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Altera_Forum
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14 years ago

BeMicro SDK - Nios II/f - Cyclone IV - Performance - dhrystone

Hi All, We are using the - BeMicro SDK board - (no link provided as need more than five posts) I'm trying to measure the dhrystone performance of this set up. (i.e. to determine if this...
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Altera_Forum
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14 years ago

If you are doing a lot of TCP/IP then the checksum routine needs some TLC.

The nios cpu doesn't have a 32bit 'add with carry' instruction so the checksum loop is horrid, a custom instruction to add the two 16bit halves of one word onto another helps no end. The byteswap one will help elsewhere (if you can persuade the compiler to use it properly).

But I'm not at all sure any 100MHz cpu can 80% load a 100M ethernet with non-trivial traffic.