Looks I have a FTDI USB to TTL adapter that doesn't follow the standard Arduino FTDI pinout order. The chipset is FT232RL and here is the link to Amazon page.


Please can someone tell me the right pinout to connect this to Arduino Pro Mini 3.3v Thanks!

  • 3
    All the pins are clearly labelled, and they are exactly the same as any other FT232 board. Where is the confusion?
    – Majenko
    Apr 13 '19 at 12:31

This is the standard FTDI Basic connections. CTS is an input to the module and is typically just connected to Gnd as seen on the right side here from the Arduino Promini schematic (so the FT232 is always Clear(ed) To Send, i.e. no flow control is used).

DTR may be broken out on one of the side holes. RTS may work for you in place of DTR to create the reset pulse to start the bootloader code. If not, you may have to cut the trace and wire the RTS header pin to DTR. DTR is pin 2 on the FT232, use a meter and confirm it goes to one of the side holes, that way you don't have to try a solder a wire on to a pin.

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  • Thank you @CrossRoads for clearing this up. The DTR was indeed broken out on the side.
    – Arky
    Apr 15 '19 at 6:28

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