[Tinyos-help] ADC DC offset Voltage...

Michael Schippling schip at santafe.edu
Fri Sep 23 13:49:25 PDT 2005


Not sure if this is any help, but on mica2/z
ADC0 is already assigned to the RSSI. I haven't
looked at the telosB schematic... Also it
may be defaulted to output in which case it
could sink a fair amount of current.
MS


Joe Polastre wrote:
> What version of TinyOS are you using?  I don't know what release
> Crossbow distributes with their motes, but I would recommend upgrading
> to 1.1.13 (don't use 1.1.14, it has a bunch of bugs)
> 
> -Joe Polastre
> Moteiv Corporation
> 
> On 9/19/05, Mike Deneen <mpdeneen at gmail.com> wrote:
> 
>>Hello all,
>> 
>> I'm just getting started with the Crossbow Telos B motes and I'm trying to
>>read the voltage off of a microphone.  Since the signal will swing positive
>>and negative and I'd like to get as much of the 0-3V input swing as
>>possible, my amplifier's output has a 1.5V dc offset.  When I connect the
>>amp output to the ADC pin, the voltage drops to about 10 mV.  When I
>>disconnect the ADC pin the voltage goes back to 1.5V.  The pin is ADC0, if
>>that matters at all.
>> 
>> I've searched the archives and there seem to be plenty of people who are
>>doing what I want to do, so I must be doing something wrong.  
>> 
>> Little help?
>> 
>> Thanks,
>> 
>> -Mike
>> 
>>_______________________________________________
>>Tinyos-help mailing list
>>Tinyos-help at Millennium.Berkeley.EDU
>>https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
>>
>>
>>
> 
> 
> _______________________________________________
> Tinyos-help mailing list
> Tinyos-help at Millennium.Berkeley.EDU
> https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help


More information about the Tinyos-help mailing list