EP4CE30F29C7N Datasheet, PDF (390/488 Pages) Altera Corporation – Cyclone IV Device Handbook, Volume 1

2–16
Chapter 2: Cyclone IV Reset Control and Power Down
Transceiver Reset Sequences
This solution may violate some of the protocol specific requirements. In such case,
you can use Manual CDR lock option.
■ For Manual CDR lock mode, rx_freqlocked signal is not available. Upon
detection of a dead link, take the following steps:
a. Switch to LTR mode.
b. Assert rx_digitalreset.
c. Wait for rx_pll_locked to go high.
d. When you detect incoming data on the receive pins, switch to LTD mode.
e. Wait for a duration of t_{LTD_Manual}, which is the time taken to recover valid data
after the rx_locktodata signal is asserted in manual mode.
f. De-assert rx_digitalreset.
Cyclone IV Device Handbook,
Volume 2
May 2013 Altera Corporation