Thank you for a reply.
Is it necessary? Can we change a buffer size by changing PD_INPUT_SIZE and PD_OUTPUT_SIZE defs? Here I changed it from 4 to 32 (8 int’s), and it seems, that memory was allocated properly.
Then, I changed TIEtherCATLib.xml to increase Tx/RxPDO size. It seems, buffer size was changed too. A connection runs well, without errors and a red led blinking, but I can change only the first 4 bytes (I named it LED 1), as in demo example, the rest stays unmodified.
I suppose, maybe there is no necessity in SSC for a such change, because it seems, that a mechanism of changing buffer size was provided in the demo example. Otherwise, for what a function Ecat_Open has arguments, that could be changed? Could you comment that, please?