Arduino Nano Reset Line

[Wp100]

Hi,

Have a Nano clone board thats powered by an external psu, but sometimes I need to connect it to the pc for data.

As soon as the USB lead is plugged in to the PC the nano Resets.

Seems its the pulse from the DTR line via a 100nf cap from the CH340 Chip to the 328 that causes it.

If I disconnect that 100nf cap it should stop that problem, but wonder what happens with the cap disconnect if I reprogram the nano, will it still work ok ?

Just that on this particular board getting to that cap or any track to make a cut is very difficult, so wanted to ask before doing such a delicate rework.

 

[cowboybob]

This may relate to your issue.

 

[dr pepper]

I have a mega with a defective cap you mentioned, I can program it of I press the reset button just as the programmer tries to upload the program.
Arduino minis dont have a reset cap and require this every program.