[RTnet-users] tdmacfg: calibrated master-to-slave packet delay

[Klemen D. <kle...@ya...>]

Hello everybody,

I am testing the rtnet tdma master/slave configuration on two machines with 100 Mb ethernet card. I ran the TDMA calibration and the dmesg showed the result: "[ 3878.693492] TDMA: calibrated master-to-slave packet delay: 3 us (min/max: 2/4 us)". I am not sure how is it possible that the number is that small. The smallest possible ethernet frame, 64B in length, transmitted at 100 Mb/s would need at least 64*8/100E9 = 5,12 us to travel from master to slave. Does anybody know why do i get such a result?

Regards
Klemen