need circuit diagrams for rs485 cable

i need circuit diagrams fro rs485 so that i can connect my pc to rs485 of twido plc.i want to send modbus characters to twido, any hints, resourcrs e.t. will help.

rgds
sankey

What port does your Twido have? Available ports are Mini-DIN RS485 or RS232 and a screw terminal RS485. Buying an optional port for the Twido maybe easier than building your own cable especialy if you need to convert from RS23 to RS485.

You can get all of the Twido literature at www.telemecanique.com.

hi all,

i also have some question about twido,
i have mitsubishi programing cable it should be one cable with 9 pin rs232 from pc then convert to rs422 25pin, another cable with
25 pin to mini din ( is it correct ??).
Can i make a make a cable like 25 pin to mini din but convert rs422 to rs485 just jump the terminal internally .
then i can connect my pc to modbus device and also as a programming cable for Telemacanique Twido ??
Any body try it ??

Thanks

B & B Electric has a prett good technical library on all things serial. RS232, RS422, RS485.


Here is a link: http://www.bb-elec.com/technical_library.asp