COBHAM GR712RC User Manual

GR712RC-UM, Jun 2017, Version 2.9 208 www.cobham.com/gaisler
GR712RC
Bypassing all the functionality of the Master Channel Generation functionality described above effec-
tively establishes the master channel frame service. The same holds for the Idle Frame generation
described above, allowing the core to generate Idle Frame on the level of the Physical Channel.
27.4.8 All Frame Generation
The All Frame Generation functionality operates on all transfer frames of a Physical Channel. Each of
the individual functions can be bypassed for each frame coming from the DMA interface or idle frame
generation functionality.
The Frame Header Error Control (FHEC) generation can be enabled and disabled by means of a regis-
ter (AOS only).
The Insert Zone is not supported.
Frame Error Control Field (FECF) generation can be enabled and disabled by means of a register.
27.5 Synchronization and Channel Coding Sub-Layer
27.5.1 Attached Synchronization Marker
The 32-bit Attached Synchronization Marker is placed in front of each Transfer Frame as per
[CCSDS-131.0-B-1] and [ECSS-E-ST-50-03C].
An alternative Attached Synchronization Marker for embedded data streams can also be used, its
enabling and bit pattern being programmable via a configuration register.
27.5.2 Reed-Solomon Encoder
The CCSDS recommendation [CCSDS-131.0-B-1] and ECSS standard [ECSS-E-ST-50-03C] specify
Reed-Solomon codes, one (255, 223) code and one (255, 239) code. The ESA PSS standard [PSS013]
only specifies the former code. Although the definition style differs between the documents, the (255,
223) code is the same in all three documents. The definition used in this document is based on the PSS
standard [PSS013].
The Reed-Solomon Encoder implements both codes.
The Reed-Solomon encoder is compliant with the coding algorithms in [CCSDS-131.0-B-1] and
[ECSS-E-ST-50-03C]:
• there are 8 bits per symbol;
• there are 255 symbols per codeword;
• the encoding is systematic:
• for E=8 or (255, 239), the first 239 symbols transmitted are information symbols, and the last 16
symbols transmitted are check symbols;
• for E=16 or (255, 223), the first 223 symbols transmitted are information symbols, and the last 32
symbols transmitted are check symbols;
• the E=8 code can correct up to 8 symbol errors per codeword;
• the E=16 code can correct up to 16 symbol errors per codeword;
• the field polynomial is
• the code generator polynomial for E=8 is
for which the highest power of x is transmitted first;
• the code generator polynomial for E=16 is
f
esa
x x
8
x
6
x
4
x
3
x
2
x 1++++++=

COBHAM GR712RC Specifications

General

Brand	COBHAM
Model	GR712RC
Category	Computer Hardware
Language	English