From c6042a0b317a6f74d2b74b259f14431f5c8246d4 Mon Sep 17 00:00:00 2001 From: Josh Blum Date: Wed, 13 Oct 2010 14:28:52 -0700 Subject: usrp2: added docs on flow control ricer args and using usrp2 with a switch implemented flow control param hints in the mboard impl --- host/docs/transport.rst | 11 +++++++++++ host/docs/usrp2.rst | 15 +++++++-------- 2 files changed, 18 insertions(+), 8 deletions(-) (limited to 'host/docs') diff --git a/host/docs/transport.rst b/host/docs/transport.rst index 432db4bb5..2f730f8e4 100644 --- a/host/docs/transport.rst +++ b/host/docs/transport.rst @@ -39,6 +39,17 @@ The following parameters can be used to alter the transport's default behavior: **Note:** num_send_frames and concurrency_hint will not have an effect as the asynchronous send implementation is currently disabled. +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +Flow control parameters +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +The host-based flow control expects periodic update packets from the device. +These update packets inform the host of the last packet consumed by the device, +which allows the host to determine throttling conditions for the transmission of packets. +The following mechanisms affect the transmission of periodic update packets: + +* **ups_per_fifo:** The number of update packets for each FIFO's worth of bytes sent into the device +* **ups_per_sec:** The number of update packets per second + ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Resize socket buffers ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/host/docs/usrp2.rst b/host/docs/usrp2.rst index 1ebab388a..8fa666a49 100644 --- a/host/docs/usrp2.rst +++ b/host/docs/usrp2.rst @@ -39,12 +39,10 @@ Use the card burner tool (windows) ------------------------------------------------------------------------ Setup networking ------------------------------------------------------------------------ -The USRP2 only supports gigabit ethernet, and -will not work with a 10/100 Mbps interface. -Because the USRP2 uses gigabit ethernet pause frames for flow control, -you cannot use multiple USRP2s with a switch or a hub. -It is recommended that each USRP2 be plugged directly into its own -dedicated gigabit ethernet interface on the host computer. +The USRP2 only supports gigabit ethernet, +and will not work with a 10/100 Mbps interface. +However, a 10/100 Mbps interface can be connected indirectly +to a USRP2 through a gigabit ethernet switch. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Setup the host interface @@ -63,8 +61,9 @@ It is recommended that you change or disable your firewall settings. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Multiple device configuration ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -As described above, you will need one ethernet interface per USRP2. -Each ethernet interface should have its own subnet, +For maximum throughput, one ethernet interface per USRP2 is recommended, +although multiple devices may be connected via a gigabit ethernet switch. +In any case, each ethernet interface should have its own subnet, and the corresponding USRP2 device should be assigned an address in that subnet. Example: -- cgit v1.2.3