Nissan Note E12. Manual - part 416
LAN
SYSTEM
LAN-25
< SYSTEM DESCRIPTION >
[CAN]
C
D
E
F
G
H
I
J
K
L
B
A
O
P
N
• The current flows separately into the termination circuits connected
across the CAN communication system and the termination cir-
cuits drop voltage to generate a potential difference between the
CAN-H line and the CAN-L line.
NOTE:
A signal with no current passage is called “Recessive” and one
with current passage is called “Dominant”.
• The system produces digital signals for signal communications, by
using the potential difference.
The Construction of CAN Communication Signal (Message)
CAN Communication Line
JSMIA0543GB
JSMIA0544ZZ
JSMIA0545ZZ
No.
Message name
Description
1
Start of frame (1 bit)
Start of message.
2
Arbitration of field (11 bit)
Priorities of message-sending are shown when there is a pos-
sibility that multiple messages are sent at the same time.
3
Control field (6 bit)
Signal quantity in data field is shown.
4
Data field (0-64 bit)
Actual signal is shown.
5
CRC field (16 bit)
• The transmitting control unit calculates sending data in ad-
vance and writes the calculated value in a message.
• The receiving control unit calculates received data and judg-
es that the data reception is normal when the calculated val-
ue is the same as the value written in the sent data.
6
ACK field (2 bit)
The completion of normal reception is sent to the transmitting
unit.
7
End of frame (7 bit)
End of message.