While working on an Arduino based project I was suddenly not able to upload sketches using an FTDI anymore. From one minute to another I received errors such as
avrdude: stk500_getsync(): not in sync: resp=0x00 avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51
when trying to upload a sketch to an Arduino Pro Mini or Lilypad.
I checked several possible causes such as
- the COM ports
- the FTDI driver, knowing that FTDI once published a driver that damaged FTDI clones.
- the USB to TTL converter itself
- the Arduino IDE installation
- the bootloader
But the error persisted. None of the possibles causes I checked was responsible.
With the tips in this forum entry I found out that my (original) FTDI chip was the problem, somehow the TX line went dead. Further tests on Linux confirmed this. How and why this happened is unclear.
My final solution? I had to buy a new one…