TSS461 ATMEL Corporation, TSS461 Datasheet - Page 12

• Manufacturer Part Number: TSS461
• Description: VAN Data Link Controller
• Manufacturer: ATMEL Corporation

VAN Frame
Figure 8. Hierarchical Access Methods
12
TSS461E
Rank 0
Rank 1
Rank 16
Figure 6. State Encoding
In Figure 6 the pulsed waveforms are shown. In Figure 9 through Figure 15 the low "timeslots"
(i.e. blocks of 16 prescaled clocks) should be replaced by the dominant waveform showed in
Figure 6, if the correct representations for pulsed coding is desired.
Figure 7. VAN Bus Frame
The VAN bus supports three different module (unit) types:
1. The Autonomous module, which is a bus master. It can transmit Start Of Frame (SOF)
2. The Synchronous access module. It cannot transmit SOF sequences, but it can initiate
3. The Slave module, which can only transmit using an in-frame mechanism and can
Autonomous
SOF
sequences, it can initiate data transfers and can receive messages.
data transfers and can receive messages.
receive messages.
SOF
Synchronous
Identifier
ID
ID
Field
VAN BUS
SEQUENCE
VAN BUS
SEQUENCE
VAN BUS
SEQUENCE
NUMBER OF
PRESCALED
CLOCKS
COM
COM
EXT
0
Slave
RAK
Command
2
NORMAL OR PULSED RECESSIVE STATE
DATA
DATA
DATA
NORMAL DOMINANT STATE
4
PUSED DOMINANT ST ATE
R/W
6
8
RTR
10
FCS
FCS
FCS
Field
Data
12
14
EOD
EOD
EOD
Frame
Check
Sum
16
ACK
ACK
ACK
EOD
EOF
EOF
EOF
4194C–AUTO–01/06
ACK
EOF