Sunday, 19 November 2017

Bitty Data Logger 3.1.0

Bitty Data Logger 3.1.0 provides more ways to export and share data captured with the app. Previously, data was exported by uploading it to the free of charge, 3rd party transfer.sh service. There have been reports that this service is becoming unreliable and that it may even be shut down and so this new release is a response and solution to that issue.

On Android devices you may now export by:
1. Using your device's Share facility, using the application of your choice. Google Drive and email are good choices.
2. Saving to the local Downloads folder on your device. You can find it using the Google Downloads app on your device and then open it using a suitable app or share it using Android Share.
3. Copy and Paste. Copy your data to the clipboard and then paste it into a suitable destination like a new email.
4. FTP - use the File Transfer Protocol to transfer your data file to an FTP server which you have access to.
5. HTTP - use multi-part HTTP upload to the web server of your choice. This is the direct replacement for the upload facility in previous releases. Specify a URL of "https://transfer.sh" to continue to use transfer.sh, but be aware of the issues with this service described above.

On iOS devices, (1) Share, (3) Copy and Paste and (5) HTTP are available.

You are advised to uninstall the current version and then install the new version for best results.

Happy logging!


Monday, 6 November 2017

Bitty Data Logger 3.0

Bitty Data Logger is an application which can capture and chart data from a BBC micro:bit's internal accelerometer, magnetometer and temperature sensors. It's available for iOS and Android smartphones and tablets and for Chromebook as well. Data is transmitted from the micro:bit to your smartphone over Bluetooth so you can be some distance away from the micro:bit and.... whatever you have connected to it.

Version 3.0 for iOS and Android was released today and adds an exciting and hopefully, very useful major new feature. It's now possible to capture, chart and export data from devices like sensors which you have connected to the micro:bits pins on its edge connector.

The micro:bit edge connector

You can connect up to three things at a time, to pins 0, 1 or 2. What might you connect? All sorts of things! I've mostly been experimenting with a TMP36 temperature sensor and a couple of Light Dependent Resistors (LDRs) but you could connect any electrically compatible sensor, be it for measuring humidity, acidity, the occupancy of a room or anything else you can measure in the environment.

A temperature sensor and two LDRs

As a way to investigate physical phenomena and the behaviour of electronic circuits, Bitty Data Logger is a fantastic tool. Visualising behaviours using real time charts is a highly effective way of helping to develop an understanding of the behaviour. And Bitty Data Logger's export facility lets you take the captured data and process it in another tool like a spreadsheet.

With the new sensor logging capability, you can opt to log the raw data values read using the micro:bit's APIs, convert these values to millivolts or, you can supply your own formulae with which to calculate derivable values. For example when I have my TMP36 temperature sensor connected to pin 0, I use the following formula to convert the raw micro:bit data into the corresponding temperature in degrees celsius:

  ((p0_raw * 3300 / 1024) - 500) / 10

Data acquired from the micro:bit pins can be processed by formulae in real time
I think there's tons of potential for Bitty Data Logger and micro:bit in the classroom and coding workshops and would love to hear what people think.

Meanwhile, I've been having fun testing and trying out various sensors. Here are some screenshots to close this short post.

Temperature sensor data in raw micro:bit format

Temperature data, converted to degrees Celsius using a pin formula

Light sensor (LDR) data in mV: sensor being repeatedly blocked then opened to the light
That's it! For more information, see http://www.bittysoftware.com/apps/bitty_data_logger.html.You'll also find coding tutorials which explain how to write the code you'll need on your micro:bit too. Enjoy!