Hi csearcy ,
Thanks for your reply.
I also have some other problem about how encoder input to SM23165D , if you can help me understand it I will really appreciate .
(1)
When I use line driver output signal to my SM23165D port 0 and port 1 ,should I star ground encoder with smart motor ?
(2)
We know Line Driver encoder output TTL 5V phase pair A and /A (or B and /B ) , this complementary pair can be used to eliminate noise signal during transmission .The the document of SM23165D show (A and

phases to be wired to smart motor port0 and port1.
I am wondering if SM23165D can work with TTL 5V signal ,but it don't have the capability to use these complementary signal to eliminate noise .
(2)SM23165D use port 8 and port 9 to output encoder signal ,I want to know which output circuit type is used .
(3)Can port 8(ENC A out) and port9(ENC B out) use as a pulse splitter from external encoder ?