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RS 485 termination?
#1
Hi
What is the internal circuit of RS485 in LM4 like? Is the line terminated internally? Or it is in high-impedance state and the termination must be done by external resistor(s)?

In case the line is not internally terminated do you have a recommendation how to correctly terminate the line?

Are RS485 lines electrically isolated between each other and to other lines especially to KNX bus?

Thank you
LM5Lp, firmware: 2018.08.22 and 2021.12.15, FlashSYS v2, ARMv7 Processor rev 5 (v7l), kernel 4.4.151 and 4.4.259
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#2
There's no internal termination. If you need it, then place 120ohm resistors on both line ends. KNX is completely isolated from other system components, RS-485 is not.
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