Altera POS-PHY Level 4 IP Core - Manual (Page 26)

3–6 Chapter 3: Parameter Settings
Optional Features
POS-PHY Level 4 IP Core User Guide December 2014 Altera Corporation
Optional Features
Figure 3–2 on page 3–6 shows the Optional Features tab.
These parameters allow you to enable additional features that the IP core provides.
Each parameter may increase or decrease the number of logic resources.
Turn on Atlantic error checking to add a packet filtering module to the write side of
every Atlantic FIFO buffer. The packet filtering module ensures that only properly
formatted packets are passed through the Atlantic FIFO buffer. When you turn off
Atlantic error checking
, the packet filtering module is not added.
The packet filtering module corrects start-of-packet (SOP) and end-of-packet (EOP)
errors before writing packets into the FIFO buffer. For a missing SOP (where data or
an EOP is received for a port without first having received a SOP), an error output is
asserted, and data is not written to the buffer until a SOP is received. For a missing
EOP (where a SOP is received before the previous packet’s EOP), the current packet is
terminated by an EOP, and ERR is asserted. The next packet is stored normally.
For individual buffers variations with a large number of ports, the Atlantic error
checking
increases the amount of logic.
Atlantic error checking is often desirable for receivers, but less applicable for
transmitters because the incoming user-Atlantic data may be presumed correct.
Figure 3–2. Receiver Optional Features