Good morning, Hope everyone is doing well. I am attempting to stream data to multiple RXs on an on x310. More specifically, I am using TX/RX and RX2 at RFA [0, 1]. I was reviewing the on-line "USRP Hardware Driver and USRP Manual" (https://files.ettus.com/manual/page_stream.html) material. Specifically, the section on "Introduction to Streaming". The authors provide a snippet of code illustrating how to manage a RX streaming for a signal port (below is the python code). import uhd import numpy as np usrp = uhd.usrp.MultiUSRP("type=x300") stream_args = uhd.usrp.StreamArgs("fc32", "sc16") stream_args.args = "spp=200" # Note this setting is not valid for all USRPs rx_streamer = usrp.get_rx_stream(stream_args) rx_metadata = uhd.types.RXMetadata() recv_buffer = np.zeros(rx_streamer.get_max_num_samps(), dtype=np.complex64) stream_cmd = uhd.types.StreamCMD(uhd.types.StreamMode.start_cont) stream_cmd.stream_now = True rx_streamer.issue_stream_cmd(stream_cmd) while run_condition: samps = rx_streamer.recv(recv_buffer, rx_metadata) stream_cmd = uhd.types.StreamCMD(uhd.types.StreamMode.stop_cont) rx_streamer.issue_stream_cmd(stream_cmd) I have attempted to modify the above snippet to support RX streaming into two separate ports on the RFA (TX/RX and RX2 at RFA [0, 1]) and I have not been successful. Below is the error message I am receiving, and I am having trouble deciphering what it's trying to tell me. .... line 207, in main rx_streamer.issue_stream_cmd(uhd.libpyuhd.types.stream_cmd, [0,1]) TypeError: issue_stream_cmd(): incompatible function arguments. The following argument types are supported: 1. (self: uhd.libpyuhd.usrp.rx_streamer, arg0: uhd.libpyuhd.types.stream_cmd) -> None Invoked with: <uhd.libpyuhd.usrp.rx_streamer object at 0x7faf1abc54b0>, <class 'uhd.libpyuhd.types.stream_cmd'>, [0, 1] Is there a snippet of code available that illustrates how to RX Streaming on Multiple Channels? Alternatively, any guidance on how to approach this error message will be very welcomed. Thank you! Regards, AJ Graduate Researcher College of Electrical & Computing Engineering Florida International University 10555 West Flagler Street Room 3863B Miami, FL 33174 Phone: 305-336-2541 | Email: asans008@FIU.edu<mailto:asans008@FIU.edu> [cid:image001.png@01DB9D4B.5689C8A0]

AJ, the error is telling you that you called the issue_stream_cmd() method with invalid arguments. There is no "channel" argument. Instead, the channels are part of the stream command object itself. Do something like this: stream_cmd.channels = [0, 1] # ... rx_streamer.issue_stream_cmd(stream_cmd) Keep in mind that most daughterboards can only receive on one antenna port (exceptions are BasicRX/LFRX and TwinRX, which you are not using). If you are using UBX daughterboards, you get one RX channel from A- and B-side, respectively. --M On Tue, Mar 25, 2025 at 11:24 AM Arnaldo Sans via USRP-users < usrp-users@lists.ettus.com> wrote: > Good morning, > > > > Hope everyone is doing well. I am attempting to stream data to multiple > RXs on an on x310. More specifically, I am using TX/RX and RX2 at RFA [0, > 1]. I was reviewing the on-line “USRP Hardware Driver and USRP Manual” ( > https://files.ettus.com/manual/page_stream.html) material. Specifically, > the section on “*Introduction to Streaming”. *The authors provide a > snippet of code illustrating how to manage a RX streaming for a signal port > (below is the python code). > > > > *import uhd* > > *import numpy as np* > > *usrp = uhd.usrp.MultiUSRP("type=x300")* > > *stream_args = uhd.usrp.StreamArgs("fc32", "sc16")* > > *stream_args.args = "spp=200" # Note this setting is not valid for all > USRPs* > > *rx_streamer = usrp.get_rx_stream(stream_args)* > > *rx_metadata = uhd.types.RXMetadata()* > > *recv_buffer = np.zeros(rx_streamer.get_max_num_samps(), > dtype=np.complex64)* > > *stream_cmd = uhd.types.StreamCMD(uhd.types.StreamMode.start_cont)* > > *stream_cmd.stream_now = True* > > *rx_streamer.issue_stream_cmd(stream_cmd)* > > *while run_condition:* > > *samps = rx_streamer.recv(recv_buffer, rx_metadata)* > > *stream_cmd = uhd.types.StreamCMD(uhd.types.StreamMode.stop_cont)* > > *rx_streamer.issue_stream_cmd(stream_cmd)* > > > > I have attempted to modify the above snippet to support RX streaming into > two separate ports on the RFA (TX/RX and RX2 at RFA [0, 1]) and I have not > been successful. Below is the error message I am receiving, and I am > having trouble deciphering what it’s trying to tell me. > > > > > > *…. line 207, in main* > > * rx_streamer.issue_stream_cmd(uhd.libpyuhd.types.stream_cmd, [0,1])* > > > > *TypeError: issue_stream_cmd(): incompatible function arguments. The > following argument types are supported:* > > * 1. (self: uhd.libpyuhd.usrp.rx_streamer, arg0: > uhd.libpyuhd.types.stream_cmd) -> None* > > > > *Invoked with: <uhd.libpyuhd.usrp.rx_streamer object at 0x7faf1abc54b0>, > <class 'uhd.libpyuhd.types.stream_cmd'>, [0, 1]* > > > > > > Is there a snippet of code available that illustrates how to RX Streaming > on Multiple Channels? Alternatively, any guidance on how to approach this > error message will be very welcomed. > > > > Thank you! > > > > *Regards,* > > *AJ* > > *Graduate Researcher* > > *College of Electrical & **Computing** Engineering * > > *Florida International University* > > *10555 West Flagler Street* > > *Room 3863B* > > *Miami, FL 33174* > > *Phone:* *305-336-2541 |* *Email:* *asans008@FIU.edu <asans008@FIU.edu>* > > > > _______________________________________________ > USRP-users mailing list -- usrp-users@lists.ettus.com > To unsubscribe send an email to usrp-users-leave@lists.ettus.com >