[LimeSDR-USB] All programs hang on transmit

#1

I just received a new LimeSDR-USB in the mail. Receive works great, but whenever I try to transmit, the LimeSDR just hangs. What I mean by that is, the radio goes into transmit just fine (passing TX calibration if I have enough gain) and a buffer gets filled up, but samples never get drained out of the buffer. For example, here is the output of the basicTX program that ships with LimeSuite:

LimeSuite$ obj-x86_64-linux-gnu/bin/basicTX
Devices found: 1
Reference clock 30.72 MHz
Sample rate: 5 MHz
Center frequency: 500 MHz
Tx tone frequency: 1 MHz
error: samples sent: 6800/8192
TX data rate: 0.008192 MB/s
error: samples sent: 0/8192
TX data rate: 0 MB/s
error: samples sent: 0/8192
TX data rate: 0 MB/s
error: samples sent: 0/8192
TX data rate: 0 MB/s
^C

I get the same behavior with a simple GNU Radio flowgraph using either the Osmo block or the gr-limesdr block, though the buffer size appears to vary depending on which program I use.

I’m using LimeSuite “v18.06.1-1” built from Git revision 2b4e91fd8ecb059f4b8256d63ca1d125cac9f818. Here is the version information from the LimeSDR:

LimeSuite$ LimeUtil --make
Make device 
  Device name: LimeSDR-USB
  Expansion name: UNSUPPORTED
  Firmware version: 4
  Hardware version: 4
  Protocol version: 1
  Gateware version: 2
  Gateware revision: 17
  Gateware target: LimeSDR-USB
  Serial number: 0x9072c02873717
  Free connection... OK
#2

do LimeUtil --find
if it says “media=USB 2.0” then you either have to find a USB 3.0 connection or downgrade your LimeSuite to 18.04.

#3

@yindra Yeah, it’s on USB 2.0. I can’t use USB 3.0 because the connection is not reliable - the LimeSDR stops streaming (receive, at least) after a few minutes of running on USB 3.0.

Is there a bug I can follow for 18.06 to support USB 2.0 again? I can’t downgrade to 18.04 either because I need the calibration fixes in 18.06.

#4

This issue is open:

I never dug into this issue enough to be sure if the issue was in the GW or in the FX3 firmware.


2 Likes
#5

@Zack, is someone taking a look at this?

#6

It is fixed in the latest 18.10 version.

#7

Dear All,

I get a bad behavior about transmit signal with gnu radio. It is nearly similar with you maybe.
My version is : Device name: LimeSDR-USB
Expansion name: UNSUPPORTED
Firmware version: 4
Hardware version: 4
Protocol version: 1
Gateware version: 2
Gateware revision: 21
Gateware target: LimeSDR-USB
Serial number: 0x9081c05c32619
Free connection… OK

In programming section with LimeSuiteGui I uploaded the image 19.4.

when I try to do a quicktest I put frequency central equal to 120Mhz
when I analyzed the spectrum everything seems ok. I was also able to check that the exit was always continuous.
Also when I run basicTX all seem good (data rate is constant)
TX data rate: 20.0335 MB/s
TX data rate: 20.0499 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 19.9557 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 19.9393 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 20.0786 MB/s
TX data rate: 20.0786 MB/s

But when I use gnu radio , I have discontinuity on the output

Have you got one idea?

Best regards

2019-08-15T22:00:00Z