diff options
| -rw-r--r-- | host/docs/usrp_n3xx.dox | 67 |
1 files changed, 58 insertions, 9 deletions
diff --git a/host/docs/usrp_n3xx.dox b/host/docs/usrp_n3xx.dox index bea250071..ca8ae49bd 100644 --- a/host/docs/usrp_n3xx.dox +++ b/host/docs/usrp_n3xx.dox @@ -264,7 +264,9 @@ that will request a network address from your DHCP server (if available on your network). The SFP+ (sfp0, sfp1) ports are configured with static addresses 192.168.10.2/24 -and 192.168.20.2/24 respectively. +and 192.168.20.2/24, respectively. Their default MTU value is 8000. These +settings are independent of the image type (HG vs. XG), i.e., the defaults are +the same for 1 GigE and 10 GigE (unlike the X310!). The configuration for the sfpX port is stored in /etc/systemd/networkd/sfpX.network. @@ -293,7 +295,7 @@ The factory settings are as follows: Address=192.168.10.2/24 [Link] - MTUBytes=9000 + MTUBytes=8000 sfp1 (static): @@ -304,14 +306,20 @@ The factory settings are as follows: Address=192.168.20.2/24 [Link] - MTUBytes=9000 + MTUBytes=8000 -Note: Care needs to be taken when editing these files on the device, since -vi / vim sometimes generates undo files (e.g. /etc/systemd/networkd/sfp0.network~), -that systemd-networkd might accidentally pick up. -Note: Temporarily setting the IP addresses via ifconfig etc will only change the -value until the next reboot or reload of the FPGA image. +Additional notes on networking: + +- Care needs to be taken when editing these files on the device, since + vi / vim sometimes generates undo files (e.g. + `/etc/systemd/networkd/sfp0.network~`), that systemd-networkd might + accidentally pick up. +- Temporarily setting the IP addresses or MTU sizes via `ifconfig` or other + command line tools will only change the value until the next reboot or reload + of the FPGA image. +- If the MTU of the device and host computers differ, streaming issues can + occur. \subsection n3xx_getting_started_security Security-related settings @@ -419,6 +427,28 @@ See also uhd::usrp::subdev_spec_t. \subsection n3xx_usage_sensors The sensor API +Like other USRPs, the N3x0 series have daughterboard and motherboard sensors. +When using uhd::usrp::multi_usrp, the following API calls are relevant to +interact with the sensor API: + +- uhd::usrp::multi_usrp::get_mboard_sensor_names() +- uhd::usrp::multi_usrp::get_mboard_sensor() +- uhd::usrp::multi_usrp::get_tx_sensor_names() +- uhd::usrp::multi_usrp::get_rx_sensor_names() +- uhd::usrp::multi_usrp::get_tx_sensor() +- uhd::usrp::multi_usrp::get_rx_sensor() + +The following motherboard sensors are always available: + +- `ref_locked`: This will check that all the daughterboards have locked to the + external reference. +- `temperature`: The temperature of the die itself +- `gps_lock`: GPS lock +- `gps_time`: GPS time in seconds sin ce the epch +- `gps_tpv`: A TPV report from GPSd serialized as JSON +- `gps_sky`: A SKY report from GPSd serialized as JSON + + \section n3xx_rasm Remote Management \subsection n3xx_rasm_mender Mender: Remote update capability @@ -532,7 +562,7 @@ FPGA must be loaded. SFP0 will not be available for data transport in this mode. The White Rabbit image is provided as a default image. To obtain the default images, simply run: - $ uhd_images_downloader + $ uhd_images_downloader -t n3xx -t fpga Then, you can install the WX (or WA) image using `uhd_image_loader`: @@ -547,6 +577,25 @@ auto usrp = uhd::usrp::multi_usrp::make("type=n3xx,clock_source=sfp0,time_source For more information, refer to the [White Rabbit Homepage](https://www.ohwr.org/projects/white-rabbit), or the [Ettus Research Knowledge Base](https://kb.ettus.com/Using_Ethernet-Based_Synchronization_on_the_USRP%E2%84%A2_N3xx_Devices). +\section n3xx_troubleshooting Troubleshooting + +\subsection n3xx_troubleshooting_seqerrs Errors while streaming + +If you are getting sequence or other errors while streaming, make sure the MTU +settings of the network devices match up. UHD will try and do an automatic MTU +discovery, but there are cases when the automatic MTU discovery will yield +incorrect values. Often, the host computer MTU is set smaller than the device +MTU, but the MTU discovery will detect a larger MTU than the host computer MTU +in this error case. + +The default MTU for the N3x0 series is 8000. The simplest solution is often to +set the host computer MTU to 8000 as well: + + $ [sudo] ifconfig eth0 mtu 8000 # Replace eth0 with the device you're using + +Of course, you can also reduce the MTU on the device to match your host +computer, see Section \ref n3xx_getting_started_connectivity. + \section n3xx_theory_of_ops Theory of Operation The N3xx-series are devices based on the MPM architecture (see |