Altera Avalon ST "emptyWithinPacket"

[shaiko]

Altera Avalon Spec:
https://www.altera.com/en_US/pdfs/literature/manual/mnl_avalon_spec.pdf
Page 41.

emptyWithinPacket - When true, empty is valid for the entire packet.

When this parameter is false then an "empty" symbol can appear only at the end of frame.
When this parameter is true then an "empty" symbol can appear anywhere in the packet.

Is my interpretation correct ?

 

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From what I can tell the FALSE value means that the empty signal defines how many symbols have no data when endofpacket is asserted.

A TRUE value means that the empty signal is always looked at for every beat of the packet so you could perhaps have it set to 2 and only use the upper half of a 32-bit bus. It also brings up the question if whether or not the master can change the empty signal value mid packet and I'd assume that the slave has to respond accordingly.