Serial Communication Issues on Mega 2560

currently I am using Mega 2560 for a project which needs multi serial communication and I need to convert serial signal into RS-422. Also i am using SerialEvents for serial data acquisition. Now i am facing a problem that in Mega 2560, The serial events are repeatedly calling on serial 1,2 and 3. Even when it is not connected. Any one has any clue about this?

MSA_The_Programmer: The serial events are repeatedly calling on serial 1,2 and 3. Even when it is not connected. Any one has any clue about this?

There is not enough information in that to offer any advice.

Post your program. Tell us what is connected to each of the Serial connections. Do you have GND connections to each device that is communicating with a serial port?

Have a look at the examples in Serial Input Basics - simple reliable ways to receive data.

...R

Also, the serial, or TTL, to RS422 is an electrical thing and needs to be handled off-board with a convertor. Better to consider RS485.

Robin2: Have a look at the examples in Serial Input Basics - simple reliable ways to receive data.

...R

Especially in regards to not using (the useless) SerialEvent. SerialEvent is not an event nor an ISR. SerialEvent is just a call to another subroutine. receiving data from the serial port is best done through Serialx.Available(), where you can then see and control it.