I need to send data from one PIC to another PIC by using RS485. As a protocol I use UART. However, I cannot be sure about RS485 transceiver and its circuit. I will be able to supply 5 V and according to this I have found one of the most used option is LT1785 chip. I have these following questions related to this chip:
1) Can this chip (LT1785) also convert RS485 signal to UART or it can only convert UART to RS485?
2) There is no hardware diagram in the datasheet so I have take a look at the internet and some people use 120 ohm resistor between rx and tx pins some people do not. Do I need to put that resistor?
3) In some schematics some people shorted the RE (receiver output enable) and DE (driver output enable) pins. What is the purpose for it? Do I also need to short them?
4) There is a circuit image for UART to RS485 convension. Do I need to change the circuit if I need to use LT1785 for RS485 to UART convension or can I use the circuit in image without changing it?
5) Is there a need for a resistor or a capacitor between Vdd pin to Vdd and a Ground pin to Ground.
PS: I am new to these topics so please excuse if the questions are too simple. Thank you beforehand.