Upload sketch through FTDI to Arduino Micro?


is it possible to upload a sketch with a FTDI Breakout Board to the Arduino Micro?
I’m planing a PCB which host the arduino micro, and I would like upload sketches without using the USB connector. So I thought its should be possible to connect the FDTI pins like this:
FTDI breakout < – > Arduino Micro
DTR – Reset
CTS – not connected

But I’m always get the error code
avrdude: stk500_recv(): programmer is not responding

Anyone got an idea or suggestion? I’m also very interested if anyone could get me a suggestion if it could work or not. Is it possible to upload a sketch to a Arduino with the use of a FTDI Breakout Board or another Arduino?

Anyway, I know I could use the USB connector which got a on board FDTI chip connected to the atmega. But I’m looking for a way not to use it.

Thanks for help folks

P.S.: Parts and Software used and tried:

  • OSX 10.7.5 / Windows7
  • Arduino 23, 1.0, 2
  • FDTI Breakout Board - Watterod
  • usb to serial light Adapter - dfrobot
  • Arduino Light Adapter


This doesn't sound right, VIN needs about 7 volts, what voltage do you have on the module's VCC? Also

DTR -- Reset

Must go through a capacitor.

Got a link to the breakout board schematic?


Hi Rob,

I used several Breakout Boards, one is documented here: - http://www.watterott.com/media/files_public/gfyefweedw/FTDI%20Breakout.pdf - http://www.dfrobot.com/index.php?route=product/product&product_id=581#.Uadf-GSAu2E

VIN Then your're right, VIN takes Input Voltage (recommended) 7-12V. I try to power from external supply then..

DTR Found both in the internet, some connected, some not. Didn't understand Why I should connect a capacitor on the line. Any idea what that effect? Anyway, I also try that!


I've never scoped DTR but I assume the pulse on it is too long (or even a constant level) and holds the processor in a reset state for to long. The capacitor is needed to change that to a short pulse to the Arduino's reset signal.

The good news is that it's been implemented on your module according to the schematics, so you don't have to add one yourself.


The DTR pin outputs a level, Reset needs a pulse. The cap is discharged by the DTR level and then recharges from the Reset pullup resistor. Use 0.1uF.

You would have to replace the bootloader to use serial instead of USB on the Micro. Not sure if Optiboot might be made to work with the 32U4.

Good point hiduino, I forgot the Micro has a 32U4.


Yeah, me too. Good catch.

ha! thx hiduino! grrrr also didn't thought about that! So I change the whole layout and will have to plugs, one for pin connection and one usb connection to upload new sketches.

thanks to all!