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Altera_Forum
Honored Contributor
15 years agoByte enables are part of the TLP, there is a »first DW BE« and a »last DW BE« field in the header. Look at a Section called » First/Last DW Byte Enables Rules« in your PCI Express Specification.
rx_st_be0 is an optional convenience signal introduced by Altera for received packets only, you could equally decode and use first/last DW Byte Enables of the received TLP. Upon transmission you can only set byte enables based on the mentioned TLP fields.