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		<title>Back_End on Charlie Howlett</title>
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				<title>Reverse Engineering Roland TM-2</title>
				<link>https://charliehowlett.co.uk/posts/2026-06-19-trigger-module-reader/</link>
				<pubDate>Fri, 19 Jun 2026 00:00:00 +0000</pubDate>
				<guid>https://charliehowlett.co.uk/posts/2026-06-19-trigger-module-reader/</guid>
				<description>&lt;p&gt;While building my &lt;a href=&#34;https://charliehowlett.co.uk/posts/2025-05-03-building-compact-hybrid-drumming/&#34;&gt;compact hybrid drumming rig&lt;/a&gt;, I became very familiar with the Roland TM-2. The module has an enormous number of settings and even lets users save configurations to an SD card as &lt;code&gt;.TM0&lt;/code&gt; files. One day, I opened one of these files on my computer to see what was inside. I found mostly unreadable raw binary data, with a short string of plain English text at the top: the name of my save file. This led me to wonder whether I could reverse engineer the format and display all the information in a web-based user interface.&lt;/p&gt;</description>
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				<title>Arduino LoRa Monitoring System</title>
				<link>https://charliehowlett.co.uk/posts/2022-01-11-arduino-monitoring/</link>
				<pubDate>Tue, 11 Jan 2022 00:00:00 +0000</pubDate>
				<guid>https://charliehowlett.co.uk/posts/2022-01-11-arduino-monitoring/</guid>
				<description>&lt;p&gt;I rent a small drumming practice space that I share with several other musicians on a timetable basis. I built this monitoring system to understand how often people were using their booked time slots and how the room&amp;rsquo;s environmental conditions changed over time. Since the space has no Wi-Fi and unreliable mains power, the project became an interesting challenge involving low-power hardware, long-range radio communication, and remote data collection.&lt;/p&gt;&#xA;&#xA;&#xA;&#xA;&#xA;&#xA;&#xA;&#xA;&#xA;&#xA;&#xA;&lt;picture&gt;&#xA;  &lt;source&#xA;    type=&#34;image/webp&#34;&#xA;    srcset=&#34;https://charliehowlett.co.uk/posts/2022-01-11-arduino-monitoring/ArduinoMonitoring_hu_febdf34626a4b6ed.webp 520w, https://charliehowlett.co.uk/posts/2022-01-11-arduino-monitoring/ArduinoMonitoring_hu_2626646897062a3e.webp 1040w&#34;&#xA;    sizes=&#34;(max-width: 700px) 90vw, 520px&#34;&gt;&#xA;  &lt;img&#xA;    class=&#34;image-medium&#34;&#xA;    src=&#34;https://charliehowlett.co.uk/fallback-images/posts/2022-01-11-arduino-monitoring/ArduinoMonitoring.jpg&#34;&#xA;    alt=&#34;The Arduino monitoring hardware with sensors and radio module&#34;&#xA;    width=&#34;1500&#34;&#xA;    height=&#34;1500&#34;&#xA;    decoding=&#34;async&#34;&gt;&#xA;&lt;/picture&gt;&#xA;&#xA;&#xA;&lt;h2 id=&#34;sensor-node&#34;&gt;Sensor node&lt;/h2&gt;&#xA;&lt;p&gt;The sensing node is built around a 3.3V Arduino Pro Mini with sensors for PIR motion, humidity, temperature, and ambient light. Every ten minutes, it wakes up, collects readings, packs them into a small JSON payload, transmits the result by radio, and returns to sleep. I spent a significant amount of time reducing its power consumption so the device could run for roughly six months from three AA batteries. For this project, reliable long-term monitoring mattered more than collecting readings more frequently.&lt;/p&gt;</description>
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				<title>Automating Lights with a Raspberry Pi</title>
				<link>https://charliehowlett.co.uk/posts/2021-09-02-pi-lights/</link>
				<pubDate>Thu, 02 Sep 2021 00:00:00 +0000</pubDate>
				<guid>https://charliehowlett.co.uk/posts/2021-09-02-pi-lights/</guid>
				<description>&lt;p&gt;Pi Lights was a fairly simple idea and my first exploration into DIY home automation: measure the ambient light level throughout the day using a Raspberry Pi, then switch Wi-Fi lights on or off automatically.&lt;/p&gt;&#xA;&#xA;&#xA;&#xA;&lt;div class=&#34;video-frame teletext-box&#34;&gt;&#xA;  &lt;iframe&#xA;    class=&#34;video-frame__iframe&#34;&#xA;    src=&#34;https://www.youtube-nocookie.com/embed/ZpO6WK41Bb8&#34;&#xA;    title=&#34;Pi lights demo video&#34;&#xA;    loading=&#34;lazy&#34;&#xA;    allow=&#34;accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share&#34;&#xA;    referrerpolicy=&#34;strict-origin-when-cross-origin&#34;&#xA;    allowfullscreen&gt;&#xA;  &lt;/iframe&gt;&#xA;&lt;/div&gt;&#xA;&#xA;&lt;h2 id=&#34;implementation&#34;&gt;Implementation&lt;/h2&gt;&#xA;&lt;p&gt;The system polls several light-dependent resistors and averages their readings before deciding whether to switch the lights. Using multiple sensors and rate-limiting changes made the automation less sensitive to brief shadows or sudden changes in brightness. A dedicated light-sensing Raspberry Pi HAT would have been more accurate, but I wanted to see if I could build a first pass using components I already had lying around. I ran the software as a Linux service so it would start automatically and continue working in the background without needing any attention.&lt;/p&gt;</description>
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