Visible to Intel only — GUID: nik1409855270695
Ixiasoft
Visible to Intel only — GUID: nik1409855270695
Ixiasoft
1.3.2.1. Word Aligner
Parallel data at the input of the receiver PCS loses the word boundary of the upstream transmitter from the serial-to-parallel conversion in the deserializer. The word aligner receives parallel data from the deserializer and restores the word boundary based on a pre-defined alignment pattern that must be received during link synchronization.
The word aligner searches for a pre-defined alignment pattern in the deserialized data to identify the correct boundary and restores the word boundary during link synchronization. The alignment pattern is pre-defined for standard serial protocols according to the respective protocol specifications for achieving synchronization. For proprietary protocol implementations, you can specify a custom word alignment pattern specific to your application.
In addition to restoring the word boundary, the word aligner implements the following features:
- Synchronization state machine
- Programmable run length violation detection (for all transceiver configurations)
- Receiver polarity inversion (for all transceiver configurations except PCIe)
- Receiver bit reversal (for custom single- and double-width configurations only)
- Receiver byte reversal (for custom double-width configuration only)
The word aligner operates in one of the following three modes:
- Manual alignment
- Automatic synchronization state machine
- Bit-slip
- Deterministic latency state machine
Except for bit-slip mode, after completing word alignment, the deserialized data is synchronized to have the word alignment pattern at the LSB portion of the aligned data.
When the 8B/10B encoder/decoder is enabled, the word aligner detects both positive and negative disparities of the alignment pattern. For example, if you specify a /K28.5/ (b’0011111010) pattern as the comma, rx_patterndetect is asserted if b’0011111010 or b’1100000101 is detected in the incoming data.
Section Content
Word Aligner Options and Behaviors
Word Aligner in Manual Alignment Mode
Word Aligner in Bit-Slip Mode
Word Aligner in Automatic Synchronization State Machine Mode
Word Aligner in Automatic Synchronization State Machine Mode with a 10-Bit PMA-PCS Interface Configuration
Word Aligner Operations in Deterministic Latency State Machine Mode
Programmable Run-Length Violation Detection
Receiver Polarity Inversion
Bit Reversal
Receiver Byte Reversal