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Error detection and management, Physical layer error management, Error detection and management –61 – Altera RapidIO MegaCore Function User Manual

Page 107: Physical layer error management –61

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Chapter 4: Functional Description

4–61

Error Detection and Management

August 2014

Altera Corporation

RapidIO MegaCore Function

User Guide

Error Detection and Management

The error detection and management mechanisms in the RapidIO specification and
those built into the RapidIO IP core provide a high degree of reliability. In addition to
error detection, management, and recovery features, the RapidIO IP core also
provides debugging and diagnostic aids.

This section describes the error detection and management features in the RapidIO IP
core.

Physical Layer Error Management

Errors at the Physical layer are mainly of the following two types:

Protocol violations

Transmission errors

Protocol violations can be caused by a link partner that is not fully compliant to the
specification, or can be a side effect of the link partner being reset.

Transmission errors can be caused by noise on the line and consist of one or more bit
errors. The following mechanisms exist for checking and detecting errors:

The receiver checks the validity of the received 8B10B encoded characters,
including the running disparity.

The receiver detects control characters changed into data characters or data
characters changed into control characters, based on the context in which the
character is received.

The receiver checks the CRC of the received control symbols and packets.

4

Payload

Byte16,17

[63:48]

16'h1112

Payload double word 2

Payload

Byte18,19

[47:32]

16'h1314

Payload

Byte20,21

[31:16]

16'h1516

Payload

Byte22,23

[15:0]

16'h1718

5

Payload

Byte24,25

[63:48]

16'h191a

Payload double word 3

Payload

Byte26,27

[47:32]

16'h1b1c

Payload

Byte28,29

[31:16]

16'h1d1e

Payload

Byte30,31

[15:0]

16'h1f20

Table 4–16. RapidIO Header Fields on the gen_tx_data Bus (Part 2 of 2)

Cycle

Field

gen_tx_data bus

Value

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