regarding COE mailbox sending and receiving issues

OpenEtherCATsociety / SOEM

Simple Open Source EtherCAT Master

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regarding COE mailbox sending and receiving issues #778

Closed fyyxxm closed 9 months ago

fyyxxm commented 9 months ago

If I send a message through COE mailbox (ecx-TxPDO()), what should be the value of the input parameter TxPDOnumber for this function? Is it index or something else?

ArthurKetels commented 9 months ago

As far as I know there are no slaves that support PDO over CoE. I never had the opportunity to test these functions. It is in the EtherCAT standard however, that is why it is implemented in SOEM.

All PDO transfers are via virtual memory by means of FMMU. And the support for this lays in ecx_send_processdata, ecx_receive_processdata and friends. Or ,if you want to do it yourself, in low level instructions LRD, LWR and LRW.

fyyxxm commented 9 months ago

Understood, thank you for your explanation