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AT89C51CC03
4182O–CAN–09/08
Table 62. CANBT3 Register
CANBT3 (S:B6h)
CAN Bit Timing Registers 3
Note:
The CAN controller bit timing registers must be accessed only if the CAN controller is dis-
abled with the ENA bit of the CANGCON register set to 0.
No default value after reset.
7654
3210
-
PHS2 2
PHS2 1
PHS2 0
PHS1 2
PHS1 1
PHS1 0
SMP
Bit
Number
Bit Mnemonic Description
7-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
6-4
PHS2 2:0
Phase Segment 2
This phase is used to compensate for phase edge errors. This segment can
be shortened by the re-synchronization jump width.
Phase segment 2 is the maximum of Phase segment 1 and the Information
Processing Time (= 2TQ).
3-1
PHS1 2:0
Phase Segment 1
This phase is used to compensate for phase edge errors. This segment can
be lengthened by the re-synchronization jump width.
0SMP
Sample Type
0 - once, at the sample point.
1 - three times, the threefold sampling of the bus is the sample point and twice
over a distance of a 1/2 period of the Tscl. The result corresponds to the
majority decision of the three values.
Tphs2 = Tscl x (PHS2[2..0] + 1)
Tphs1 = Tscl x (PHS1[2..0] + 1)