OpenLog is a data logger from SparkFun electronics that is touted as being easy to use and a reliable writer to a microSd card. I haven’t found that to be true, I think it is a pain in the a** but maybe that’s the experience more than the actual product. I ordered the data logger in January and got busy and didn’t have the time to use it so I set it aside.
Really the only reason I ordered it was because I could not get GoBetwino, a Freeware Arduino Data logging software program to work. The GoBetwino program uses a USB connection to a computer connected to the Arduino to log to a file on the PC. A great concept that I tested and worked fine on the desktop machine. However on the laptop that I was using to make changes to the Arduino controlling the boiler in the shop it didn’t work. It seemed easier to come up with a standalone solution rather than troubleshoot the USB connections, the power managment issues with the Laptop etc. So I bought the data logger.
As I wrote in an earlier post since the time of my purchase of the OpenLog board it was recommended to update the firmware, this required updating the board with a FTDI board that accepts the USB connection from the PC to update the firmware, after 2-3 hours of frustration this task is finally completed. The main problem being Windows XP didn’t seem to recognize the FTDI board and assign it a com port but finally was able to find the correct driver and download the firmware.
I ran the test sketch, pulled the micro SD card and reviewed the data. The board did log the data correctly so the next step is to write a function that writes temperature data to a file with a time stamp. Since I have an Arduino on my desk with a real time clock chip that measures the outside temperature as well as the temperature of a solar hot water storage tank this would seem like a perfect application to test. After testing the function in that application it will be easy to modify the function for the monitoring of the boiler function. I prefer to write the code in functions and call the functions from the main body of the loop. This makes the code modular and easy to reuse. I comment very carefully and probably over comment, but I personally prefer to make the code painfully simple to understand on the assumption I may not look at the code again for a few years. I am hoping you will comment as well since your comments will no doubt improve the code.
I will post the function when I complete it. Thanks for reading.