On 07/25/2018 10:18 PM, RizThon wrote:
I already tried smaller values, but not small enough. It seems the
highest I can go is num_recv_frames=44. Anything higher gives me errors.
At 40MS/s, without that parameter, I get 160 to 180 overflows over 20
seconds, while with num_recv_frames=44 I only get 20 to 30.
This actually allows me to stream at 55MS/s in *sc8* for 20s without
any overflow! With sc16 though, I don't seem much difference and still
get more than 5000 overflows.
Is it possible to use sc12 with the B2x0? The ADC having a 12 bits
resolution, we wouldn't lose any data.
Concerning num_recv_frames, is this a problem with the Windows USB
driver, meaning I wouldn't get better results on another Windows
computer? I tried other drivers, using Zadig. Only the "WinUSB" driver
works, but it doesn't work better than the original Ettus driver.
Do you advise people to use Linux rather than Windows for USB
performance reasons? Should using 256 or 128 fix my streaming problems?
Thanks.
On Thu, Jul 26, 2018 at 2:00 AM Marcus D. Leech <mle...@ripnet.com
<mailto:mle...@ripnet.com>> wrote:
On 07/25/2018 01:08 PM, RizThon wrote:
Use a 5-6V supply capable of 2 or 3 amps.
Thanks, it's actually working fine, the led properly turned green
after the firmware and gateware were uploaded.
Trying .\benchmark_rate.exe --rx_rate 40e6 I get
Benchmark rate summary:
Num received samples: 201778444
Num dropped samples: 2800
Num overruns detected: 2800
Num transmitted samples: 0
Num sequence errors (Tx): 0
Num sequence errors (Rx): 0
Num underruns detected: 0
Num late commands: 0
Num timeouts (Tx): 0
Num timeouts (Rx): 0
It seems I still can't stream faster than around 28MS/s. I still
get similar results with .\rx_samples_to_file.exe (using --null
to not store to file).
Should I try to run some tests from
http://files.ettus.com/manual/page_rdtesting.html ?
Concerning the error "[ERROR] [USB]
libusb_session_impl::libusb_event_handler_task: LIBUSB_ERROR_CODE
-1" that I get when specifying num_recv_frames, what could I do?
Should I try a different driver? Has anyone already experienced
that error?
Thanks.
Try with a smaller number? The Windows LIBUSB behaves
differently than the Linux version. On Linux, I can usually ask
for 256 without
any issue. Try 64.
The SC12 format should work just fine.
The particular values available for num_recv_frames seem to be libusb
implementation specific, and to a certain extent controller specific as
well.
Windows is known to have somewhat poorer performance (at least with
LibUSB type schemes) that Linux, TBH.
_______________________________________________
USRP-users mailing list
USRP-users@lists.ettus.com
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
