KC868-A4 ,RS232 can not communicate with Max232

[Nantawit]

just find a RS232-RS485 adapter is ok, some seller will have female-male convertor, if not have, you can use 3 line connect with PIN2,3,5 from two interface.

I  have  done  by   RS232 9 Pin Male to Male 1.5  M  Conductor connecting  to  RS232/485  read modbus device  but no  result and  then  used  Max232  to  verify   ,still  no output display  ,in the  first  time  I  think  may  be  Max232  has  the  problem  then  trying  new  one  Max232  ,still  no  output  display ,the  process  testing  as  the  same  testing  at  RS232 port  the   result  should be  the  same ,  I  will  ask  you  this ,  why  ?. I  focus  for  RS485  because  it  can communicate  many  devices , long  range ,stable  that  suitable  in all  applications  even if  the product  A4  has  4-20 mA  (ADC) .