Martin from Sweden emailed me a few weeks ago about an open source software package for graphing roasting profiles. With the trip to Costa Rica, my work on software was delayed. This morning I loaded up the software and tried it. I was really impressed.
I have written software for graphing roasts from my HH506RA data logger connected to a computer and my HotTop roaster. My work focused on my hardware setup. When I built the coffee office I installed a small PC with the monitor acting as both TV and computer monitor. One of my plans was to use the monitor to track roasts.
Today I did a roast with the new software. The graph is not labeled yet. Each horizontal line is 100oF while each vertical line is 30 seconds. The system will handle Celsius but it uses the same scale right now. The data logger tells me which temperature system the readings are.
I now have the Omega HH506RA talking to the computer via the USB cable running the Omega software. The software works and you can log the results but it is clumsy to do what I want which is record the temperature and plot both probes every 30 seconds.
I found a small free Basic interpreter/compiler called Just BASIC www.justbasic.com. While I could write the application in a commercial language, I hope that by using a free language others can join in and play with the code.
My requirements are:
Select com port
Press a button to:
Load beans – Start logging
First Crack – Record time/temp
Second Crack – Record time/temp
Dump beans – Stop logging
Save log for uploading to the web
Plot log on a graph while it is logging
Compare to previous logs of the same profile
So far I can communicate to the logger, read values and translate the return values.
Some of the valuable resources for people working on this include:
Omega HH506RA Serial Protocol – http://www.jacquesf.com/blog/2010/03/omega-hh506ra-serial-protocol/ – The best description of the protocol and how to talk to the logger
My week at roasting school was amazing. Classes ran from 8:30 to 5:30 every day. We roasted on several small roasters but spent most of the week on a 5 kilo Probat and a slightly smaller Diedrich. The class was an interesting collection of people with most starting their own boutique roasters.
Classes covered the complete cycle from grading and storing green beans, roasting on various roasters, cupping to green bean purchasing.
One thing that struck me all week was the importance of the bean temperature. To this I bought an Omega HH506RA datalogger and two K-Type probes and added it to my HotTop. In this photo just the bean probe is installed. I will add the drum probe next.
I will post the details of the installation and results later