Altera 100G Interlaken MegaCore Function User Manual
Page 62
100G Interlaken IP Core User Data Transfer Interface Signals
Table 5-4: 100G Interlaken IP Core User Data Transfer Interface
Signal Name
Direction Width
(Bits)
Description
100G Interlaken IP Core Transmit User Interface
itx_chan
Input
8
Transmit logic channel number. The IP core supports up to 256
channels. The 100G Interlaken IP core samples this value only when a
bit of
itx_sop
or
itx_sob
is high and
itx_num_valid
has a non-zero
value.
itx_num_
valid
Input
8
itx_num_valid[7:4]
specifies the number of valid 64-bit words in the
current packet in the current data symbol. The maximum value of
itx_num_valid[7:4]
is eight, because a data symbol on the 512 bit
wide data path has eight words (8 x 64 bits = 512 bits).
In non-valid cycles, you must set the value of
itx_num_valid[7:4]
to
zero.
In valid cycles, you must set the value of
itx_num_valid[7:4]
as
follows:
• 4’b1000: if all eight words contain valid data from the current
packet.
• 4’b0xxx: where xxx indicates the number of valid words that are
part of the current packet, if the number is less than eight. Data is
always MSB aligned (left aligned). For example, the value of 4’b0111
indicates that word 0 (bit [63:0]) is not valid.
In dual segment mode, if the value of
itx_num_valid[7:4]
is four or
less (but not zero), the application can hold
itx_num_valid[2]
high to
indicate the current data symbol also includes the first four 64-bit
words of a new packet. The only valid values for
itx_num_valid[3:0]
are 4'b0100 and 4'b0000.
When
itx_num_valid[3:0]
has the value of 4'b0100, you must also
hold
itx_sop[0]
high.
You must set the value of
itx_num_valid
to zero in all non-valid
cycles, even when
itx_ready
is not asserted.
itx_sop
Input
2
Indicates the current data symbol on
itx_din_words
contains the start
of a packet (SOP). This signal has the following valid values:
• 2'b00—The current data symbol does not contain the start of a
packet.
• 2'b10— If
itx_sop[1]
has the value of 1, the start-of-packet aligns
with the most significant byte (byte 63) of the data.
• 2'b01— If
itx_sop[0]
has the value of 1, the start-of-packet aligns
with byte 31 of the data.
5-4
100G Interlaken IP Core User Data Transfer Interface Signals
UG-01128
2015.05.04
Altera Corporation
100G Interlaken MegaCore Function Signals