I am beginner of Arduino.
i brought the linksprite RS485 Shield for Arduino.
Need any library to use the rs485 shield.thank you very much
http://www.linksprite.com/product/showproduct.php?id=175&lang=cn
Thank you
Not sure what that Shield does, but, is this what you need?
And here you have some examples without libraries Error, Electronic & Electronics Components Depot United States
RS485 is a differential high-speed serial transmission-line protocol. Only information I can get from that
website is the photo! Seems to have a single channel - clearly pin 2 is connected to it, but there is no
doubt another pin (RS485 transceivers have a data and a direction connection, typically, so two
digital pins are enough to interface them).
The standard is only hardware so you can use it as you please, but expect 10MHz over 100m or more without
any difficulty, and several km with lower baud rates! You need termination at each end of the line, but its
not clear if this shield includes termination (you must have no termination for a multidrop setup for the
intermediate points, only at the ends).
The connection must be via twisted pair with characteristic impedance of around 100 ohms. One pair from
a CAT-5 cable would be suitable for instance.
In reality very long distance runs will need opto-isolation at the receiving end to filter out common-mode
voltages.