Easy
PIC
for dsPIC30
®
v7
page 18
communica
tion
Controller Area Network (CAN or CAN bus) is a vehicle bus standard designed to allow microcontrollers
and devices to communicate with each other within a vehicle without a host computer. CAN is a
message-based protocol, designed specifically for automotive applications but now also used in other
areas such as industrial automation and medical equipment. EasyPIC
™
v7 for dsPIC30
®
is equipped with high-
speed MCP2551 CAN Transceiver and a pair of screw terminals which provide microcontrollers with integrated
CAN controller with the necessary physical interface for CAN communication. Make sure to correctly connect negative
and positive differential communication lines before using this module.
5
6
7
8
C10
100nF
R47 10
CN11
CAN_P
CAN_N
TX-CAN
RX-CAN
VCC-5V
1
2
3
4
TXD
VSS
VDD
RXD
Vref
CANL
CANH
Rs
U3
MCP2551
1
2
3
5
4
6
VccA
GND
A
B
DIR
VccB
U4
74LVC1T45
C11
100nF
VCC-5V
VCC-BRD
VCC-5V
C12
100nF
VCC-BRD
VCC-5V
1 2 3 4 5 6 7 8
O
N
SW8
RF0 RF2
1 2 3 4 5 6 7 8
O
N
SW9
RF1 RF3
DATA BUS
Enabling CAN
Figure 8-1:
CAN connection
schematics
CAN communication
In order to enable CAN communi
cation, you
must push SW8.7 (RF0) or SW8.8 (RF2)
and SW9.7 (RF1) or SW9.8 (RF3) to ON
position. This connects the TX and RX lines
to appropriate microcontroller pins and its
CAN module.
communica
tion
