TMCM-3214, TMCM-3215 Hardware Manual (V0.90 / 2016-JUN-27)
20
Slave
Slave
+5V
pull-up (390R)
termination
+5V
node node
n- 1
n
pull-up (390R)
termination
RS485+ / RS485A
RS485- / RS485B
resistor
(220R)
resistor
(220R)
pull-down (390R)
GND
pull-down (390R)
GND
Figure 4.5: Bus lines with resistor (Bias) network at both ends
Certain RS485 interface converters available for PCs already include these additional resistors (e.g. USB-2-
485 with bias network at one end of the bus).
5.7 CAN
For remote control and communication with a host system the TMCM-3214 provides a CAN bus interface. For
proper operation the following items should be taken into account when setting up a CAN network:
1. BUS STRUCTURE:
The network topology should follow a bus structure as closely as possible. That is, the connection
between each node and the bus itself should be as short as possible. Basically, it should be short
compared to the length of the bus. The TMCM-3214 offers two connectors (RJ45) which are connected
directly to each other and the on-board CAN transceiver. Using both connectors for passing through the
bus will help with keeping a proper bus topology.
Host
Slave
node
1
Slave
Slave
c:>
node node
- 1
n
n
}
termination
resistor
termination
resistor
(120 Ohm)
(120 Ohm)
keep distance as
short as possible
CAN
Figure 5.6: CAN bus structure
2. BUS TERMINATION:
Especially for longer busses and/or multiple nodes connected to the bus and/or high communication
speeds, the bus should be properly terminated at both ends. The TMCM-3214 does not integrate any
termination resistor. Therefore, 120 Ohm termination resistors at both ends of the bus have to be added
externally.
Copyright © 2016, TRINAMIC Motion Control GmbH & Co. KG
TRINAMIC [ TRINAMIC MOTION CONTROL GMBH & CO. KG. ]
