[USRP-users] Different streaming modes at the same time with same USRP hardware

Felipe Augusto Pereira de Figueiredo zz4fap at gmail.com
Fri Jul 7 17:58:32 EDT 2017


Thanks Michael!

Now I'm trying to create different streamers for TX and RX in channels
0 and 1, but my application running on a b210 returns the following
error:

Error opening RX stream for channel 1 with error code: 44
No compatible RF frontend found
Error opening rf

I checked and code 44 means UHD_ERROR_RUNTIME.

The most strange thing is that with a x310 the same code (see code
below) works. The code I sent previously to you runs with both b210
and x310 USRPs, however, it only creates/configures RX streamers.

What could be the reason for this different behaviour? Is there a
sequence for creating and setting TX and RX streamers for channels 0
and 1?

Thanks and Kind Regards,

Felipe Augusto

   /* Find available devices */
    uhd_string_vector_handle devices_str;
    uhd_string_vector_make(&devices_str);
    uhd_usrp_find("", &devices_str);

    char args2[512];

    handler->dynamic_rate = true;

    // Allow NULL parameter
    if (args == NULL) {
      args = "";
    }
    handler->devname = NULL;

    // Initialize handler
    handler->uhd_error_handler = NULL;

    /* If device type or name not given in args, choose a B200 */
    if (args[0]=='\0') {
      if (find_string(devices_str, "type=b200") && !strstr(args,
"recv_frame_size")) {
        // If B200 is available, use it
        args = "type=b200";
        handler->devname = DEVNAME_B200;
      } else if (find_string(devices_str, "type=x300")) {
        // Else if X300 is available, set master clock rate now (with
x310 it can't be changed later)
        args = "type=x300,master_clock_rate=184.32e6";// If no
argument is passed we set master clock rate to 184.32 MHz in order to
use standard LTE rates, i.e., carrier sepration of 15 KHz.
        //args = "type=x300,master_clock_rate=200e6"; // In case we
need longer CP periods, we should set master clock rate to 200 MHz in
order to be able to set the sampling rate to 5 MHz and have bigger
CPs.
        handler->dynamic_rate = false;
        handler->devname = DEVNAME_X300;
      }
    } else {
      // If args is set and x300 type is specified, make sure
master_clock_rate is defined
      if (strstr(args, "type=x300") && !strstr(args, "master_clock_rate")) {
        sprintf(args2, "%s,master_clock_rate=184.32e6",args);
        args = args2;
        handler->dynamic_rate = false;
        handler->devname = DEVNAME_X300;
      } else if (strstr(args, "type=b200")) {
        handler->devname = DEVNAME_B200;
      }
    }

    uhd_string_vector_free(&devices_str);

    /* Create UHD handler */
    printf("Opening USRP with args: %s\n", args);
    uhd_error error = uhd_usrp_make(&handler->usrp, args);
    if (error) {
      fprintf(stderr, "Error opening UHD: code %d\n", error);
      return -1;
    }

    if (!handler->devname) {
      char dev_str[1024];
      uhd_usrp_get_mboard_name(handler->usrp, 0, dev_str, 1024);
      if (strstr(dev_str, "B2") || strstr(dev_str, "B2")) {
        handler->devname = DEVNAME_B200;
      } else if (strstr(dev_str, "X3") || strstr(dev_str, "X3")) {
        handler->devname = DEVNAME_X300;
      }
    }
    if (!handler->devname) {
      handler->devname = "uhd_unknown";
    }

    // Set external clock reference
    if (strstr(args, "clock=external")) {
      uhd_usrp_set_clock_source(handler->usrp, "external", 0);
    }

    // ************* Initialize Channes 0 and 1. *************
    size_t channels[2] = {0,1};
    uhd_stream_args_t stream_args = {
      .cpu_format = "fc32",
      .otw_format = "sc16",
      .args = "",
      .channel_list = channels,
      .n_channels = 2
    };

    // Stream args for channels 0 and 1
    for(size_t channel = 0; channel < 2; channel++) {

      handler->channels[channel].has_rssi = get_has_rssi(handler, channel);
      if (handler->channels[channel].has_rssi) {
        uhd_sensor_value_make_from_realnum(&handler->channels[channel].rssi_value,
"rssi", 0, "dBm", "%f");
      }

      /* Initialize RX and TX streamers */
      uhd_rx_streamer_make(&handler->channels[channel].rx_stream);
      stream_args.channel_list = &channels[channel];
      stream_args.n_channels = 1;
      error = uhd_usrp_get_rx_stream(handler->usrp, &stream_args,
handler->channels[channel].rx_stream);
      if (error) {
        fprintf(stderr, "Error opening RX stream for channel %d with
error code: %d\n",channel, error);
        return -1;
      }
      uhd_tx_streamer_make(&handler->channels[channel].tx_stream);
      error = uhd_usrp_get_tx_stream(handler->usrp, &stream_args,
handler->channels[channel].tx_stream);
      if (error) {
        fprintf(stderr, "Error opening TX stream: %d\n", error);
        return -1;
      }

      uhd_rx_streamer_max_num_samps(handler->channels[channel].rx_stream,
&handler->channels[channel].rx_nof_samples);
      uhd_tx_streamer_max_num_samps(handler->channels[channel].tx_stream,
&handler->channels[channel].tx_nof_samples);

      uhd_meta_range_make(&handler->channels[channel].rx_gain_range);
      uhd_usrp_get_rx_gain_range(handler->usrp, "", channel,
handler->channels[channel].rx_gain_range);

      // Make metadata objects for RX/TX.
      uhd_rx_metadata_make(&handler->channels[channel].rx_md);
      uhd_rx_metadata_make(&handler->channels[channel].rx_md_first);
      uhd_tx_metadata_make(&handler->channels[channel].tx_md, false,
0, 0, false, false);
    }

On Fri, Jul 7, 2017 at 11:32 PM, Michael West <michael.west at ettus.com> wrote:
> Hi Felipe,
>
> If it works, it must be right!  The code looks fine to me.
>
> Regards,
> Michael
>
> On Mon, Jul 3, 2017 at 3:58 AM, Felipe Augusto Pereira de Figueiredo
> <zz4fap at gmail.com> wrote:
>>
>> Dear Michael,
>>
>> I've followed your suggestion and hacked the rx_samples_c.c example.
>> It seems to be working but I'm not sure if that is the right way of doing
>> that.
>> Could you please have a quick look and tell me if that is the correct way
>> of creating 2 different RX streams.
>>
>> Thanks and Kind Regards,
>>
>> Felipe Augusto
>>
>> /*
>>  * Copyright 2015 Ettus Research LLC
>>  *
>>  * This program is free software: you can redistribute it and/or modify
>>  * it under the terms of the GNU General Public License as published by
>>  * the Free Software Foundation, either version 3 of the License, or
>>  * (at your option) any later version.
>>  *
>>  * This program is distributed in the hope that it will be useful,
>>  * but WITHOUT ANY WARRANTY; without even the implied warranty of
>>  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>>  * GNU General Public License for more details.
>>  *
>>  * You should have received a copy of the GNU General Public License
>>  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
>>  */
>>
>> #include <uhd.h>
>>
>> #include "getopt.h"
>>
>> #include <stdio.h>
>> #include <stdlib.h>
>> #include <string.h>
>>
>> #define EXECUTE_OR_GOTO(label, ...) \
>>     if(__VA_ARGS__){ \
>>         return_code = EXIT_FAILURE; \
>>         goto label; \
>>     }
>>
>> void print_help(void){
>>     fprintf(stderr, "rx_samples_c - A simple RX example using UHD's C
>> API\n\n"
>>
>>                     "Options:\n"
>>                     "    -a (device args)\n"
>>                     "    -f (frequency in Hz)\n"
>>                     "    -r (sample rate in Hz)\n"
>>                     "    -g (gain)\n"
>>                     "    -n (number of samples to receive)\n"
>>                     "    -o (output filename, default = \"out.dat\")\n"
>>                     "    -v (enable verbose prints)\n"
>>                     "    -h (print this help message)\n");
>> };
>>
>> int main(int argc, char* argv[])
>> {
>>     if(uhd_set_thread_priority(uhd_default_thread_priority, true)){
>>         fprintf(stderr, "Unable to set thread priority. Continuing
>> anyway.\n");
>>     }
>>
>>     int option = 0;
>>     double freq = 2.4e9;
>>     double rate = 10e6;
>>     double gain = 5.0;
>>     char* device_args = "";
>>     size_t channel[2] = {0,1};
>>     char *filename0 = "out0.dat", *filename1 = "out1.dat";
>>     size_t n_samples = 1000000;
>>     bool verbose = false;
>>     int return_code = EXIT_SUCCESS;
>>     bool custom_filename0 = false, custom_filename1 = false;
>>     char error_string[512];
>>
>>     // Process options
>>     while((option = getopt(argc, argv, "a:f:r:g:n:o:O:vh")) != -1){
>>         switch(option){
>>             case 'a':
>>                 device_args = strdup(optarg);
>>                 break;
>>
>>             case 'f':
>>                 freq = atof(optarg);
>>                 break;
>>
>>             case 'r':
>>                 rate = atof(optarg);
>>                 break;
>>
>>             case 'g':
>>                 gain = atof(optarg);
>>                 break;
>>
>>             case 'n':
>>                 n_samples = atoi(optarg);
>>                 break;
>>
>>             case 'o':
>>                 filename0 = strdup(optarg);
>>                 custom_filename0 = true;
>>                 break;
>>
>>             case 'O':
>>                 filename1 = strdup(optarg);
>>                 custom_filename1 = true;
>>                 break;
>>
>>             case 'v':
>>                 verbose = true;
>>                 break;
>>
>>             case 'h':
>>                 print_help();
>>                 goto free_option_strings;
>>
>>             default:
>>                 print_help();
>>                 return_code = EXIT_FAILURE;
>>                 goto free_option_strings;
>>         }
>>     }
>>
>>     // Create USRP
>>     uhd_usrp_handle usrp;
>>     fprintf(stderr, "Creating USRP with args \"%s\"...\n", device_args);
>>     EXECUTE_OR_GOTO(free_option_strings,
>>         uhd_usrp_make(&usrp, device_args)
>>     )
>>
>>     // Create RX streamer #0.
>>     uhd_rx_streamer_handle rx_streamer0;
>>     EXECUTE_OR_GOTO(free_usrp,
>>         uhd_rx_streamer_make(&rx_streamer0)
>>     )
>>
>>     // Create RX metadata #0.
>>     uhd_rx_metadata_handle md0;
>>     EXECUTE_OR_GOTO(free_rx_streamer0,
>>         uhd_rx_metadata_make(&md0)
>>     )
>>
>>     // Create RX streamer #1.
>>     uhd_rx_streamer_handle rx_streamer1;
>>     EXECUTE_OR_GOTO(free_usrp,
>>         uhd_rx_streamer_make(&rx_streamer1)
>>     )
>>
>>     // Create RX metadata #1.
>>     uhd_rx_metadata_handle md1;
>>     EXECUTE_OR_GOTO(free_rx_streamer1,
>>         uhd_rx_metadata_make(&md1)
>>     )
>>
>>     // Create other necessary structs
>>     uhd_tune_request_t tune_request = {
>>         .target_freq = freq,
>>         .rf_freq_policy = UHD_TUNE_REQUEST_POLICY_AUTO,
>>         .dsp_freq_policy = UHD_TUNE_REQUEST_POLICY_AUTO,
>>     };
>>     uhd_tune_result_t tune_result;
>>
>>     uhd_stream_args_t stream_args = {
>>         .cpu_format = "fc32",
>>         .otw_format = "sc16",
>>         .args = "",
>>         .channel_list = &channel,
>>         .n_channels = 2
>>     };
>>
>>     size_t samps_per_buff0, samps_per_buff1;
>>     float *buff0 = NULL, *buff1 = NULL;
>>     void **buffs_ptr0 = NULL, **buffs_ptr1 = NULL;
>>     FILE *fp0 = NULL, *fp1 = NULL;
>>     size_t num_acc_samps0 = 0, num_acc_samps1 = 0;
>>
>>     // Set rate for stream #0
>>     fprintf(stderr, "Setting RX Rate 0: %f...\n", rate);
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_set_rx_rate(usrp, rate, channel[0])
>>     )
>>
>>     // Set rate for stream #1
>>     // Stream number 1 should have a different sampling rate.
>>     rate = 2*rate;
>>     fprintf(stderr, "Setting RX Rate 1: %f...\n", rate);
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_set_rx_rate(usrp, rate, channel[1])
>>     )
>>
>>     // See what rate is actually set for stream #0
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_get_rx_rate(usrp, channel[0], &rate)
>>     )
>>     fprintf(stderr, "Actual RX Rate 0: %f...\n", rate);
>>
>>     // See what rate is actually set for stream #1
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_get_rx_rate(usrp, channel[1], &rate)
>>     )
>>     fprintf(stderr, "Actual RX Rate 1: %f...\n", rate);
>>
>>     // Set gain for stream #0
>>     fprintf(stderr, "Setting RX Gain 0: %f dB...\n", gain);
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_set_rx_gain(usrp, gain, channel[0], "")
>>     )
>>
>>     // Set gain for stream #1
>>     fprintf(stderr, "Setting RX Gain 1: %f dB...\n", gain);
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_set_rx_gain(usrp, gain, channel[1], "")
>>     )
>>
>>     // See what gain is actually set for stream #0
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_get_rx_gain(usrp, channel[0], "", &gain)
>>     )
>>     fprintf(stderr, "Actual RX Gain 0: %f...\n", gain);
>>
>>     // See what gain is actually set for stream #1
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_get_rx_gain(usrp, channel[1], "", &gain)
>>     )
>>     fprintf(stderr, "Actual RX Gain 1: %f...\n", gain);
>>
>>     // Set frequency for stream #0
>>     fprintf(stderr, "Setting RX frequency 0: %f MHz...\n", freq/1e6);
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_set_rx_freq(usrp, &tune_request, channel[0],
>> &tune_result)
>>     )
>>
>>     // Set frequency for stream #1
>>     freq = 3e9;
>>     tune_request.target_freq = freq;
>>     fprintf(stderr, "Setting RX frequency 1: %f MHz...\n", freq/1e6);
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_set_rx_freq(usrp, &tune_request, channel[1],
>> &tune_result)
>>     )
>>
>>     // See what frequency is actually set fro stream #0
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_get_rx_freq(usrp, channel[0], &freq)
>>     )
>>     fprintf(stderr, "Actual RX frequency 0: %f MHz...\n", freq / 1e6);
>>
>>     // See what frequency is actually set fro stream #1
>>     EXECUTE_OR_GOTO(free_rx_metadata,
>>         uhd_usrp_get_rx_freq(usrp, channel[1], &freq)
>>     )
>>     fprintf(stderr, "Actual RX frequency 1: %f MHz...\n", freq / 1e6);
>>
>>     // Set up streamer #0.
>>     printf("Try to get RX Stream #0\n");
>>     stream_args.channel_list = &channel[0];
>>     stream_args.n_channels = 1;
>>     EXECUTE_OR_GOTO(free_rx_streamer0,
>>         uhd_usrp_get_rx_stream(usrp, &stream_args, rx_streamer0)
>>     )
>>     printf("Got RX Stream #0\n");
>>
>>     // Set up streamer #1.
>>     printf("Try to get RX Stream #1\n");
>>     stream_args.channel_list = &channel[1];
>>     stream_args.n_channels = 1;
>>     EXECUTE_OR_GOTO(free_rx_streamer1,
>>         uhd_usrp_get_rx_stream(usrp, &stream_args, rx_streamer1)
>>     )
>>     printf("Got RX Stream #1\n");
>>
>>     // Set up buffer for stream #0.
>>     EXECUTE_OR_GOTO(free_rx_streamer0,
>>        uhd_rx_streamer_max_num_samps(rx_streamer0, &samps_per_buff0)
>>     )
>>     printf("Buffer size in samples for stream #0: %zu\n",
>> samps_per_buff0);
>>     buff0 = malloc(samps_per_buff0 * 2 * sizeof(float));
>>     buffs_ptr0 = (void**)&buff0;
>>
>>     // Set up buffer for stream #1.
>>     EXECUTE_OR_GOTO(free_rx_streamer1,
>>        uhd_rx_streamer_max_num_samps(rx_streamer1, &samps_per_buff1)
>>     )
>>     printf("Buffer size in samples for stream #1: %zu\n",
>> samps_per_buff1);
>>     buff1 = malloc(samps_per_buff1 * 2 * sizeof(float));
>>     buffs_ptr1 = (void**)&buff1;
>>
>>     // Stream command for stream #0.
>>     uhd_stream_cmd_t stream_cmd0 = {
>>         .stream_mode = UHD_STREAM_MODE_NUM_SAMPS_AND_DONE,
>>         .num_samps = n_samples,
>>         .stream_now = false,
>> .time_spec_full_secs = 2,
>> .time_spec_frac_secs = 0
>>     };
>>
>>     // Issue stream command for stream #0.
>>     fprintf(stderr, "Issuing stream command for stream #0.\n");
>>     EXECUTE_OR_GOTO(free_buffer0,
>>         uhd_rx_streamer_issue_stream_cmd(rx_streamer0, &stream_cmd0)
>>     )
>>
>>     // Stream command for stream #1.
>>     uhd_stream_cmd_t stream_cmd1 = {
>>         .stream_mode = UHD_STREAM_MODE_NUM_SAMPS_AND_DONE,
>>         .num_samps = n_samples,
>>         .stream_now = false,
>> .time_spec_full_secs = 4,
>> .time_spec_frac_secs = 0
>>     };
>>
>>     // Issue stream command for stream #1.
>>     fprintf(stderr, "Issuing stream command for stream #1.\n");
>>     EXECUTE_OR_GOTO(free_buffer1,
>>         uhd_rx_streamer_issue_stream_cmd(rx_streamer1, &stream_cmd1)
>>     )
>>
>>     // Set up file output for stream #0.
>>     fp0 = fopen(filename0, "wb");
>>
>>     // Set up file output for stream #1.
>>     fp1 = fopen(filename1, "wb");
>>
>>     // Actual streaming
>>     while (num_acc_samps0 < n_samples) {
>>         size_t num_rx_samps0 = 0;
>>         EXECUTE_OR_GOTO(close_file0,
>>             uhd_rx_streamer_recv(rx_streamer0, buffs_ptr0,
>> samps_per_buff0, &md0, 3.0, false, &num_rx_samps0)
>>         )
>>
>>         size_t num_rx_samps1 = 0;
>>         EXECUTE_OR_GOTO(close_file1,
>>             uhd_rx_streamer_recv(rx_streamer1, buffs_ptr1,
>> samps_per_buff1, &md1, 3.0, false, &num_rx_samps1)
>>         )
>>
>>         uhd_rx_metadata_error_code_t error_code0;
>>         EXECUTE_OR_GOTO(close_file0,
>>             uhd_rx_metadata_error_code(md0, &error_code0)
>>         )
>>         if(error_code0 != UHD_RX_METADATA_ERROR_CODE_NONE){
>>             fprintf(stderr, "Error code 0x%x was returned during
>> streaming. Aborting: 0x%x.\n", return_code,error_code0);
>>             goto close_file0;
>>         }
>>
>>         uhd_rx_metadata_error_code_t error_code1;
>>         EXECUTE_OR_GOTO(close_file1,
>>             uhd_rx_metadata_error_code(md1, &error_code1)
>>         )
>>         if(error_code1 != UHD_RX_METADATA_ERROR_CODE_NONE){
>>             fprintf(stderr, "Error code 0x%x was returned during
>> streaming. Aborting: 0x%x.\n", return_code,error_code1);
>>             goto close_file1;
>>         }
>>
>>         // Handle data for stream #0.
>>         fwrite(buff0, sizeof(float) * 2, num_rx_samps0, fp0);
>>         if (verbose) {
>>             time_t full_secs;
>>             double frac_secs;
>>             uhd_rx_metadata_time_spec(md0, &full_secs, &frac_secs);
>>             fprintf(stderr, "Received packet: %zu samples, %.f full secs,
>> %f frac secs\n",
>>                     num_rx_samps0,
>>                     difftime(full_secs, (time_t) 0),
>>                     frac_secs);
>>         }
>>
>>         num_acc_samps0 += num_rx_samps0;
>>
>>         // Handle data for stream #1.
>>         fwrite(buff1, sizeof(float) * 2, num_rx_samps1, fp1);
>>         if (verbose) {
>>             time_t full_secs;
>>             double frac_secs;
>>             uhd_rx_metadata_time_spec(md1, &full_secs, &frac_secs);
>>             fprintf(stderr, "Received packet: %zu samples, %.f full secs,
>> %f frac secs\n",
>>                     num_rx_samps1,
>>                     difftime(full_secs, (time_t) 0),
>>                     frac_secs);
>>         }
>>
>>         num_acc_samps1 += num_rx_samps1;
>>     }
>>     printf("Finished.\n");
>>
>>     // Cleanup
>>     close_file0:
>>         fclose(fp0);
>>
>>     close_file1:
>>         fclose(fp1);
>>
>>     free_buffer0:
>>         if(buff0){
>>             if(verbose){
>>                 fprintf(stderr, "Freeing buffer #0.\n");
>>             }
>>             free(buff0);
>>         }
>>         buff0 = NULL;
>>         buffs_ptr0 = NULL;
>>
>>     free_buffer1:
>>         if(buff1){
>>             if(verbose){
>>                 fprintf(stderr, "Freeing buffer #1.\n");
>>             }
>>             free(buff1);
>>         }
>>         buff1 = NULL;
>>         buffs_ptr1 = NULL;
>>
>>     free_rx_streamer0:
>>         if(verbose){
>>             fprintf(stderr, "Cleaning up RX streamer #0.\n");
>>         }
>>         uhd_rx_streamer_free(&rx_streamer0);
>>
>>     free_rx_streamer1:
>>         if(verbose){
>>             fprintf(stderr, "Cleaning up RX streamer #1.\n");
>>         }
>>         uhd_rx_streamer_free(&rx_streamer1);
>>
>>     free_rx_metadata:
>>         if(verbose){
>>             fprintf(stderr, "Cleaning up RX metadata.\n");
>>         }
>>         uhd_rx_metadata_free(&md0);
>>
>>     free_usrp:
>>         if(verbose){
>>             fprintf(stderr, "Cleaning up USRP.\n");
>>         }
>>         if(return_code != EXIT_SUCCESS && usrp != NULL){
>>             uhd_usrp_last_error(usrp, error_string, 512);
>>             fprintf(stderr, "USRP reported the following error: %s\n",
>> error_string);
>>         }
>>         uhd_usrp_free(&usrp);
>>
>>     free_option_strings:
>>         if(strcmp(device_args,"")){
>>             free(device_args);
>>         }
>>         if(custom_filename0){
>>             free(filename0);
>>         }
>>         if(custom_filename1){
>>             free(filename1);
>>         }
>>
>>     fprintf(stderr, (return_code ? "Failure\n" : "Success\n"));
>>     return return_code;
>> }
>>
>> On Sat, Jul 1, 2017 at 6:36 PM, Michael West <michael.west at ettus.com>
>> wrote:
>>>
>>> Hi Felipe,
>>>
>>> Both the multi_usrp API and the RFNoC API support it.  And yes, you need
>>> to create two different stream objects.
>>>
>>> Regards,
>>> Michael
>>>
>>> On Sat, Jul 1, 2017 at 2:45 AM, Felipe Augusto Pereira de Figueiredo
>>> <zz4fap at gmail.com> wrote:
>>>>
>>>> Dear Michael,
>>>>
>>>> Some more questions follows inline.
>>>>
>>>> Thanks and Kind Regards,
>>>>
>>>> Felipe Augusto
>>>>
>>>> On Sat, Jul 1, 2017 at 2:16 AM, Michael West <michael.west at ettus.com>
>>>> wrote:
>>>>>
>>>>> Hi Felipe,
>>>>>
>>>>> 1)  Yes, that is supported.
>>>>
>>>>
>>>> When you say that is supported, do you mean with legacy UHD API or with
>>>> RFNoC one? Even though I have a x310 I'm still using the legacy API.
>>>>>
>>>>>
>>>>> 2)  There is no example, but it is pretty easy.  Just set the
>>>>> uhd::stream_args_t::channels value correctly for each streamer object.
>>>>
>>>>
>>>> Do I need to create two different stream objects?
>>>>>
>>>>>
>>>>> Regards,
>>>>> Michael
>>>>>
>>>>> On Fri, Jun 30, 2017 at 12:00 PM, Felipe Augusto Pereira de Figueiredo
>>>>> <zz4fap at gmail.com> wrote:
>>>>>>
>>>>>> Dear Michael,
>>>>>>
>>>>>> Thanks for the reply.
>>>>>>
>>>>>> Given your answer, I've got two additional questions:
>>>>>>
>>>>>> 1) Does it mean I can create a RX stream to read RXed samples from the
>>>>>> RF chain 0 (I think you call DSP0) and another RX stream to read samples
>>>>>> from RF chain 1 (DSP1)? I'd like to have a SISO physical layer running
>>>>>> (TX/RX) on the RF chain 0 at frequency X and sample rate Y and a spectrum
>>>>>> sensing module with different sampling rate Z at frequency W on the RF chain
>>>>>> 1.
>>>>>>
>>>>>> 2) Is there any example on how to create different streamers to
>>>>>> receive/transmit using different RF Chains?
>>>>>>
>>>>>> Many Thanks and Kind Regards,
>>>>>>
>>>>>> Felipe Augusto
>>>>>>
>>>>>> On Fri, Jun 30, 2017 at 8:32 PM, Michael West <michael.west at ettus.com>
>>>>>> wrote:
>>>>>>>
>>>>>>> Hi Felipe,
>>>>>>>
>>>>>>> Yes.  If you create different streamers, each with a different set of
>>>>>>> channels, each streamer can be configured independently.
>>>>>>>
>>>>>>> Regards,
>>>>>>> Michael
>>>>>>>
>>>>>>> On Tue, Jun 27, 2017 at 7:28 AM, Felipe Augusto Pereira de Figueiredo
>>>>>>> via USRP-users <usrp-users at lists.ettus.com> wrote:
>>>>>>>>
>>>>>>>> Dear folks,
>>>>>>>>
>>>>>>>> I've got a x310 and I'd like to know if it is possible to open two
>>>>>>>> streams with different streaming modes at the same time in the same USRP
>>>>>>>> hardware.
>>>>>>>>
>>>>>>>> For example, the first RF chain would be configures as
>>>>>>>>
>>>>>>>> UHD_STREAM_MODE_START_CONTINUOUS
>>>>>>>>
>>>>>>>> and the second one would be set to
>>>>>>>>
>>>>>>>> UHD_STREAM_MODE_NUM_SAMPS_AND_DONE
>>>>>>>>
>>>>>>>> Is is possible?
>>>>>>>>
>>>>>>>> Thanks and Kind regards,
>>>>>>>>
>>>>>>>> Felipe Augusto
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> USRP-users mailing list
>>>>>>>> USRP-users at lists.ettus.com
>>>>>>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>




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