[etherlab-users] Estimation of master Tx rate

[Pierre Letier]

Hello,

Can somebody explain me how I can estimate the Master Tx Rate based on 
the list of exchanged PDO's with the slaves (an all other related 
things). I tried to compute it based on the structure of an Ethernet 
frame but I never found the good value. I don't found a consistent rule 
that fit different examples. For instance, I have two programs with the 
first exchanging 26 Bytes of PDOS and the second 40 Bytes. Both are 
running at 1kHz (communication rate with the slave). With the first I 
have a Tx rate of 60.5 kByte/s and for the second 69.8 kBytes. Thus a 
difference around 9.3 kBytes/s although I have, in practice, 14 kBytes/s 
more to exchange (14 x 1000). I though first to the 1024 conversion for 
the Byte, but the difference is bigger.

As anybody more information about that ?

Thank you

Pierre Letier

-- 
Pierre Letier
Robotics Engineer

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1987 - 2012

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