[TriEmbed] Suggestions Needed to Improve Quality / Reliability

[Pete Soper]

Also, is it a sure thing that the Simblee is pulling the Atmega reset 
line low enough? How much current is the Simblee having to sink to do 
the reset? It might require cutting/repairing a trace, but if the 
current necessary to reset the Atmega could be measured it might show 
this is only working part of the time by serendipity because of a 
problem with the board. We need to be careful to get any regular flux 
off the boards and moisture might create a situation where the Simblee 
hasn't got the grunt to reset the Atmega. If they don't already have 
them your boards may need unique IDs (e.g. a few bytes of the 328's 
EEPROM) to allow for tracking what's going on with them.

There seem to be one or two things that need their root causes found:
   1) Failure to reset ("fugue state")
   2) Atmega "lock up" if it's the cause and not the side effect of (1)

Could the Simblee detect the I2C bus "release" by the Atmega failing and 
tell you exactly when that happens? This might be correlated with 
voltage measurement logs (but you're only logging battery voltage, not 
the IC's VCC, right?) Tacking on a tiny daughterboard to detect and 
signal something to the Simblee would would not be too terrible. In my 
opinion having two processors the way you do is a terrific demonstration 
of the value of postponing optimization. :-)

-Pete