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Altera_Forum
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13 years ago

Ethernet roundtrip time with NicheStack & Nios-II

Hi, We are using TSE IP with NichStack, MicroC OS-II on Nios-II. FPGA is running a simple UDP host which echoes all packets it gets from client. The client is a PC running real-time OS and con...
Altera_Forum's avatar
Altera_Forum
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13 years ago

Thanks Cris72 and Daixiwen.

The UDP setup: PC with a RTOS is a very simple UDP client which sends UDP packets. 128 bytes payload. Nios-II app is a modified UDP server based on "Simple Socket Server" TCP template. Current round-trip time as measured on the PC client side (using RTOS APIs) is about 30-40 ms. Board is "Cyclone IV GX Transceiver Started Kit" with original SOPC.

SOPC screenshot is attached. One of the tutorials mentioned using "sdram" for "linker section names". I noticed that the board does not have "sdram"; it has "onchip_ram" and "ssram", to which the CPU intr/data masters are connected. Could it be the mem speed issue due to this arrangement?

Will set -O2 optimization. Will also increase CPU clk and look into CPU profiling.

Any idea how to check if the TSE IP driver is interrupt-driven or is polling?

We are trying to get round-trip time in sub-millisecond range.

-swguy