user37429: I have wired my Arduino as seen in the picture, with the RX of the cable plugged into the TX (D1) of the Leonardo and the TX of the cable plugged into the RX(D0) of the Leonardo. I then have the ground plugged into GND and the power into 5V. The driver is installed correctly and the IDE recognizes the port, however, whenever I try and upload any sketch, I get the error:
Programmer Type : butterfly
         Description     : Atmel AppNote AVR109 Boot Loader
Connecting to programmer: .avrdude: butterfly_recv(): programmer is not responding
avrdude: butterfly_recv(): programmer is not responding
I can upload sketches fine via usb, is it just unable to do so via a USB to TTL cable?

Thanks in advance

user4143: The bootloader on the Leonardo operates through the native USB port of the ATMega32U2 chip, not the UART.
You cannot treat it like an Uno because it isn't an Uno.
You can only program it through the USB port or through the ICSP connector.
If you want to use UART to upload you will need to replace the bootloader with a suitable UART based alternative. (Before you ask, no I don't know if one even exists or where to get it if it does).

37429: <p>I have wired my Arduino as seen in the picture, with the RX of the cable plugged into the TX (D1) of the Leonardo and the TX of the cable plugged into the RX(D0) of the Leonardo. I then have the ground plugged into GND and the power into 5V. The driver is installed correctly and the IDE recognizes the port, however, whenever I try and upload any sketch, I get the error:</p>

<p>Programmer Type : butterfly
         Description     : Atmel AppNote AVR109 Boot Loader</p>

<p>Connecting to programmer: .avrdude: butterfly_recv(): programmer is not responding</p>

<p>avrdude: butterfly_recv(): programmer is not responding</p>

<p>I can upload sketches fine via usb, is it just unable to do so via a USB to TTL cable?</p>

<p><a href="https://i.stack.imgur.com/OYJD7.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OYJD7.jpg" alt="enter image description here"></a></p>

<p>Thanks in advance</p>
 4143: <p>The bootloader on the Leonardo operates through the native USB port of the ATMega32U2 chip, not the UART.</p>

<p>You cannot treat it like an Uno because it isn't an Uno.</p>

<p>You can only program it through the USB port or through the ICSP connector.</p>

<p>If you want to use UART to upload you will need to replace the bootloader with a suitable UART based alternative. (Before you ask, no I don't know if one even exists or where to get it if it does).</p>
