mega 2560 can't conect Mobus Relay4 not working why ?

Projects Networking, Protocols, and Devices
1

!!CODE!! Plassssssss..

am just start program. help me

am code mega2560 connect mobusRelay4 with i2c,spi,485half,rs323 a disconnect all code Arduino
Relay board4 can't working WHYWHY?
HELP ME
I
WANT
SOME
CoDeInG
exemples