Black Channel: General Black Channel type 2 - Simplex/Broadcast

Black Channel: General Black Channel type 2 - Simplex/Broadcast BLCH0003
status: PASS
tags: blch
date: 2025-08-06

Overview

The GBC2 (General Black Channel type 2) implements a simplex/broadcast protocol from one transmitting simplifier to one or many receiving simplifier. See GBC2 Specification for implementation details.

61508-2:2010 7.4.11.1 requirements

error type

mitigation

PASS

Reference

transmission errors

Protected by 32-bit CRC

TRUE

See HIL100 CI job

repetitions

protected by timestamp

TRUE

See HIL100 CI job

deletion

As there is no state in the data, just update, deletion is not critical

TRUE

N/A

insertion

protected by timestamp

TRUE

See HIL100 CI job

re-sequencing

protected by timestamp

TRUE

See HIL100 CI job

corruption

Protected by CRC and secure hash

TRUE

See HIL100 CI job

delay

protected by timestamp

TRUE

See HIL100 CI job

masquerade

unique serial numbers is used to verify correctness

TRUE

See HIL100 CI job

61784-3:2021 Annex D - Verification of safety measures

Verification

mitigation

Pass

Reference

D.4.3 ”De-Energize to trip”

A communication timeout is implemented in the receiving end

TRUE

See CI job for HIL100

D.4.4 ”Safe state”

Loss of packets sets all signals to ”OFF”, which is safe state for them

TRUE

See CI job for HIL100

D.4.5 ”Transmission errors”

CRC mismatch is handled as lost packet

TRUE

See CI job for HIL100

D.4.6 ”Safey reaction and response times”

The communication timeout is configured according to the application requirements

TRUE

See CI job for HIL100

61784-3:2021 5.4 - Deterministic remedial measures

error type

mitigation

PASS

Reference

5.4.2 Sequence number

detailed timestamp is used

TRUE

See HIL100 CI job

5.4.3 Time Stamp

timestamp is included in packet

TRUE

See HIL100 CI job

5.4.4 Time expectation

as detailed in the specification, several advanced checks are implemented for time expectation

TRUE

See HIL100 CI job

5.4.5 Connectin authentication

unique serial number is used

TRUE

See HIL100 CI job

5.4.6 Feedback msg

no feedback is implemented

TRUE

N/A

5.4.7 Data integrity

CRC + secure hash is used

TRUE

see RER calculations

5.4.8 Redundancy with cross checking

CPU1 and CPU2 independantly calculates hash/CRC

TRUE

See HIL100 CI job

5.4.9 Different data integrity assurance systems

ID code, CRC and secure hash.

TRUE

See HIL100 CI job

Residual Error Rate

RER requirements are stated in 61784-3:2021, 5.8.5. Reference the RER for detailed calculation. Radio communication is handled in sheet “3. GenBlackChannel”.

Revision History

Date

By

Version

Description

2025-08-01

Jesper Ribbe

V01

Initial version