mc9s12xd256 Freescale Semiconductor, Inc, mc9s12xd256 Datasheet - Page 466

• Manufacturer Part Number: mc9s12xd256
• Description: Hcs12x Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Chapter 10 Freescale’s Scalable Controller Area Network (S12MSCANV3)
The synchronization jump width (see the Bosch CAN specification for details) can be programmed in a
range of 1 to 4 time quanta by setting the SJW parameter.
The SYNC_SEG, TSEG1, TSEG2, and SJW parameters are set by programming the MSCAN bus timing
registers (CANBTR0, CANBTR1) (see
and
Table 10-35
10.4.4
10.4.4.1
The MSCAN module behaves as described within this specification in all normal system operation modes.
10.4.4.2
The MSCAN module behaves as described within this specification in all special system operation modes.
466
Section 10.3.2.4, “MSCAN Bus Timing Register 1
Time Segment 1
Modes of Operation
gives an overview of the CAN compliant segment settings and the related parameter values.
Normal Modes
Special Modes
5 .. 10
4 .. 11
5 .. 12
6 .. 13
7 .. 14
8 .. 15
9 .. 16
It is the user’s responsibility to ensure the bit time settings are in compliance
with the CAN standard.
Transmit Point
Sample Point
SYNC_SEG
Syntax
Table 10-35. CAN Standard Compliant Bit Time Segment Settings
TSEG1
3 .. 10
4 .. 11
5 .. 12
6 .. 13
7 .. 14
8 .. 15
4 .. 9
System expects transitions to occur on the CAN bus during this
period.
A node in transmit mode transfers a new value to the CAN bus at
this point.
A node in receive mode samples the CAN bus at this point. If the
three samples per bit option is selected, then this point marks the
position of the third sample.
Table 10-34. Time Segment Syntax
MC9S12XDP512 Data Sheet, Rev. 2.17
Time Segment 2
Section 10.3.2.3, “MSCAN Bus Timing Register 0
2
3
4
5
6
7
8
NOTE
(CANBTR1)”).
Description
TSEG2
1
2
3
4
5
6
7
Synchronization
Jump Width
1 .. 2
1 .. 3
1 .. 4
1 .. 4
1 .. 4
1 .. 4
1 .. 4
Freescale Semiconductor
(CANBTR0)”
0 .. 1
0 .. 2
0 .. 3
0 .. 3
0 .. 3
0 .. 3
0 .. 3
SJW