TMCM-1210 Hardware Manual (V0.93 / 2019-FEB-13)
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Copyright © 2015-2019 TRINAMIC Motion Control GmbH & Co. KG
node
n - 1
node
n
Slave
Slave
termination
resistor
(120R)
+5V
GND
pull-up (680R)
pull-down (680R)
RS485- / RS485B
termination
resistor
(120R)
RS485+ / RS485A
Figure 4.7: Bus lines with resistor (Bias) network on one side, only
Or add resistor (Bias) network at both ends of the bus (like Profibus™ termination):
node
n - 1
node
n
Slave
Slave
termination
resistor
(220R)
+5V
GND
pull-up (390R)
pull-down (390R)
RS485- / RS485B
RS485+ / RS485A
termination
resistor
(220R)
+5V
GND
pull-up (390R)
pull-down (390R)
Figure 4.8: 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).