’m mapping the 64KB address space and the decoding I’m using to do that. I’ve been following along… Read more »

Back on Twitter

      No Comments on Back on Twitter

Something weird happened to my Twitter account. I have no idea what or when, but at some point – maybe as long as a year ago – it stopped working. You’d think I’d have noticed, but the honest truth is that I treated Twitter as write-only media. I used it to announce new blog posts (which WordPress handles automatically) and… Read more »

Following Ben Eater’s 6502 project – part 4

Ben Eater’s exciting 6502 project has reached the next stage – adding a display. But before I could play along, I had some remedial work to do. I’d achieved the previous stage of being able to get the LEDs to light up, but not reliably. Something was glitching and would cause the machine to go haywire. This isn’t entirely surprising… Read more »

Making ROMs for the BBC Micro

      5 Comments on Making ROMs for the BBC Micro

Here’s something I’ve only just learned about the BBC Micro: you can burn ROM chips using modern EEPROMs. Who knew?* One of the strengths of the BBC Micro was the way it handled ‘language’ ROMs. The quotes are there because while many of these ROMs were, indeed, programming languages, others were applications such as word processors, spreadsheets, utilities and so… Read more »