It's a simple matter. The arduino waits for the start string as follows: while (Serial.available() == 0){ }; while(Serial.available()){ while (!(b==Serial.readString())){ } } where b = "start" I send the string from processing as follows: myPort.write("start"); while (myPort.a…

Reading Processing String in Arduino

Robin2 April 3, 2018, 4:05pm 3

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

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