I have read through the datasheet of the ADXL343 several times and Googled this question, but I'm still confused. I'm trying to figure out how to understand the resolution of an accelerometer when used as a tiltmeter, in particular to the nearest fraction of a degree. I'm looking at the ADXL343.
I understand accelerometers only work as tilt meters when they are sitting still, otherwise I need a gyroscope. I also understand that they don't tell you tilt, but rather force, when sitting still from gravity, and that you get decimals of g as you rotate it. The ADXL343 has different ranges, from 1g to 16 g, and I think that means that if I set it to the 16g range rotate it 90 degrees I'll get a reading of 8g, is that correct?
Then there is the number of bits, which I think means the resolution across the selected range. So if I use the 2g range and 4096 bits I can get a reading to the nearest ~0.000489g, is that right?
Then, once I know that, how can I figure out how to relate g to degrees (or radians) so I can know the nearest part of a degree I can read?