usrp-users@lists.ettus.com
Discussion and technical support related to USRP, UHD, RFNoC
View all threadsN320 two channel transmit
Hello,
I am trying to use both channels of N320 to transmit the recorded files.
But after a certain times it gives “U” error and stop transmits at that
channel. (The led light of ch0 or ch1 turns off). Then it gives again “U”
error and the other led turns off. Then “L” error occurs. The problem
happens over 20 MSPS of sample rate. Related figures are attached.
Why N320 stops transmitting when “U” error occurs? Isn’t it strange?
There is no problem when transmitting on one channel.
I have intel x520-da2 NIC, i7 8700 processor. I think it shouldn’t be a
problem to transmit at 20 Msps sample rate.
Thanks
Seckin
Hi Seckin,
it's unlikely your processor is the problem here – if anything, it's the 40·10⁶·64b/s ~=
2.4 Gigabit per second that you're reading from your storage from two different files.
Storage devices and file systems have pretty non-deterministic and large-variance read
speeds and access times, and this might be a problem here.
Does this also fail if you just connect two "null sources" instead of "file sources"?
Best regards,
Marcus
DISCLAIMER: Any attached Code is provided As Is. It has not been tested or validated as a product, for use in a deployed application or system, or for use in hazardous environments. You assume all risks for use of the Code. Use of the Code is subject to terms of the licenses to the UHD or RFNoC code with which the Code is used. Standard licenses to UHD and RFNoC can be found at https://www.ettus.com/sdr-software/licenses/.
NI will only perform services based on its understanding and condition that the goods or services (i) are not for the use in the production or development of any item produced, purchased, or ordered by any entity with a footnote 1 designation in the license requirement column of Supplement No. 4 to Part 744, U.S. Export Administration Regulations and (ii) such a company is not a party to the transaction. If our understanding is incorrect, please notify us immediately because a specific authorization may be required from the U.S. Commerce Department before the transaction may proceed further.
On 25.01.22 07:20, Seçkin Öncü wrote:
Hello,
I am trying to use both channels of N320 to transmit the recorded files. But after a
certain times it gives “U” error and stop transmits at that channel. (The led light of
ch0 or ch1 turns off). Then it gives again “U” error and the other led turns off. Then
“L” error occurs. The problem happens over 20 MSPS of sample rate. Related figures are
attached.
Why N320 stops transmitting when “U” error occurs? Isn’t it strange?
There is no problem when transmitting on one channel.
I have intel x520-da2 NIC, i7 8700 processor. I think it shouldn’t be a problem to
transmit at 20 Msps sample rate.
Thanks
Seckin
USRP-users mailing list -- usrp-users@lists.ettus.com
To unsubscribe send an email to usrp-users-leave@lists.ettus.com
Adding to Marcus' comments, if the issue is indeed erratic file reading,
there are a couple of options:
- configure a ram file system and put your transmit files in there
- use the RFNoC Replay block to transmit directly from the FPGA (2GB total
storage). This may be tricky to configure from gnuradio (I've never tried)
On Tue, Jan 25, 2022 at 7:23 AM Marcus Müller marcus.mueller@ettus.com
wrote:
Hi Seckin,
it's unlikely your processor is the problem here – if anything, it's the
40·10⁶·64b/s ~=
2.4 Gigabit per second that you're reading from your storage from two
different files.
Storage devices and file systems have pretty non-deterministic and
large-variance read
speeds and access times, and this might be a problem here.
Does this also fail if you just connect two "null sources" instead of
"file sources"?
Best regards,
Marcus
DISCLAIMER: Any attached Code is provided As Is. It has not been tested or
validated as a product, for use in a deployed application or system, or for
use in hazardous environments. You assume all risks for use of the Code.
Use of the Code is subject to terms of the licenses to the UHD or RFNoC
code with which the Code is used. Standard licenses to UHD and RFNoC can be
found at https://www.ettus.com/sdr-software/licenses/.
NI will only perform services based on its understanding and condition
that the goods or services (i) are not for the use in the production or
development of any item produced, purchased, or ordered by any entity with
a footnote 1 designation in the license requirement column of Supplement
No. 4 to Part 744, U.S. Export Administration Regulations and (ii) such a
company is not a party to the transaction. If our understanding is
incorrect, please notify us immediately because a specific authorization
may be required from the U.S. Commerce Department before the transaction
may proceed further.
On 25.01.22 07:20, Seçkin Öncü wrote:
Hello,
I am trying to use both channels of N320 to transmit the recorded files.
But after a
certain times it gives “U” error and stop transmits at that channel.
(The led light of
ch0 or ch1 turns off). Then it gives again “U” error and the other led
turns off. Then
“L” error occurs. The problem happens over 20 MSPS of sample rate.
Related figures are
attached.
Why N320 stops transmitting when “U” error occurs? Isn’t it strange?
There is no problem when transmitting on one channel.
I have intel x520-da2 NIC, i7 8700 processor. I think it shouldn’t be a
problem to
transmit at 20 Msps sample rate.
Thanks
Seckin
USRP-users mailing list -- usrp-users@lists.ettus.com
To unsubscribe send an email to usrp-users-leave@lists.ettus.com
USRP-users mailing list -- usrp-users@lists.ettus.com
To unsubscribe send an email to usrp-users-leave@lists.ettus.com
Hi Marcus,
-
I connected two null sources and it gave me the same error after 50 seconds at 20 Msps sample rate. This problem occurs in two channels only. After a while it stops transmitting when sample rate >= 20 Msps .
-
When I connected one file or null source, I can use 100 Msps without any error.
On 2022-01-28 05:53, seckinoncu8070@gmail.com wrote:
Hi Marcus,
I connected two null sources and it gave me the same error after
50 seconds at 20 Msps sample rate. This problem occurs in two
channels only. After a while it stops transmitting when sample
rate >= 20 Msps .
When I connected one file or null source, I can use 100 Msps
without any error.
USRP-users mailing list --usrp-users@lists.ettus.com
To unsubscribe send an email tousrp-users-leave@lists.ettus.com
what version of UHD are you using?
What MTU are you using on your 10GiG network link?
I just noticed that you are using "second_addr". My suggestion is to avoid
this unless you need it. A single 10Gbe can handle up to about 250 MS/s
aggregate. So, in your case, one 10Gbe link is sufficient.
Rob
On Fri, Jan 28, 2022 at 10:05 AM Marcus D. Leech patchvonbraun@gmail.com
wrote:
On 2022-01-28 05:53, seckinoncu8070@gmail.com wrote:
Hi Marcus,
-
I connected two null sources and it gave me the same error after 50
seconds at 20 Msps sample rate. This problem occurs in two channels only.
After a while it stops transmitting when sample rate >= 20 Msps .
-
When I connected one file or null source, I can use 100 Msps without
any error.
USRP-users mailing list -- usrp-users@lists.ettus.com
To unsubscribe send an email to usrp-users-leave@lists.ettus.com
what version of UHD are you using?
What MTU are you using on your 10GiG network link?
USRP-users mailing list -- usrp-users@lists.ettus.com
To unsubscribe send an email to usrp-users-leave@lists.ettus.com
UHD 4.1
and MTU = 9000
So, when I want to use the two ports with full capacity, is there always a complication like this?
Could the problem be with the network card( x520-da2)?
On 2022-01-31 01:40, seckinoncu8070@gmail.com wrote:
So, when I want to use the two ports with full capacity, is there
always a complication like this?
Could the problem be with the network card( x520-da2)?
There shouldn't be, but in the interest of debugging, see how far you
can get with two channels into a single interface.
In my experience, it is a significant challenge to get maximum rate Tx
streaming from host to operate without streaming errors. It is much more
challenging than maximum rate Rx Streaming. As a result, when I am using
maximum rates (that would require both 10Gbe links), I always use the Tx
"Replay" block for streaming. I am fortunate that my use case allows a
repetitive signal. So, if you need maximum bandwidth and your use case
allows it, I'd recommend using the Replay block to avoid all Tx
streaming over the link. If your use case does not allow it, you might
want to try the DPDK interface which in my experience performs much better
but with a fairly large hurdle to getting it working. And, in any case, if
your aggregate streaming will fit on a single 10Gbe link (~250MS/s), I
would avoid use of "second_addr". My experience is that for cases where you
don't need it, it is less reliable than a single link (but not sure why).
On Mon, Jan 31, 2022 at 8:35 AM Marcus D. Leech patchvonbraun@gmail.com
wrote:
On 2022-01-31 01:40, seckinoncu8070@gmail.com wrote:
So, when I want to use the two ports with full capacity, is there
always a complication like this?
Could the problem be with the network card( x520-da2)?
There shouldn't be, but in the interest of debugging, see how far you
can get with two channels into a single interface.
USRP-users mailing list -- usrp-users@lists.ettus.com
To unsubscribe send an email to usrp-users-leave@lists.ettus.com