Functional Description
MPC5200B Users Guide, Rev. 1
Freescale Semiconductor 19-33
Time Segment 2: This segment represents the PHASE_SEG2 of the CAN standard. It can be programmed by setting the TSEG2
parameter to be 2 to 8 time quanta long.

Figure 19-8. Segments within the Bit Time

The Synchronization Jump Width1 can be programmed in a range of 1 to 4 time quanta by setting the SJW parameter.
The above parameters are set by programming the MSCAN Bus Timing Registers (CANBTR0, CANBTR1) (see Section 19.5.3, MSCAN
Control Register 0 (CANCTL0)—MBAR + 0x0900 / 0x980 and Section 19.5.6, MSCAN Bus Timing Register 1 (CANBTR1)—MBAR + 0x0905
/ 0x985).
Table19-34 gives an overview of the CAN compliant segment settings and the related parameter values.
NOTE
It is the user’s responsibility to ensure the bit time settings are in compliance with the CAN standard.

Table19-33. Time Segment Syntax

Syntax Description
SYNC_SEG System expects transitions to occur on the bus during this period.
Transmit Point A node in transmit mode transfers a new value to the CAN bus at this
point.
Sample Point A node in recei ve mode samples the bus at this point. If the three
samples per bit option is selected, then this point marks the position
of the third sample.
1. Reference the Bosch CAN 2.0A/B protocol specification dated September 1991 for bit timing.

Table19-34. CAN Standard Compliant Bit Time Segment Settings

Time Segment 1 TSEG1 Time Segment 2 TSEG2 Synchronization
Jump Width SJW
5 .. 10 4 .. 9 2 1 1 .. 2 0 .. 1
4 .. 11 3 .. 10 3 2 1 .. 3 0 .. 2
Bit Rate fTq
number of Time QuantaÞÞ Þ()-----------------------------------------------------------------------------------------=Þ
SYNC_SEG Time Segment 1 Time Segment 2
1 4 ... 16 2 ... 8
8 ... 25 Time Quanta
= 1 Bit Time
NRZ Signal
Sample Point
(single or triple sampling)
(PROP_SEG + PHASE_SEG1) (PHASE_SEG2)
Transmit Point