[Tinyos-help] [TinyOS-help]Amplitude Changes When Setting Different Sample Period‏

[Chenni Qian]

Hi,

I am using the TinyOS and Tmote Sky to collect data from a vibratab. I  
installed the nesC code to the Tmote Sky. But the data collected is  
very strange. When the vibratab is not vibrating, if I set the sample  
period as 256ms, the amplitude of the PC oscilloscope is below 100  
while if the sample period is 20ms, the data becomes around 1200.  
Besides, even if I remove the vibratab so that there is nothing input  
to the ADC12, the amplitude shown is still about 800. Is it the  
software or the hardware that cause the problem? The vibratab is in  
well performance and the code is the original code. How can I solve  
the problem?

Thank you very much!

Best wishes,

Chenni