Re: How to use 2 N310 for TX and RX

[Johannes Demel]

Hi,

yes, I just attach a grc file for GR 3.9 that I use to test things.

It works if I specify `addr=...` or `addr0=...` with one device. If I 
switch to 2 devices `addr=....,addr1=...` it fails.

It seems like UHD tries to initialize the devices twice.

----
[INFO] [UHD] linux; GNU C++ version 9.3.0; Boost_107100; 
UHD_3.15.0.0-62-g7a3f1516
[INFO] [MPMD] Initializing 2 device(s) in parallel with args: 
mgmt_addr0=192.168.20.213,type0=n3xx,product0=n310,serial0=319841B,claimed0=False,mgmt_addr1=192.168.21.218,type1=n3xx,product1=n310,serial1=3180AF3,claimed1=False,addr0=192.168.20.213,addr1=192.168.21.218,master_clock_rate=122.88e6,clock_source=external,time_source=external
[INFO] [MPM.PeriphManager] init() called with device args 
`time_source=external,clock_source=external,master_clock_rate=122.88e6,product=n310,mgmt_addr=192.168.20.213'.
[INFO] [0/Replay_0] Initializing block control (NOC ID: 0x4E91A00000000004)
[INFO] [MPM.PeriphManager] init() called with device args 
`time_source=external,product=n310,master_clock_rate=122.88e6,clock_source=external,mgmt_addr=192.168.21.218'.
[INFO] [0/Radio_0] Initializing block control (NOC ID: 0x12AD100000011312)

[...]

[INFO] [1/FIFO_3] Initializing block control (NOC ID: 0xF1F0000000000000)
[INFO] [MULTI_USRP]     1) catch time transition at pps edge
[INFO] [MULTI_USRP]     2) set times next pps (synchronously)
[INFO] [MPMD] Initializing 2 device(s) in parallel with args: 
mgmt_addr0=192.168.20.213,type0=n3xx,product0=n310,serial0=319841B,claimed0=True,mgmt_addr1=192.168.21.218,type1=n3xx,product1=n310,serial1=3180AF3,claimed1=True,addr0=192.168.20.213,addr1=192.168.21.218,master_clock_rate=122.88e6,clock_source=external,time_source=external
[ERROR] [RPC] Someone tried to claim this device again (From: 192.168.20.34)
----

If I use only one device, it looks like this:

----
[INFO] [UHD] linux; GNU C++ version 9.3.0; Boost_107100; 
UHD_3.15.0.0-62-g7a3f1516
[INFO] [MPMD] Initializing 1 device(s) in parallel with args: 
mgmt_addr=192.168.20.213,type=n3xx,product=n310,serial=319841B,claimed=False,addr0=192.168.20.213,master_clock_rate=122.88e6,clock_source=external,time_source=external
[INFO] [MPM.PeriphManager] init() called with device args 
`time_source=external,clock_source=external,master_clock_rate=122.88e6,product=n310,mgmt_addr=192.168.20.213'.
[INFO] [0/Replay_0] Initializing block control (NOC ID: 0x4E91A00000000004)

[...]

[INFO] [0/FIFO_3] Initializing block control (NOC ID: 0xF1F0000000000000)
[INFO] [MULTI_USRP]     1) catch time transition at pps edge
[INFO] [MULTI_USRP]     2) set times next pps (synchronously)
[INFO] [MULTI_USRP]     1) catch time transition at pps edge
[INFO] [MULTI_USRP]     2) set times next pps (synchronously)
----

The last 4 lines are suspicious because they indicate that 
synchronization is performed twice. Also, most of the time during start 
up is spend there.

Anyways, I attached my MWE flowgraph. I'd be happy if you could tell me 
how to fix my issue.

Cheers
Johannes

On 10.02.21 22:52, Marcus D Leech wrote:
> What happens if you just use a single N310 for both TX and RX?
>
> Just trying to figure out where the problem might be. Also please share a 
> minimal flow graph that shows the problem.
>
> Sent from my iPhone
>
> > On Feb 10, 2021, at 1:25 PM, Johannes Demel <demel@ant.uni-bremen.de> wrote:
> >
> > Hi all,
> >
> > I have a flowgraph where I want to use two N310s for TX and RX.
> >
> > If I run `benchmark_rate`, everything works fine.
> >
> > ```
> > ./benchmark_rate --pps external --ref external --rx_channels "0,4" --tx_channels 
> > "2,6" --rx_rate 61.44e6 --tx_rate 61.44e6 
> > --args="addr0=192.168.21.218,addr1=192.168.20.213,master_clock_rate=122.88e6
> > ```
> >
> > It's important that I use one RX and one TX channel each on those USRPs.
> >
> > But it seems like I can't do that with
> >
> > ```
> > [INFO] [UHD] linux; GNU C++ version 9.3.0; Boost_107100; 
> > UHD_3.15.0.0-62-g7a3f1516
> > [INFO] [MPMD] Initializing 2 device(s) in parallel with args: 
> > mgmt_addr0=192.168.20.213,type0=n3xx,product0=n310,serial0=319841B,claimed0=False,mgmt_addr1=192.168.21.218,type1=n3xx,product1=n310,serial1=3180AF3,claimed1=False,addr0=192.168.20.213,addr1=192.168.21.218,master_clock_rate=122.88e6,clock_source=external,time_source=external
> > [INFO] [MPM.PeriphManager] init() called with device args 
> > `time_source=external,clock_source=external,master_clock_rate=122.88e6,product=n310,mgmt_addr=192.168.20.213'.
> > [INFO] [0/Replay_0] Initializing block control (NOC ID: 0x4E91A00000000004)
> > [INFO] [MPM.PeriphManager] init() called with device args 
> > `time_source=external,product=n310,master_clock_rate=122.88e6,clock_source=external,mgmt_addr=192.168.21.218'.
> >
> > [...]
> >
> > [INFO] [MULTI_USRP]     1) catch time transition at pps edge
> > [INFO] [MULTI_USRP]     2) set times next pps (synchronously)
> > [INFO] [MPMD] Initializing 1 device(s) in parallel with args: 
> > mgmt_addr=192.168.21.218,type=n3xx,product=n310,serial=3180AF3,claimed=True,addr=192.168.21.218,master_clock_rate=122.88e6,clock_source=external,time_source=external
> > [ERROR] [RPC] Someone tried to claim this device again (From: 192.168.21.34)
> > [WARNING] [MPM.RPCServer] Someone tried to claim this device again (From: 
> > 192.168.21.34)
> > Traceback (most recent call last):
> >   File "gr-tacmac/examples/usrp_multi_test.py", line 360, in <module>
> >     main()
> >   File "gr-tacmac/examples/usrp_multi_test.py", line 338, in main
> >     tb = top_block_cls()
> >   File "gr-tacmac/examples/usrp_multi_test.py", line 133, in __init__
> >     self.uhd_usrp_sink_0 = uhd.usrp_sink(
> > RuntimeError: RuntimeError: Error during RPC call to `claim'. Error message: 
> > Someone tried to claim this device again (From: 192.168.21.34)
> > ```
> >
> > I can share the example flowgraph. It's just a USRP source connected to a Qt 
> > time sink (and a Qt Freq sink). And a USRP sink that's fed by two Signal 
> > sources.
> >
> > It works if I only have either a USRP sink or USRP source. But in case I try to 
> > use both. The configuration breaks with the above error. How do I fix this?
> >
> > Cheers
> > Johannes

multi_usrp_test.grc
Description: Text document