23 Mar 2018

Extech CO250 Protocol Details

Extech CO250 Protocol Title

Note: This post is currently just some loose notes during my R&D, and is a continuation of the Extech CO250 project. See my Extech CO250 review here. I have RS-232 details and teardown here. Open-source Java library I have a working Java library that reads all values over serial and provides statistics (minimum, maximum, average, […]

22 Mar 2018

Extech CO250 RS-232 details

Extech CO250 Title

The Extech CO250 (AKA Senseair pSENSE RH) is a relatively cheap handheld air quality measurement device with decent features. It measures carbon dioxide (CO2), dry-bulb temperature, and relative humidity, and also provides calculated dew-point and wet-bulb temperatures. One interesting feature, and the subject of this post, is it’s serial communications port. It comes with a […]

18 Apr 2016

Sanden PET-07 Power Supply RS-232 Module Reverse Engineering – Part 2

Sanden Title 2

In this video we take another look at the RS-232 plug-in module for the Sanden PET-07 CC/CV power supply. In particular, we see how the voltage output can be controlled and how this clears up some ambiguity with the circuit design. In part three, we will *finally* attempt to communicate using RS-232 to monitor and […]

10 Apr 2016

Sanden PET-07 Power Supply RS-232 Module Reverse Engineering – Part 1

Sanden Title 1

In this video we take a look at the Sanden PET-07 CC/CV power supply. In particular we look at the RS-232 plug-in module and attempt to make sense of the signals between the main board and plug-in board. In part two, we’ll apply this knowledge to attempt to receive RS-232 data from the power supply. […]

22 Oct 2015

Protek 608 original Windows software

Protek 608 Windows software v1.02

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 […]

30 May 2015

Protek 608 RS-232 details

Protek 608 RS-232 login analyser

This is following on from my previous post introducing the Protek 608 multimeter and my software project. In this post I detail the communications hardware, an important consideration for future development. The Protek 608 uses an RS-232 connection to allow for interfacing with a PC. This is a very common connection that most DMMs used. […]

26 Mar 2012

Home-made GPS and compass update

GPS and compass project - Breadboard prototype

After posting my project I had a number of questions online. I thought this is a good opportunity to update the blog to share more information on this project. GUI concepts I’ve made some more progress on the software side of things, mostly just playing around with the graphics display. The Nokia 3310 LCD screen […]