3–72
Altera Corporation
Stratix II GX Device Handbook, Volume 2
October 2007
Channel and PMA Controls Reconfiguration
Channel Reconfiguration Design Examples
This section provides three examples for performing dynamic
reconfiguration on a transceiver channel.
Example 1—Configuring a Transceiver Channel Between GIGE Mode and
SONET/SDH OC48 Mode
The GIGE mode in the ALT2GXB megafunction is different from the
SONET/SDH OC48 mode in data path, clocking, and PLD interface
width. The differences between the two modes are listed in
Table 3–5
.
These differences determine the selection of parameters in the ALT2GXB
MegaWizard and the required PLD logic to configure a transceiver
channel between these two modes.
Figure 3–35
shows the required
functional blocks to perform channel reconfiguration.
Table 3–5. Differences Between GIGE and SONET/SDH OC48
Number
Functional Block
GIGE
SONET/SDH
OC48
1
PLD width
8
16
2
8B/10B enabled
Yes
No
3
Rate matcher
Yes
No
4
Byte order block
No
Yes
5
Clock used for
synchronizing the
receive output
data
(
rx_dataout
)
tx_clkout
(since rate
matcher is used)
rx_clkout
6
Data rate
1.25 Gbps
2.488 Gbps
7
Allowed input
reference clock
62.5 MHz
125 MHz
77.76 MHz
155.52 MHz
311.04 MHz
622.08 MHz
8
PCS-PMA
interface width
10
(since data is
8B/10B encoded)
8