Rs232 and rs485

[Guest jack]

When do we use RS485 and RS422, what is the difference in usage Thanks

[panic mode 246]

on 422 you can connect multiple devices, on 232 only two on 422 you can run long distances, on 232 you cannot 422 uses less conductors than 232 and wiring is much simpler why the heck we need 232? it's more common, every PC used to come with it etc.

[Sleepy Wombat 27]

Tried searching on Google ??????? RS485/422/232

[JimRowell 1]

I think Panic Mode was trying to say 485 and typo-ed in 422 by mistake. Just so you are not confused....... 232 is the traditional pc serial port. It's good for short distances and reasonable speeds. Not so good at talking through noise. 422 uses differential pair signalling. Basically it is better at communicating in environments that are electrically noisy such as you'll find around machinery or over longer distances. It requires separate pairs for sending and receiving. 485 is similar to 422 in that it also uses differential pair signalling but it can use a common pair of wires for both sending and receiving data and also it allows multiple devices to share the same wires (called multi-drop). Originally it was a big deal to be able to use only 2 wires for all this. Less important now. Still nice to have the multi-drop capability. Google can give you a lot more info. Jim Rowell

[panic mode 246]

Ooooopss... I posted reply after only glancing the question