power from DTR with avrdude

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Is there a way to make the newer Versions of AVRDUDE to controll the RS232 handshake lines (DTR and RTS) while using a AVR910 programmer ?

I have build a version of the AVR910 programmer, that used optocouplers at the RS232 interface. It used a positive voltage from DTR or RTS lines to power the interface side.
This worked fine with AVRDUDE 4.3 but did not with avrdude 5.0, 5.1 and 5.4.
The old versions had a positive voltage at DTR the new a negative.

As far as I could find in the source code, the handshake lines a set when setting the baudrate. So I am afraid the only solution is change in a future version of avrdude.

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Negative voltage level on DTR is supposed to be the active level,
positive level on RS-232 lines is inactive.

I'm not really aware of which changen in AVRDUDE might have caused
that though.

Jörg Wunsch

Please don't send me PMs, use email if you want to approach me personally.

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The changes probably happend from version 4.3 to 4.4 or 5.0. The main change at that time was getting rid of the cygwin library. In the new source(5.5) the the rs232 parameters are set in ser_win32.c, which is a part that was likely different using cygwin.