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How I fixed my "programmer is not responding" "not in sync" while attempting to program my Mini Pro

I bought a CP2102 USB - TTL board from eBay. I added the recommended cap from the DTR pin, cut the RST trace, and attached the other end of the cap to the RST pin. I plugged it into my Mini Pro clone, swapping the TX and RX lines as one would think was logical. I got no joy. The arduino IDE would constantly say, either, avrdude: stk500_getsync(): not in sync: resp=0x00 , while in Windows, or, avrdude: stk500_recv(): programmer is not responding , while in Ubuntu.

As many of you have found, lots of people have this issue. There don't seem to be a lot of fixes. I can't promise my experience will work for you, but, hey, it is worth a try. After scanning a number of forum pages, someone mentioned swapping the TX and RX connections. I figured WTH. It can't hurt. I clicked upload, and, IT WORKED! Woohoo!

If you can't program your arduino while using an external USB-TTL board, try swapping the TX and RX connections. 

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We had a PCB engineer who swapped the RX and TX pins because he thought customers were not smart enough to connect RX to TX and vica versa. All he did was confuse the hell out of everyone. He was not as smart as he thought and we had to get rid of him.

It would not surprise me if some other PCB engineers did the same thing. It could have also been an honest mistake.



I have heard of newer things having the labels telling you what they need to be hooked up to, for example, if its labelled TX it goes to the TX on the Arduino. I know that this wasn't the case for the bluetooth module I was working with but I have heard this to happen. 

Then the labels on the programmer must be wrong? Check the datasheet of the CP2102 and follow the traces to the pins (or use a multimeter).

TX of the programmer goes to RX (pin 0) of the Arduino and RX goes to TX (pin 1).

I got no love. I read someone mention the swap, and, BAM it worked.