Altera DisplayPort MegaCore Function User Manual
Page 56
downstream Reed-Solomon decoder. The format differs for both header and payload, as shown in the
following figure.
Figure 5-8: rxN_ss Input Data Format
0
nb0
nb1
nb2
nb3
0
0
0
0
nb4
nb5
nb6
nb7
p0
p1
0
0
0
0
0
0
0
0
0
0
0
nb0
nb1
p0
p1
15-Nibble Code Word
for Packet Payload
15-Nibble Code Word
for Packet Header
The following figure shows a typical secondary stream packet with the four byte header (HB0, HB1, HB2,
and HB3) and 32-byte payload (DB0, ..., DB31). Each symbol has an associated parity nibble (PB0, ...,
PB11). Downstream logic can use the start-of-packet and end-of-packet to determine if the current input
is a header or payload symbol.
Data is clocked out of the
rxN_ss
port using the
rx_ss_clk
signal. This signal is the same phase and
frequency as the main link lane 0 clock.
5-20
Secondary Stream Interface
UG-01131
2015.05.04
Altera Corporation
DisplayPort Sink