Vhandy Technology
GCAN-208 user manual
fiber.
Single-core optical fiber connection requires pairing of A and B devices.
3.3 Connect with CAN bus
GCAN-208 series modules are connected to CAN bus by connecting CAN_H to
CAN_H and CAN_L to CAN_L to establish communication.
The CAN bus network adopts a linear topology, and the two farthest terminals of the
bus need to be installed with 120Ω terminal resistors; if the number of nodes is greater
than 2, the intermediate nodes do not need to install 120 Ω terminal resistors. For
branch connections, the length should not exceed 3 meters. The connection of CAN
bus is shown in Figure 3.7.
Figure 3.7 Topological structure of CAN bus network
Please note
: CAN bus cable can use ordinary twisted pair and shielded twisted pair.
The theoretical maximum communication distance mainly depends on the bus baud
rate. The relationship between the maximum bus length and the baud rate is shown in
Table 3.2. If the communication distance exceeds 1Km, ensure that the cross-sectional
area of the line is greater than Φ 1.0mm2. The specific specifications should be
determined according to the distance. The general rule is to increase the distance as
the distance increases.
Baud rate
Bus length
1 Mbit/s
25m
500 kbit/s
100m
250 kbit/s
250m
125 kbit/s
500m
50 kbit/s
1.0km
20 kbit/s
2.5km
10 kbit/s
5km
5 kbit/s
13km
Table 3.2 Reference table of baud rate and maximum bus length
3.4 CAN bus terminal resistance
In order to enhance the reliability of CAN communication and eliminate the