hi , i tested both program of arduino RS485 modbus as master and slave communication , great thanks for this project and tutorial ,
but i want to send 16 keys data to simply modbus master software as arduino in slave mode but also need recive data
from modbus like LED on OFF cammand and error massage , here in bothe example Arduino as master and arduino as Slave there are differant library and command are used , in hardware in RS 485 module DE and RE pin is short and in master mode not , so i want ask how i can use this project as slave mode but as transreceiver mode , want send digital keys data and receive cammand etc , please suggest.
