MC68HC912DG128 Datasheet, PDF (331/452 Pages) Motorola, Inc – Microcontrollers

Freescale Semiconductor, Inc.
MSCAN Controller
Clock System
The above parameters can be set by programming the bus timing
registers (CBTR0–1, see msCAN12 Bus Timing Register 0 (CBTR0) and
msCAN12 Bus Timing Register 1 (CBTR1)).
NOTE:
It is the user’s responsibility to make sure that his bit time settings are in
compliance with the CAN standard. Figure 17-9 gives an overview on
the CAN conforming segment settings and the related parameter values.
NRZ Signal
SYNC
_SEG
1
Time segment 1
(PROP_SEG + PHASE_SEG1)
4 ... 16
8... 25 Time Quanta
= 1 Bit Time
Time Seg. 2
(PHASE_SEG2)
2 ... 8
Transmit point
Sample point
(single or triple sampling)
Figure 17-8. Segments within the Bit Time
Figure 17-9. CAN Standard Compliant Bit Time Segment Settings
Time Segment 1 TSEG1 Time Segment 2 TSEG2
5 .. 10
4 .. 9
2
1
4 .. 11
3 .. 10
3
2
5 .. 12
4 .. 11
4
3
6 .. 13
5 .. 12
5
4
7 .. 14
6 .. 13
6
5
8 .. 15
7 .. 14
7
6
9 .. 16
8 .. 15
8
7
Synchron.
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
MC68HC912DG128 — Rev 3.0
MOTOROLA
MSCAN Controller
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Go to: www.freescale.com
Technical Data
331