mini ultra 8hz – arduino IDE not overwriting sketch

[askholme]

Hi

i have an mini ultra 8mhz i bought a while back but never got used.
Now i plugged it in with an FTDI an wanted to use it for a project.

Just to test that it was working i started uploading an old sketch i had with alot of serial debug print.
that worked fine.

But then trouble started as i cannot get rid of that first program. no matter what i create as a sketch it will compile an upload without errors, but in practice the board just keeps running that first program it got.

any idea how i can clear the board?

[LIM PHANG MOH]

That’s odd. Can you show the bottom messages of the Arduino IDE? If, you didn’t enable the verbose output, please do so. There are times, upload just didn’t complete but looks like it is done especially when more warning and errors messages are not enabled.

And how are you powering the board, what FTDI adapter board you are using and is the board type selected as Arduino Pro/ Pro Mini ATMega328P 3.3V 8MHz?

[askholme]

So i did enable verbose output and there was no error messages or similiar.

But i might have discovered the reason – it looks like there is a soldering issue on my FTDI breakout board which potentially means that the DTR and CTS pins have bad or no connection.

As far as i understand various post the DTR pin is used to send a reset signal before starting the programming. I guess a missing reset could be the underlying reason. For the first upload the board would be empty and not require the reset signal but afterwards the upload is effectively discarded because of the missing reset.

I will try to fix the soldering and see if that helps

//Ask

[LIM PHANG MOH]

Yes, you are right. That nails it!
Either DTR or RTS is used and not CTS which is an input pin looking from the FTDI point of view.

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