I’ve been wanting to play around with an Arduino for quite some time. Here’s what I want to do… send and receive data via RS-485 and have a simple webpage gui that will be able to display the results and send the commands remotely. I’m thinking of using an Arduino Mega 2560 with an ethernet shield. Does this sound feasable before I go and buy the wrong stuff? Will I need a MAX485 chip or similar?
Thanks
What you’ve suggested sounds reasonable. There are a bunch of different RS-485 / RS-422 chips you could use, connected to one of the UARTs on the Arduino.
I often use RS-422, since RS-485 is half-duplex, and trickier to implement in software.
You can also buy RS-232 to RS-485 inline converters. Look for them at places line B&B Electronics. http://www.bb-elec.com/product_family.a … b&Trail=11
fll-freak:
You can also buy RS-232 to RS-485 inline converters…
Indeed, but I don't think RS-*232* is relevant here (this is different to RS-*422*), since the OP wants to connect an Arduino directly (which just has logic levels on its UARTs).
but I don’t think RS-232 is relevant here
It might be a simpler LEGO block construction to use a SFE logic level to RS-232 converter followed by a B&B RS-232 to RS-485 converter than to find an integrate an RS-485 chip.
Ok, never mind. Just found this from SFE: http://www.sparkfun.com/products/10124. Much simpler than my two stage approach.
I have .C code that runs in Linux and updates a webpage. How similar is this code to what I will need for the Arduino? I’ve attached the code if anyone wants to take a look.
Thanks