Altera POS-PHY Level 4 IP Core User Manual

Page 93

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Chapter 5: Functional Description—Transmitter

5–23

Signals

December 2014

Altera Corporation

POS-PHY Level 4 IP Core User Guide

ctl_td_alpha[7:0]

Input

tdint_clk

Number of training pattern sequence repetitions. This
value only applies to interval training patterns. If a
training pattern is inserted due to stat_ts_sync
deasserted, the training pattern lasts until
stat_ts_sync

is asserted, and the current 20-cycle

training pattern completes. Setting to zero results in
an ALPHA of 256. Only change at reset.

ctl_td_burstlen[9:0]

Input

For the individual buffers mode, this input sets the
legal burst unit size, formerly known as burst
length. A burst must end on either a non-zero
multiple of ctl_td_burstlen, or on an EOP.

For the shared buffer with embedded addressing
mode, this input only limits when the IP core may
read data from the buffer. This input enables
delineating bursts, as in the individual buffers
case, only if the user logic pushes bursts into the
buffer with the desired delineation.

In either mode, this input also delays insertion of
training patterns after MaxT so that bursts are not
interrupted.

Units are in bytes. Supports M to 1,024 bytes in
increments of M, where M equals 16 or 32 bytes
depending on the Atlantic buffer width.

ctl_td_burstlimit[10:0]

Input

Sets the maximum burst size to be sent by the
transmitter. A control word is inserted at the end of
the burst limit. Burst limit values are restricted to
multiples of burst unit size (set via
ctl_td_burstlen[9:0]

), and depending on other

transmitter parameters, the values may be limited to
a minimum value. You can use IP Toolbench to
determine the valid values (set Parameter Type to
Fixed Value to determine the valid values, and then
set back to Real Time Programmable). The units are
in bytes.

Table 5–8. Data Path and Control Status (Part 2 of 2)

Signal

Direction

Clock Domain

Description

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