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Author Topic: Serial Monitor and Reboot  (Read 699 times)
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Why does the Arduino reboot when I access its serial output with Serial Monitor or HyperTerminal, but not with Termite ?   (see http://www.compuphase.com/software_termite.htm)

I haven't tried any other terminal programs.

If some command from the HyperTerminal (but not Termite) is making the Arduino reboot, then does that not suggest that there should be some way of making the Arduino reboot programatically (from within a sketch) ?  I have not seen how to do this.  Some of my Arduinos run continuously over very long periods, and it might be nice it they could reboot themselves periodically.

Thank you.
Bob W
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When the "serial port" is opened, RTS and DTR are asserted, causing the board to reset.

Some terminal programs have enough "serial port control" to not assert these signals.
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Some of my Arduinos run continuously over very long periods, and it might be nice it they could reboot themselves periodically.

Rebooting programmatically is not too hard using the WDT as the source of rebooting reset signal.

 Also it's not too hard to prevent rebooting caused by PC applications opening/closing the USB serial connection by just defeating the auto-reset function on the board once the sketch is loaded. A 10 ufd cap wired from the reset pin to a ground pin should do that.

Lefty
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Ah huh, that answers my first question - thanks James!

I've noticed on my project that the Serial Monitor seems to 'lock up' after a while - no more output prints.  Closing/opening the Serial Monitor resolves the problem, although I see now that is because the board resets (and explains why the TCP port resets back to 1025!). 

Don't mean to get too off-topic from Bob's original query, but is that an issue in the Arduino IDE (1.0.3) that anyone else has seen, or should I look more at the hardware I'm using (Freetronics EtherMega)?  I can see the board is still working via Wireshark trace but the Serial Monitor stops updating.

Thanks.

Brett.
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More likely a bug. Raise an issue in the Programming section, posting your code.
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