HC4GX15 Datasheet, PDF (542/668 Pages) Altera Corporation – HardCopy IV Device Handbook

2–84
Chapter 2: HardCopy IV GX Dynamic Reconfiguration
Description of Transceiver Channel Reconfiguration Modes
Table 2–27. Receiver Core Clocking (Part 2 of 2)
■ Enable this option if you want
tx_clkout of the first
channel (channel 0) of the
transceiver block to provide
the read clock to the Receive
Phase Compensation FIFOs of
the remaining receiver
channels in the transceiver
block.
■ This option is typically enabled
when all the channels of a
transceiver block are in a Basic
or Protocol configuration with
Rate Matching enabled and are
reconfigured to another Basic
or Protocol configuration with
Rate Matching enabled.
■ Consider the following
scenario:
Four regular transceiver
channels configured to
Basic 2 Gbps functional
mode with Rate Matching
enabled.
Channel and CMU PLL
Reconfiguration mode is
enabled in the
ALTGX_RECONFIG
MegaWizard Plug-In
Manager.
You want to reconfigure all
four regular transceiver
channels to 3.125 Gbps
configuration with Rate
Matching enabled.
■ Option 1 is applicable in this
scenario.
■ Figure 2–42 shows the sharing
of channel 0’s tx_clkout
between all four channels of a
transceiver block.
■ Enable this option if you want the
individual transmitter channel’s
tx_clkout signal to provide the read
clock to its respective Receive Phase
Compensation FIFO.
■ This option is typically enabled when all
the transceiver channels have Rate
Matching enabled with different data
rates and are reconfigured to another
Basic or Protocol functional mode with
Rate Matching enabled.
■ Consider the following scenario:
TX1/RX1: You want to dynamically
reconfigure Basic 1 Gbps
configuration with Rate Matching
enabled to Basic 2 Gbps
configuration with Rate Matching
enabled.
TX3/RX3: You want to dynamically
reconfigure Basic 4 Gbps
configuration with Rate Matching
enabled to Basic 1 Gbps
configuration with Rate Matching
enabled.
TX0/RX0: You want to dynamically
reconfigure Basic 3.125 Gbps
configuration with Rate Matching
enabled to 1 Gbps configuration with
Rate Matching and vice versa.
Channel and CMU PLL
Reconfiguration mode is enabled in
the ALTGX_RECONFIG MegaWizard
Plug-In Manager.
■ Option 2 is applicable in this scenario
because the design requires the
individual transceiver channels to be
reconfigured with different data rates to
another Basic or Protocol functional
mode with Rate Matching. Therefore,
each channel can be reconfigured to
another Basic or Protocol functional
mode with Rate Matching enabled and a
different data rate.
■ Enable this option if you want the
individual channel’s rx_clkout
signal to provide the read clock to its
respective Receive Phase
Compensation FIFO.
■ This option is typically enabled when
the channel is reconfigured from a
Basic or Protocol configuration with or
without Rate Matching to another Basic
or Protocol configuration with or
without Rate Matching.
■ Consider the following scenario:
TX1/RX1: GIGE configuration to
SONET/SDH OC48 configuration.
TX2/RX2: Basic 2.5 Gbps
configuration with Rate Matching
disabled to Basic 1.244 Gbps
configuration with Rate Matching
disabled.
Channel and CMU PLL
Reconfiguration mode is enabled in
the ALTGX_RECONFIG MegaWizard
Plug-In Manager
■ Option 3 is applicable in this scenario.
■ Figure 2–44 shows the respective
rx_clkout of each channel, clocking
the respective receiver channels of a
transceiver block.
■ Figure 2–43 shows the respective
tx_clkout of each channel clocking
the respective channels of a transceiver
block.
Note to Table 2–27:
(1) The Reconfig 2 screen is not available for PMA-only channels (channels configured in Basic [PMA Direct] ×1 and ×N modes).
HardCopy IV Device Handbook, Volume 3
© June 2009 Altera Corporation