Geeetech

...try forcing it to a different COM port... try 2, 3, or 4

Just a thought.

Re.
G

Yes, when trying to get into DFU mode shorting those pins did not work for me, as the instructions said it would.

RUMBA uses the ATmega16U2 USB Chip ... it does not use the FIDI USB chip. Therefore, it does not good to load those drivers. Where you're getting FIDI from is that some Arduino boards use the FIDI.

The 16U2 chip may have been flashed with the wrong fuse settings... see my thread over at

[ http ...

Looks like I am FINALLY back in business (Knock-On-Wood).

K.I.S.S. method ... EVERYTHING has been done on Win7 x64 boxes at this point. **** Mac OS X has been taking completely out of the loop **** I will report on that with a separate continuation thread. But I've muddled through some things ...

There is something wrong with how OS X communicates with the RUMBA Mega2560 board(s).

I have physical hardware that can dual-boot into Windows 7 and OS X 10.10.4 (tried 10.9.5, 10.10.2 also) from two physically different hard drives.

If I boot into Windows 7 (same physical hardware) ... with ...

...have purchased two boards now. Neither will go into DFU mode.

...OK... so I bought another board directly from You (GeeeTech). It arrived the other day. This board also DOES NOT go into DFU mode.

I need help here, or I need to return BOTH boards and buy something that works and does not have USB connection issues.

Could you please provide step-by-step directions for DFU Mode on a Windows 7 computer ... both jumper technique and avr programming technique. I really need to program the ATmega16u2 with the Rev3 firmware code.

Thanks,
Guy

No... this is not working. I have tried using the jumper approach (as described) ... I have now also purchased a usb avr programmer ...

Jumper Approach:
No LED lights on the ISP Port illuminate using the Jumper GND/RST approach. Only shows up as USB Device COM3, and not USBasp.

AVR Programmer ...

The Rumba board is suppose to be able to use the USB Cable and USB PWR jumped pins and allow for DFU mode. Following the Wiki directions, temporarily shorting the GRN/RST pins only resets the AT16U2, does not put it into DFU mode. DFU Programmer says "No Device Present"

Question #1 - is it possible ...