02-16-2020, 09:04 PM
(02-15-2020, 11:37 PM)Sebastian Staacks Wrote: So, I have good news and bad news for you:
The good news is that I created a configuration to read the magnetometer from my micro:bit and added it to the Wiki page as an example. You can find the config there: https://phyphox.org/wiki/index.php/BBC:M.../_Calliope
The bad news is that - at least for my micro:bit - the readings are not usable for anything. The problem is that each axis is reported as a 16bit value that can range from -32,000 to +32,000 (approximately) and unfortunately, they overflow several times while rotating the device. So, for example the x axis value would rise to 32,000, jump to -32,000 while still rising and then falling after actually reaching a maximum. I am not sure if this is a specific problem with my device (I also triggered the calibration to try and fix this) and I could not find whether there is a factor with which actual units should be derived, but it is definitely not a phyphox issue as the behavior can be seen in the raw data in nRF Connect as well. So, hopefully it is only my device that does this...
Dear Sebastian,
i tested the config file and got the same results. Also Adafruit says, that the measurement isn't very convincing. Probably i try to measure the total strength. The values were partialy convincing, showing up to the orientation the same value for all three directions. Also for slow movements, it worked out sometimes.
I didi succeed with the Acceleration. The values were good, but according to Lancaster the value should be divided by 1000 and this didn't work. Is it due to the int16LittleEndian?
I attached the QR-Code from the Editor. Will try the others option during the upcoming week. Thanks for all your help.
Best wishes Johannes