EtherCAT Latency on ARM335x

Hithesh

How would you test the time delay from the ECAT Master issuing an ON command and the Slave actually turning the output ON.

By output I mean a digital output going from 0 to 24V.

Can I use an oscilloscope to look at the ECAT Master(ARM335x) Frame at the RJ45 connector?

This can probably be measured using software time stamping etc. But I would like to measure it using hardware.

0 Biser Gatchev-XID over 12 years ago

I'm not an expert but maybe you should toggle a GPIO at the end of the ON command and measure delay between the two fronts.

0 Hithesh over 12 years ago in reply to Biser Gatchev-XID

Genius 3290 points

Biser Gatchev-XID said:

I'm not an expert but maybe you should toggle a GPIO at the end of the ON command and measure delay between the two fronts.

This is exacty what I meant.

Let's say you have a Slave IO device. All the outputs are at 0V.

At T=0, the ECAT Master sends a command to turn on one of the outputs.

At T=(x)usecs, the slave output goes to 24V.

The latency is x microsecs.

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