I’ve been playing with some very cheap, but quite good power meters made by Eastron for a few years now, in particular their compact (single-DIN) single phase Modbus meters. They are great for cheap (non-commercial) energy monitoring applications. The SDM120M variant has Modbus over RS-485 support for convenient data acquisition and integration. These aren’t the […]
I recently had a problem with a particular Raspberry Pi and was able to rescue some files. I thought I’d document this here in case it’s useful. When powered on, I got an endless output of “mmc0: fsm 1, hsts 1” scrolling on the screen. Not good! My limited understanding of this error is that […]
I recently wrote a bash script that automates a database backups to zipped files on a Raspberry Pi. I would then periodically SSH in and transfer the backup files. This was a simple temporarily and manual solution, but I wanted a way to automate sending these files to a remote backup. I use AWS quite […]
Recently I had the need to upgrade MySQL on a Raspberry Pi running the latest standard distribution version of Jessie. I needed to use the JSON data-type as a MySQL field. My Raspberry Pi (as of April 2017) was running MySQL 5.5.52, but I needed 5.7+ for the JSON data-type. Update MySQL I’m providing these […]
When I first began using the Raspberry Pi to run Java applications, Oracle had yet to release a Java virtual machine that utilised ARM hard floats (hardware accelerated floating-point math processing). This meant that the Oracle JVM had to do all of this arithmetic in software causing excessive CPU load and poor performance. It was […]
Sometimes it’s necessary to leave a publicly accessible SSH connection available on your Raspberry Pi. While a strong password is essential, a much more secure method for authentication is to use a public and private key system. This guide will take you through all of the steps to creating the keys, configuring the Raspberry Pi, […]
I’ve finally managed to fire up the original Protek 608 software on an old Dell Inspiron 8100 I found stowed at the office. My previous attempts to run this software failed on Windows 8 and 10, and there’s very little information about how this software looks and operates (it’s quite niche). I decided that it […]
As detailed in a previous post, the physical communications layer is RS-232 – 9600 baud, 7, N, 1. So we know how to correctly connect the the multimeter and handle the data transfer, but how is the data interpreted? What’s the language or meaning? In this post I detail all of this, starting with the […]
Please note this is an alpha release. Version 0.3.0 is still under development use with caution! 😉 If you find jGauge useful a link back to the home page jgauge.com or my blog dariancabot.com is appreciated. See the main project page for more information and downloads. Getting Started Include these files in the head of […]
I’ve found debugging my JavaScript projects much easier since using the Firebug add-on for Firefox, but more specifically outputting to the Firebug console. It’s as easy as this: var myVar = 42; console.log(‘my variable: ‘ + myVar); This will output ‘my variable: 42‘ to the Firebug console, just like using System.out.println() in Java. There are […]