MC908AZ32ACFUE Datasheet, PDF (276/324 Pages) Freescale Semiconductor, Inc – Microcontrollers

MSCAN Controller (MSCAN08)
The above parameters can be set by programming the bus timing registers, CBTR0–CBTR1, see 24.13.3
MSCAN08 Bus Timing Register 0 and 24.13.4 MSCAN08 Bus Timing Register 1).
NOTE
It is the user’s responsibility to make sure that the bit timing settings are in
compliance with the CAN standard,
Table 24-8 gives an overview on the CAN conforming segment settings and the related parameter values.
NRZ SIGNAL
SYNC
_SEG
1
SYNC_SEG
Transmit point
Sample point
TIME SEGMENT 1
(PROP_SEG + PHASE_SEG1)
4 ... 16
TIME SEG. 2
(PHASE_SEG2)
2 ... 8
8... 25 TIME QUANTA
= 1 BIT TIME
SAMPLE POINT
(SINGLE OR TRIPLE SAMPLING)
Figure 24-8. Segments within the Bit Time
.
Table 24-3. Time Segment Syntax
System expects transitions to occur on the bus during this period.
A node in transmit mode will transfer a new value to the CAN bus at this point.
A node in receive mode will sample the bus at this point. If the three samples
per bit option is selected then this point marks the position of the third sample.
Table 24-4. CAN Standard Compliant Bit Time Segment Settings
Time
Segment 1
5 .. 10
4 .. 11
5 .. 12
6 .. 13
7 .. 14
8 .. 15
9 .. 16
TSEG1
4 .. 9
3 .. 10
4 .. 11
5 .. 12
6 .. 13
7 .. 14
8 .. 15
Time
Segment 2
2
3
4
5
6
7
8
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
SJW
0 .. 1
0 .. 2
0 .. 3
0 .. 3
0 .. 3
0 .. 3
0 .. 3
MC68HC908AZ32A Data Sheet, Rev. 2
276
Freescale Semiconductor