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Unread 14-02-2008, 12:01
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Re: How do I change the Gyro & Acc analog chanels?

Quote:
Originally Posted by TEAM1949 View Post
Did that (anabled another 2 analog chanenls) and consequently the Gyro won't give me any accurate values. I guess it's because of the change in the sample rates.
What else can I do ? Change some other definitions?
This expression, from adc_readme.txt, will allow you to calculate the update rate:

Update Rate = Sample Rate / (Samples Per Update * Number Of Channels)

If you are sampling three ADC channels and left the other settings at the default, you're only getting ~17 updates per second, which is pretty low. You'll want to bump this up to somewhere in the 50-100 updates per second range by raising the sample rate and/or lowering the number of samples per update. For grins, try changing the sample rate to 1600Hz and change the samples per update to 8 and see if it's any better.

-Kevin
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Kevin Watson
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