TSS463 ATMEL Corporation, TSS463 Datasheet - Page 15

• Manufacturer Part Number: TSS463
• Description: VAN Data Link Controller with Serial Interface
• Manufacturer: ATMEL Corporation

VAN Frame
Figure 13. Hierarchical Access Methods
4102E–AUTO–12/04
Rank 0
Rank 1
Rank 16
Autonomous
SOF
In Figure 11 the pulsed waveforms are shown. In Figure 14 through Figure 20 the low
’timeslots’(i.e. blocks of 16 prescaled clocks) should be replaced by the dominant wave-
form showed in Figure 11 if the correct representations for pulsed coding are desired.
Figure 11. State Encoding
Figure 12. Van Bus Frame
The VAN bus supports three different module (unit) types:
•
•
•
Figure 12 shows a normal VAN bus frame. It is initiated with a Start Of Frame (SOF)
sequence shown in Figure 14. The SOF can only be transmitted by an autonomous
module. During the preamble, the TSS463B will synchronize its bit rate clock to the data
received.
SOF
Synchronous
The Autonomous module, that is a bus master. It can transmit Start of Frame (SOF)
sequences, it can initiate data transfers and can receive messages.
The Synchronous access module. It cannot transmit SOF sequences, but it can
initiate data transfers and can receive messages.
The Slave module, that can only transmit using an in-frame mechanism and can
receive messages.
ID
ID
Identifier
Field
COM
COM
EXT
Slave
RAK
Command
DATA
DATA
DATA
R/W
RTR
FCS
FCS
FCS
Data
Field
EOD
EOD
EOD
ACK
ACK
ACK
Frame
Check
Sum
EOF
EOF
EOF
EOD
TSS463B
ACK
EOF
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