Cyclone V Device Handbook: Volume 2: Transceivers

ID 683586
Date 10/24/2018
Document Table of Contents Byte Ordering

When you enable the byte deserializer, the output byte order may not match the originally transmitted ordering. For applications that require a specific pattern to be ordered at the LSByte position of the data, byte ordering restores the proper byte order of the byte-deserialized data before forwarding it to the FPGA fabric.

Byte ordering operates by inserting a predefined pad pattern to the byte-deserialized data if the predefined byte ordering pattern found is not in the LSByte position.

Byte ordering requires the following:

  • A receiver with the byte deserializer enabled
  • A predefined byte ordering pattern that must be ordered at the LSByte position of the data
  • A predefined pad pattern

Byte ordering supports operation in single- and double-width modes. Both modes support operation in word aligner-based and manual ordering modes.