I understand the what the the auto reset feature is and what it is used for. However Every time a new USB device ( any device ) is plugged into the USB bus it triggers one of these auto resets. I've tried this on 2 XP machines and one windows 2000 and they all did this. However when I tried this on a Mac there was no auto reset. I did not think that this is the correct behavior, is it?
Is this a driver issue?
Is this operating system setting?
This is very inconvenient for my project!
Thanks
Humm, interesting question and symptom. As a quick test I fired up my mega board and had it running blink. If I open or close the serial monitor function it of course resets each time. However if I turn on my USB printer I see no reset. Running XP sp3.
Anyone else able to reconstruct the symptom?
Lefty
Ok I seem to have figured it out.
I did a little research and found that if the Serial Enumerator setting was checked in the FTDI driver, then the control lines toggle whenever a new device appears on the same hub. This is what was toggling the the DTR line and causing the reset.
In order to get the setting to take I had to uncheck the Serial Enumerator option ( which was under the device manager -> USB Serial Port driver properties-> port setting ->advanced )then unplug and replug my Arduino.
I'm kinda surprised that no one has seen this before being that this was the default settings of the FTDI driver for the three windows machines that I tried this on?
Thanks moorecj. I saw that option before, but the documentation was confusing, so I didnt bother.
I agree, it is really annoying when it resets every time the USB bus does an enumeration.