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MC68HC12 Datasheet, PDF (344/478 Pages) Motorola, Inc – The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit
MSCAN Controller
• Time segment 1: This segment includes the PROP_SEG and the
PHASE_SEG1 of the CAN standard. It can be programmed by
setting the parameter TSEG1 to consist of 4 to 16 time quanta.
• 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.
The synchronization jump width can be programmed in a range of 1 to 4
time quanta by setting the SJW parameter.
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)).
It is the user’s responsibility to make sure that his bit time settings are in
compliance with the CAN standard. Figure 18-9 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 18-8. Segments within the Bit Time
Technical Data
344
MSCAN Controller
MC68HC912DT128A — Rev 4.0
MOTOROLA