I'm using a TelosB mote attached to a custom-made breakout box to read  
data from four sensors.  The sensors are Decagon's 5TE model  
(http://www.decagon.com/literature/manuals/5TE.pdf) and the breakout  
box uses a 4-1 multiplexor/demultiplexor from Texas Instruments  
(http://www.datasheetcatalog.org/datasheet2/9/0o6p5fzdqee9l4dwqaq5o5ro6r3y.pdf).
  The ADC0, ADC1, and ADC2 pins are used to select which sensor to read from, 
and the readings are sent back to the UART receiving pin (the one next to the 
Vcc pin).  The main body of the code is provided at 
http://docs.tinyos.net/index.php/TinyOS_2.x_index_of_contributed_code#ECH2O-TE_soil_probe
 , with a couple minor changes as the probes' data formats are slightly  
different.

When I tell the mote to read from a sensor that's not plugged in, the  
code returns a TIMEOUT error.  When I tell it to read from a sensor  
that is plugged in, it returns an OVERFLOW error.  I tested the buffer  
after the OVERFLOW error, and it appears to be filled with zeros.  (It  
should contain three 2-to-4-digit numbers, in ASCII characters,  
separated by spaces and followed by a CR character.)  Lengthening the  
buffer far past the expected size still produces an OVERFLOW error,  
and the entire buffer is still filled with zeros.  If anyone can  
suggest possible reasons for this, or other tests I could run to find  
more information, I'd greatly appreciate it.

-Kyle

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