Hi all,
If you use the latest UHD sources, you should update your ZPU firmware
to the latest version:
http://people.osmocom.org/ipse/umtrx-v2/fpga_bitsream/2013-06-25-2f3817a9/
You could update your FPGA image as well, but ZPU part is critical for
the smooth operation with the latest host side code. If you don't
update ZPU, all UHD utilities will exist on startup. The reason is
that the new host code sends a command to ZPU which older ZPUs does
not understand, so the host side code raises exception and exits.
A new feature which is the reason for the breakage is that now you
could not only set, but also read back the current value of the TCXO
calibration DAC. If you run this utility without any parameters, it
will autodetect UmTRX and read the DAC value from it.
https://github.com/fairwaves/umtrx_scripts/blob/master/python_lib/umtrx_vcx…
This is praticularly useful when you calibrate using GPS and want to
store this value to EEPROM to use it when GPS is not available.
--
Regards,
Alexander Chemeris.
CEO, Fairwaves LLC / ООО УмРадио
http://fairwaves.ru
Hello,
Im an engineer from Spain and Im interested in a GSM receiver because I
would like to study the internal signals for a research project. In
particular, Im interested in the analysis of the IF signal, but, as
Alexander told me, the LMS6002D uses zero-IF architecture, so there is no
real "IF" signal, there is only baseband signal. I guess I could also use
this signal for my purposes, but only if all 124 GSM channels can be found
at that point. Im not sure if this is possible, since there is a low-pass
filter before. Does anybody know if I can extract that information, that is,
the analogic 124 channels after the RF mixer? If it is not possible with
this board, does anybody know if I can do it with another GSM transceiver
board?
Thank you very much in advance.
Best regards,
Albert
Hi All,
I have a project to monitoring ( air sniffer ) the data between GSM BTS and MS using UmTRX.
Uplink Transmission is delayed 3 slots than downlink from specification.
So when I sync. with BTS and get the downlink slot data, I must switch the freqs of receiver from downlink to uplink in less than 2 slots.
When the program call 'usrp_dev->set_rx_freq(wFreq)', How much time does the UmTRX switch to the 'wFreq' ?
Thanks in advance.
Jiang WenYi
Hi Will,
Thank you for the good news. Answering to your question, first please
update your UmTRX firmware and host side UHD:
1. Update your UHD and umtrx_scripts from the git. Build UHD.
2. Flash attached ZPU firmware to a UmTRX with the following command:
./usrp_n2xx_net_burner.py --addr=192.168.10.2 --fw=usrp2p_txrx_uhd.bin
3. Power cycle UmTRX
Calibrate with GPS:
1. Take your UmTRX outside to get GPS lock.
2. When GPS acquires a lock, use 'umtrx_vcxo.py' utility without
parameters to read current VCTCXO DAC value in a loop.
3. When the value stabilise (couple minutes after GPS acquires the
lock), write this value to EEPROM:
./usrp_burn_mb_eeprom --key tcxo-dac --val <YOUR_VAL>
4. Now i should pickup the value from EEPROM on boot, so GPS is no
required unless you change ambient temperature considerably.
Note, that you should warm up your UmTRX for a while before
calibration, because it depends on the TCXO temperature.
Let me know if something goes wrong - I wasn't able to test
everything, as I don't have my UmTRX with me at the moment.
On Tue, May 21, 2013 at 9:50 PM, Will Hawkins
<hawkinsw(a)opentechinstitute.org> wrote:
> Hey Alexander!
>
> Yesterday we took our umtrx outside to get the GPS lock for calibrating the
> tcxo voltage. There were some good outcomes and bad outcomes:
>
> The good:
> If you remember correctly, Dan could not associate to the umtrx with his
> Galaxy Nexus. After getting a GPS signal, Dan's phone could associate! So,
> great news.
>
> The bad:
> We attempted to record the calibrated tcxo dac values and had no luck. We
> booted the umtrx board connected via serial console to my laptop. I was able
> to see the boot messages and other output so I know the console was working.
> Once the board got a GPS lock, I assumed that I would see some tcxo DAC
> values printed to the console. Based on what you said last week, I was going
> to wait until those values stabilized and then use that output to flash into
> the eeprom. Unfortunately I did not see any output on the serial console.
> Then I thought that we could poll the umtrx (using UHD probe) for its tcxo
> dac values. Unfortunately it showed the default (2048) every time.
>
> Can you tell me what I'm doing wrong?
>
> Thanks!
> Will
>
> PS: CC'ing Dan since he's working this with me.
--
Regards,
Alexander Chemeris.
CEO, Fairwaves LLC / ООО УмРадио
http://fairwaves.ru
Hi All,
I wish to work with the Synchronize Sram and to connect it to the FPGA
Microblaze.
Does anyone was able to use and communicate with the SRAM?
If so, can U help with the configuration of the EMC?
I read the EMC datasheet and they describe different way for connecting the
EMC with the SRAM. Maybe U know on a problem when working with SRAM?
thanks in advance,
Yaniv
Hi to All
I am trying to implement Xilinx microblaze on the umtrx2 with EMC core that
connect to the external SRAM. I configured the EMC to Synchronous mode and
I used the UCF that is published at the GITHUB. If I am trying to deluge
the MCU without the EMC the MCU seem running, but when I connect the EMC,
the MCU stuck and I cannot download the code through the JTAG.
Please advise how to connect the EMC core to the external SRAM ?
thanks in advance,
Yaniv
Hello team,
I met in Paris with Jean-Samuel last Friday. We talked among other
things about handover in OpenBTS and I wanted to share some of our ideas
with you.
Note: this is my recollection of things, if I misreported something it's
my fault. :}
# Handling SIP intricacies outside of OpenBTS
We both agreed that it is better/simpler to keep the complexity of SIP
protocol out of OpenBTS. There are already very good platforms that can
hide the intricacies of SIP from OpenBTS (FreeSwitch, Asterisk, OpenSIPS
B2BUA, etc.). The alternative (implementing a complete, compliant B2BUA
SIP stack inside OpenBTS) seems difficult (complete rewrite using e.g.
sofia-sip) and doesn't help with time-to-market.
We also both enjoy the "GSM handset looks like a SIP endpoint" analogy
that is the basis of OpenBTS and would like to keep the OpenBTS
GSM-to-SIP interface as transparent as possible.
(Apologies for cross-posting. We wanted to reach everyone who might be
interested in attending. Please respond responsibly.)
Anders Brownworth (Switchcoder), Alexander Chemeris (Fairwaves), and Robin
Coxe (Close-Haul Communications & Analog Devices) invite those interested
in open GSM hardware and software development to an informal gathering in
Cambridge, MA on Friday 10 May 2013 from 6-8 pm. Alexander will be
visiting the Boston area from Moscow.
If you are interested in participating in any capacity in the Boston-area
open source GSM development community, we look forward to meeting you. Our
goal is to identify like-minded people involved in or interested in
learning more about projects such as OpenBTS, OsmocomBTS, OsmocomBB, and
OpenBSC. If you have a portable, self-contained demo, feel free to bring
it with you.
When: Friday 10 May 2013, 6-8 pm EDT
Where: Cambridge Innovation Center, 1 Broadway, 4th Floor, Cambridge, MA
02142 USA
Photo ID required for building entry.
Please RSVP on Eventbrite: http://opengsmboston.eventbrite.com/
Hello,
I was wondering whether there is an FPGA image for the UmTRX which gives 4x
DDC Rx chains (at the expense of the two DUC chains) like the USRP1
usrp1_fpga_4rx.rbf. I guess this is unlikely, due to the fact it looks like
the majority of people are using the UmTRX for OpenBTS! How difficult would
it be to change the current firmware to support this.
Another couple of questions, what's the maximum achievable bandwidth
through a single Rx chain so far and are there any constraints on what
value of decimation to use (e.g. USRP has the requirement that to use both
CIC filters decimation factors have to be a factor of 4, otherwise the
frequency response will be affected)? When I increase the sample rate (e.g.
4.333 MHz) I start seeing the frequency response affected, the FFT plot
seems to 'flicker' between a reasonably flat looking response and a poor
frequency response (see attached files - both taken from the same running
instance of a flow graph)
Cheers,
John
--
*Dr. John Wilson*
Product development engineer, Path
Intelligence<http://www.pathintelligence.com/>
T +44 2392 388442 @pathintel
DETECT • ANALYSE • PREDICT • INFLUENCE
Path Intelligence Limited, registered number 5176274. Registered in
England,
registered office at 1000 Lakeside North Harbour, Western Road, Portsmouth,
UK, PO6 3EN
