hf 14a snoop out of order?

toffe · 2010-04-12 00:09:35

Hi guys,

I've been fiddling about with snooper.c, and figured since it was old commands in it, it was just a matter of updating it to the new command structure. However, I was wrong.

It seems

hf 14a snoop

sometimes manages to get the FPGA to output truckloads of data to the CPU, which causes it to bog down and eventually spit out "blew circular buffer!".

I brought out the oscilloscope and saw the following wave form plotting SSP_CLK + SSP_DIN from the FPGA.
Plot of SSP_CLK (A) and SSP_DIN (B)
This causes the dmaBuf array to be filled with 0xF0 faster than the CPU can process it.

Anyone got an idea of what could cause this to happen?

Last edited by toffe (2010-04-12 00:10:00)

adam@algroup.co.uk · 2010-05-14 15:28:11

I'm getting the same every time I run it, not just 'sometimes':

proxmark3> hf 14a snoop
#db# blew circular buffer! behindBy=0x191
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer! behindBy=0x191
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer! behindBy=0x191
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer! behindBy=0x191
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer! behindBy=0x191
#db# 191 0 0
#db# 20 0 6

I've tried flashing with every archived version I've got, but can't find a rev that works. I guess if we can figure out what rev does work we should be able to see what's changed...

adam@algroup.co.uk · 2010-05-17 21:54:20

OK, this appears to be a bootrom issue. If I regress my pm3 back to the bootrom from rev 338, everything works fine (I didn't even need to re-flash the os/fpga).

Note that rev 338 just happened to be the version I had to hand and tried - there may be later versions which are also OK - I'll now try and figure out exactly which rev broke it...

Jaesik Lee · 2010-05-18 19:05:12

proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6

I also have this problem. (R442. and my system is macbook-ubuntu[no virtual machine])

moh.elsabagh · 2010-05-28 22:09:17

Any updates on that Adam? I am seriously in need for it.

I've a question btw, in the code listing, there's that condition says

if(behindBy > 400) {
  DbpString("blew circular buffer!");
  goto done;
}

Why 400 specifically?

Thanks. PLEASE keep us updated on this issue.

adam@algroup.co.uk · 2010-05-29 13:41:06

I doon't know why 400 specifically - I guess it's as good a number as any...

I haven't had time to look into this further yet, but if you need to get your sniffer back up and running, just load the bootloader from rev 338 for now.

moh.elsabagh · 2010-05-29 14:25:00

Thanks for your reply, but I don't quite know how to regress from the bootloader from the latest revision to the one from rev 338. It will be nice if you could post some instructions on that.

Thanks again.

proxcat · 2010-05-30 12:52:03

You can build osimage.s19/elf from svn r338 the flash it onto the PM3. The bootloader and fpga image should not need to be reflashed.

moh.elsabagh · 2010-05-30 12:58:08

I tried that, but the new flasher tool doesn't work with these images anymore, and the old flasher tool doesn't detect the device since the driver has been changed.

MisterB · 2010-06-15 12:58:02

I have the same problm

proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6
proxmark3> hf 14a snoop
#db# blew circular buffer!
#db# 191 0 0
#db# 20 0 6

I flashed the proxmark with the bootroom 338 and the os of different version but i have the same problem.

Does anyone know the solution ?

Last edited by MisterB (2010-06-15 12:58:30)

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#1 2010-04-12 00:09:35

hf 14a snoop out of order?

#2 2010-05-14 15:28:11

Re: hf 14a snoop out of order?

#3 2010-05-17 21:54:20

Re: hf 14a snoop out of order?

#4 2010-05-18 19:05:12

Re: hf 14a snoop out of order?

#5 2010-05-28 22:09:17

Re: hf 14a snoop out of order?

#6 2010-05-29 13:41:06

Re: hf 14a snoop out of order?

#7 2010-05-29 14:25:00

Re: hf 14a snoop out of order?

#8 2010-05-30 12:52:03

Re: hf 14a snoop out of order?

#9 2010-05-30 12:58:08

Re: hf 14a snoop out of order?

#10 2010-06-15 12:58:02

Re: hf 14a snoop out of order?

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