HC4GX15 Datasheet, PDF (344/668 Pages) Altera Corporation – HardCopy IV Device Handbook

1–80
Chapter 1: HardCopy IV GX Transceiver Architecture
Receiver Channel Datapath
1 If the word alignment pattern is known to be unique and does not appear between
word boundaries, you can constantly hold the rx_enapatternalign signal high
because there is no possibility of false word alignment. If there is a possibility of the
word alignment pattern occurring across word boundaries, you must control the
rx_enapatternalign signal to lock the word boundary after the desired word
alignment is achieved to avoid re-alignment to an incorrect word boundary.
Bit-Slip Mode Word Aligner with 10-Bit PMA-PCS Interface Mode
In some Basic single-width configurations with a 10-bit PMA-PCS interface, you can
configure the word aligner in bit-slip mode by selecting the Use manual bit slipping
mode option in the ALTGX MegaWizard Plug-In Manager.
The word aligner operation for Basic single-width with a 10-bit PMA-PCS interface is
similar to the word aligner operation in Basic single-width mode with 8-bit PMA-PCS
interface. For word aligner operation in bit-slip mode, refer to “Manual Alignment
Mode Word Aligner with 8-Bit PMA-PCS Interface Modes” on page 1–75. The only
difference is that the bit-slip word aligner with 10-bit PMA-PCS interface modes allow
7-bit and 10-bit word alignment patterns, whereas 8-bit PMA-PCS interface modes
allow only 16-bit word alignment patterns.
Word Aligner in Double-Width Mode
In double-width mode, the PMA-PCS interface is either 16 bit or 20 bit wide. In 16-bit
PMA-PCS interface modes, the word aligner receives 16-bit wide data from the
deserializer. In 20-bit PMA-PCS interface modes, the word aligner receives 10 bit wide
data from the deserializer. Depending on the configured functional mode, you can
configure the word aligner in manual alignment mode or bit-slip mode. The
automatic synchronization state machine mode is not supported for word aligner in
double-width mode.
Word Aligner in Double-Width Mode with 16-Bit PMA-PCS Interface Modes
The following functional modes support the 16-bit PMA-PCS interface:
■ SONET/SDH OC-96
■ (OIF) CEI PHY interface
■ Basic double-width
Table 1–22 shows the word aligner configurations allowed in functional modes with
16-bit PMA-PCS interface.
Table 1–22. Word Aligner Configurations with a 16-Bit Wide PMA-PCS Interface (Note 1)
Functional Mode
Allowed Word Aligner
Configurations
Allowed Word Alignment
Pattern Length
SONET/SDH OC-96
Manual Alignment
Basic double-width
Manual Alignment, Bit-Slip
Note to Table 1–22:
(1) The word aligner is bypassed in (OIF) CEI PHY interface mode.
16 bits, 32 bits
8 bits, 16 bits, 32 bits
HardCopy IV Device Handbook Volume 3
© June 2009 Altera Corporation