Proxmark3 community

duran97

Contributor

Registered: 2009-06-16

Posts: 63

Flashing the firmware

OK, dumb question time (and yes I have read the manual).  Having had a Proxmark 3 for over a year, I've finally found some time to play with it - sad I know. I want to double check the flashing of the firmware, as I really don't want to go back to getting the firmware back on via JTAG.

To flash the firmware from the original, I presume I need to load the new bootrom, the new fpga and the new osimage. Do I have to run the commands twice for each, or is that only for the osimage?

TomBu

Contributor

From: Delft, The Netherlands

Registered: 2008-10-27

Posts: 55

Website

Re: Flashing the firmware

Here's a quote from the Manual, which can be found here:
https://www.lafargue.name/article2752.html

How to upgrade the firmware

As described earlier, the Proxmark firmware comprises a bootloader, a fpga image and actual OS, i.e. the ARM code. This firmware can be upgraded through USB, this is a feature of the bootloader. Depending on the firmware version, you can either upgrade the bootloader or the fpga+os (original firmware), or upgrade bootloader, fpga image and os separately (20081211 version).

In the normal course of operations, there is no reason why you should need to use the JTAG connector that is installed on the Proxmark, unless you somehow manage to crash the bootloader itself when flashing it over USB.

Actual flashing of the proxmark involves issuing flash commands twice : the first attempt causes the device to reboot, and then a second time where actual flashing takes place :

#prox load osimage.s19
-- error, then the device reboots --
#prox load osimage.s19
-- actual flashing takes place
Note : this double command is not necessary for current versions of the firmware, as described below :

Note for 20081211 version and later : flashing can only be done with the proxmark button pressed down when the proxmark is plugged in, as described in the ’CHANGES.TXT’ file in the ’doc’ directory that comes in the 20081211 zipfile.

With this boot code, the device can now only be flashed if button is held down after power on or a software reset.

The flash procedure is this :

Hold down button. Either plug in USB or software reset it. _While_holding_down_button_ (red and yellow LEDs are lit) you can issue one or more of the "prox bootrom " "prox fpga " "prox load ", be sure to hold button down for the entire duration of the flash process. Only release the button when flashing is complete and you want to let the board boot.

This process may be less convenient but it’s safer and avoids "unintentional" flashing of the board.

Linux & VMWare : thanks to the new flashing mode (keeping the button pressed), it now is fairly simple & reliable to flash the Proxmark3 from a Windows XP guest on a Linux host using vmware : just make sure your virtual machine is configured to automatically grab USB devices when it has focus and don’t forget to keep the Proxmark3 button pressed when you connect it to the USB port.

So if you have a newer version of FW already installed you don't even need to do the command twice.
You just have to press the button while rebooting....

BTW, AFAIK there's no harm in giving the command twice, regardless of what part of the firmware. So why not? Better safe then sorry.

Cheers,
Tom

duran97

Contributor

Registered: 2009-06-16

Posts: 63

Re: Flashing the firmware

Cheers TomBU.  I had read that, but wasn't sure abot the other parts of the firmware. If it's not going to do any harm (which I can't see why it would), I might as well do it to be sure.