Proxmark3 community

vivat

Contributor

Registered: 2010-10-26

Posts: 332

Peak-detected vs raw multiplexer mode

As I can see, proxmark can switch modes using SetAdcMuxFor(GPIO_MUXSEL_MODE) function. Peak detected mode (GPIO_MUXSEL_LOPKD) and (GPIO_MUXSEL_HIPKD) are being used very often, but I can't find any operation that use RAW mode: SetAdcMuxFor(GPIO_MUXSEL_LORAW) and SetAdcMuxFor(GPIO_MUXSEL_HIRAW).
Let me quote the system design file (../doc/system.txt):

For `slow' signals, I use an MCP6294 opamp. This has a GBW of 10 MHz,
which is more than enough for the low-frequency stuff, and enough for
all of the subcarrier frequencies that I know of at high frequency. In
practice, the `slow' signals are all the signals following the peak
detector. These signals are usually centred around the generated
voltage Vmid.

For `fast' signals, I use an AD8052. This is a very fast voltage-feedback
amplifier (~100 MHz GBW). I use it immediately after the antenna for
both the low- and high-frequency cases, as a sort of an ugly LNA. It is
not optimal, but it certainly made the design easy.

An ordinary CD4066 is used to multiplex the four possible signals
(low/high frequency paths, RAW/PEAK-DETECTED).

So my question is: Have anyone tried to play with raw mode?

VirusVFV

Member

Registered: 2012-11-21

Posts: 4

Re: Peak-detected vs raw multiplexer mode

Hi !
Yesterday I played whith raw mode - no any practical use (at least in mifare snooping mode). I hope that in raw mode I can increase sensitivity of PM3... I was wrong

To do this I changed code in iso1443a.c: (SetAdcMuxFor(GPIO_MUXSEL_HIPKD); -> SetAdcMuxFor(GPIO_MUXSEL_HIRAW);) and recompled the source.
I note as well if U want to use raw mode you may be have to trigger relay on proxmark board. However "hw setmux ..." command does not do that.
To fix this U must change code appmain.c (starting  from "case CMD_SET_ADC_MUX:..." )

vivat

Contributor

Registered: 2010-10-26

Posts: 332

Re: Peak-detected vs raw multiplexer mode

By the way I have noticed that there is only Peak-detected mode on PM3-LCD...
Maybe RAW mode needs more advanced FPGA tweaks than Peak-detected mode?