Flex Ray: Coding and Decoding, Media Access Control, Frame and - PowerPoint PPT Presentation

Flex Ray: Coding and Decoding, Media Access Control, Frame and Symbol Processing Seminar: The FlexRay Communication Protocol Chair of Prof. Dr. W. J. Paul Talk by Michael Gerke 27-9-2005

Overview Media access Frame and control (MAC) symbol processing (FSP) Coding and decoding (CODEC) Bus

Media access control (MAC) • Interface: from Controller host interface (Host) to Coding and decoding (CODEC) • Controls timing • Orders ENC to sent symbols

Media access control (MAC) • Controls access to the channels • Guarantees compliance with schedule Communication cycle Static Dynamic Symbol Network segment segment window idle time static slot static slot time organization

Media access control (MAC) Static slot usage: - short idle time - transfer of the frame - long idle time

Media access control (MAC) Assembles frames: - imports data from controller host interface (Host) - assembles header

Coding and Decoding Encoding Decoding Wakeup Channel idle symbol decoding Bit strobing Bus

Encoding (ENC) Frames Transmission start sequence TSS 1 0 Frame coding in static segment

Encoding (ENC) Frames Transmission Frame start start sequence sequence TSS FSS 1 0 Frame coding in static segment

Encoding (ENC) Frames Transmission Frame Byte start start start sequence sequence sequence TSS FSS BSS 1 0 Frame coding in static segment

Encoding (ENC) Frames Transmission Frame Byte start start start sequence sequence sequence TSS FSS BSS Byte 1 0 Frame coding in static segment

Encoding (ENC) Frames Transmission Frame Byte Byte start start start start sequence sequence sequence sequence TSS FSS BSS BSS Byte 1 0 Frame coding in static segment

Encoding (ENC) Frames Transmission Frame Byte Byte start start start start sequence sequence sequence sequence TSS FSS BSS BSS Byte Byte 1 0 Frame coding in static segment

Encoding (ENC) Frames Transmission Frame Byte Byte Frame start start start start end sequence sequence sequence sequence sequence TSS FSS BSS BSS FES Byte Byte 1 0 Frame coding in static segment

Encoding (ENC) Frames Transmission Frame Byte Byte Frame start start start start end sequence sequence sequence sequence sequence TSS FSS BSS BSS FES Byte Byte 1 0 Frame coding in static segment

Encoding (ENC) Symbols Collision avoidance and media access test symbol (CAS/MTS): TSS+0 30 Wakeup symbol (WUS): 0 15-60 +idle 45-180 sent in a wakeup pattern (WUP): WUS 2-63

Bit strobing (BITSTRB) • Takes 8 samples of every bit • Majority voting over last 5 bit samples • Selects 1 sample out of 8 • Low level synchronization

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 11111 1 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 11110 1 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 11100 1 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 11000 0 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 11000 0 voted value 1 from BUS Voting delay 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 10000 0 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 00000 0 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 00001 0 voted value 1 glitch from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 00010 0 voted value 1 glitch from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 00100 0 voted value 1 glitch from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 01000 0 voted value 1 glitch from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 10001 0 voted value 1 glitch from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 00011 0 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 00111 1 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 01111 1 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Majority voting Majority voting over last 5 bit samples voting window 11111 1 voted value 1 from BUS 0 1 voted value 0

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 0

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 1 0 Strobecounter 1 :

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 1 2 0 Strobecounter 2 :

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 1 2 3 0 Strobecounter 3 :

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 1 2 3 4 0 Strobecounter 4 :

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 1 2 3 4 5 0 Strobecounter 5 :

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 Bit strobed: 0 1 2 3 4 5 0 Strobecounter 5 :

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 1 2 3 4 5 6 0 Strobecounter 6 :

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 1 2 3 4 5 6 7 0 Strobecounter 7 :

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 1 2 3 4 5 6 7 8 0 Strobecounter 8 :

Bit strobing: Strobing • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value 1 1 2 3 4 5 6 7 8 1 0 Strobecounter 1 :

Bit strobing: Synchronization • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value BSS 1 1 2 3 4 5 6 7 8 1 0 Strobecounter 1 :

Bit strobing: Synchronization • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value BSS 1 1 2 3 4 5 6 7 8 1 2 0 Strobecounter 2 :

Bit strobing: Synchronization • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value BSS 1 1 2 3 4 5 6 7 8 1 2 3 0 Strobecounter 3 :

Bit strobing: Synchronization • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value BSS 1 1 2 3 4 5 6 7 8 1 2 3 4 0 Strobecounter 4 :

Bit strobing: Synchronization • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value BSS 1 1 2 3 4 5 6 7 8 1 2 3 4 5 0 Strobecounter 5 :

Bit strobing: Synchronization • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS voted value BSS 1 1 2 3 4 5 6 7 8 1 2 3 4 5 6 0 Strobecounter 6 :

Bit strobing: Synchronization • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS sync edge voted value BSS 1 1 2 3 4 5 6 7 8 1 2 3 4 5 6 1 0 Strobecounter 1 :

Bit strobing: Synchronization • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS sync edge voted value BSS 1 1 2 3 4 5 6 7 8 1 2 3 4 5 6 1 2 0 Strobecounter 2 :

Bit strobing: Synchronization • Every 5 th sample out of the 8 samples „strobed“ • Low-level synchronization of strobecounter in BSS sync edge voted value BSS 1 1 2 3 4 5 6 7 8 1 2 3 4 5 6 1 2 3 0 Strobecounter 3 :