adwsystems:
Modbus RTU specifies how the software interprets the data. Two different things. Don't get them confused.
Modbus RTU seems an optional layer, is that right? Or this is how Arduino Serial works?
Do I need to worry about Modbus if I just use Serial.print and Serial.available?
The motor can perfectly send and receive commands over RS485. No Master/Slave concept there (sending "ready" string when in position, not by request. Should the Pseudo-code work then?