hi dominik, it's not the sd, it's the start-up behavior of the gyro.
this is a guess, albeit an educated one, but does the gyro act up mainly after you re-program the shimmer? does it clear up after a number of hard power cycles?
what's happening: during programming, in order to enter the bsl sequence, and sequence of resets is sent to the msp430. these can leave the gyroscope in a confused state, and the only way to clear it is a complete power-down and a clean (uninterrupted by resets) power-on. that's why the gyro driver does this, with a (iirc) six-second pause. occasionally the six seconds isn't enough, but it does suffice in light of the fact that (most) people don't re-program the shimmer every time they use it!
i hope that this helps, steve On 01/26/2012 04:43 AM, Dominik Schuldhaus wrote:
Hi, I have the following problem. The shimmer-firmware I use is able to write accel & gyro on SD card. The accelerometer values seem to be fine for every trial/record. But the behaviour of the gyroscope is strange. Sometimes one/two axes fail, sometimes all. There are also other strange artefacts. Does anyone have experience with gyroscope on SD? Best regards, Dominik
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