Atmel Xplained Pro Evaluation Kit ATSAM4E-XPRO ATSAM4E-XPRO Fiche De Données
Codes de produits
ATSAM4E-XPRO
SAM4E [DATASHEET]
Atmel-11157D-ATARM-SAM4E16-SAM4E8-Datasheet_12-Jun-14
662
The time quantum is calculated as follows:
Note: The BRP field must be within the range [1, 0x7F], i.e., BRP = 0 is not authorized.
To compensate for phase shifts between clock oscillators of different controllers on the bus, the CAN controller
must resynchronize on any relevant signal edge of the current transmission. The resynchronization shortens or
lengthens the bit time so that the position of the sample point is shifted with regard to the detected edge. The
resynchronization jump width (SJW) defines the maximum of time by which a bit period may be shortened or
lengthened by resynchronization.
must resynchronize on any relevant signal edge of the current transmission. The resynchronization shortens or
lengthens the bit time so that the position of the sample point is shifted with regard to the detected edge. The
resynchronization jump width (SJW) defines the maximum of time by which a bit period may be shortened or
lengthened by resynchronization.
Figure 33-5.
CAN Bit Timing
t
BIT
t
CSC
t
PRS
t
PHS1
t
PHS2
+
+
+
=
t
CSC
BRP
1
+
(
) t
peripheral clock
⁄
=
t
PRS
t
CSC
PROPAG
1
+
(
)
×
=
t
PHS1
t
CSC
PHASE1
1
+
(
)
×
=
t
PHS2
t
CSC
PHASE2
1
+
(
)
×
=
t
SJW
t
CSC
SJW
1
+
(
)
×
=
SYNC_
SEG
PROP_SEG
PHASE_SEG1
PHASE_SEG2
NOMINAL BIT TIME
Sample Point
Transmission Point
Peripheral clock
CAN clock
t
CSC
t
PRS
t
PHS1
t
PHS2