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Chapter 25.  FlexCAN  

25-25

 

Table 25-13 describes the CANCTRL2 fields.

7–0

PRES_DIV Prescaler divide factor. PRESDIV determines the ratio between the system clock frequency and 

the serial clock (S-clock). The S-clock is determined by the following calculation:

The reset value of PRESDIV is 0x00, which forces the S-clock to default to the same frequency 
as the system clock. The valid programmed values are 0 through 255. See Section 25.4.8, “Bit 
Timing” for more information.

7

6

5

3

2

0

Field

RJW

PSEG1

PSEG2

Reset

0000_0000

R/W

R/W

Address

IPSBAR + 0x1C_0009

7–6

RJW Resynchronization jump width. The RJW field defines the maximum number of time quanta a bit time 

may be changed during resynchronization. The valid programmed values are 0 through 3.
The resynchronization jump width is calculated as follows:

Resynchronizaton Jump Width = (RJW + 1) Time Quanta

5–3

PSEG1 PSEG1[2:0] — Phase buffer segment 1. The PSEG1 field defines the length of phase buffer segment 

1 in the bit time. The valid programmed values are 0 through 7.
The length of phase buffer segment 1 is calculated as follows:

Phase Buffer Segment 1 = (PSEG1 + 1) Time Quanta

2–0

PSEG2 PSEG2 — Phase Buffer Segment 2. The PSEG2 field defines the length of phase buffer segment 2 in 

the bit time. The valid programmed values are 0 through 7.
The length of phase buffer segment 2 is calculated as follows:

Phase Buffer Segment 2 = (PSEG2 + 1) Time Quanta

S-clock

fsys

2 PRESDIV + 1

(

)

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