Hi all..
I'm trying to test my RS485 module. When I tried with simple sending, using Arduino Nano as Slave and Arduino Mega as master, the message "GET%" could not be read by slave. Meanwhile, when I swapped, arduino nano became Master and arduino mega became Slave, the command "GET%" can be read, but sending data from slave can only be read half by arduino Nano. Is the cause in my RS485 module or in the code or what?
Please answer, I know this is a silly question but I really need help.
MASTER
#include <SoftwareSerial.h>
#define enTxPin 4 // HIGH: TX and LOW: RX
SoftwareSerial mySerial(2, 3); // RX, TX
void setup() {
Serial.begin(9600);
Serial.println("Starting System");
mySerial.begin(9600);
pinMode(enTxPin, OUTPUT);
digitalWrite(enTxPin, HIGH); // default TX
}
void loop() {
mySerial.print("GET%");
digitalWrite(enTxPin, LOW); // change pin to RX
unsigned long timeLimit = millis();
Serial.println("waiting data");
while (millis() - timeLimit < 3000) {
if (mySerial.available()) {
String dataIN = "";
dataIN = mySerial.readStringUntil('%');
Serial.println(dataIN);
digitalWrite(enTxPin, HIGH); // default TX
break;
}
}
Serial.println("waiting loop");
Serial.println();
delay(5000);
}
SLAVE
#include <SoftwareSerial.h>
#define enTxPin 2 // HIGH: TX and LOW: RX
SoftwareSerial mySerial(11, 12); // RX, TX
void setup() {
Serial.begin(9600);
Serial.println("Starting System");
mySerial.begin(9600);
pinMode(enTxPin, OUTPUT);
digitalWrite(enTxPin, LOW); // default RX
}
void loop() {
if (mySerial.available()) {
String dataIN = "";
dataIN = mySerial.readStringUntil('%');
Serial.println(dataIN);
if (dataIN.substring(0,3) == "GET"){
Serial.println("kirim data ke master");
digitalWrite(enTxPin, HIGH); // change pin to HIGH for TX
String dataOUT = "jarak1#35%";
mySerial.print(dataOUT);
digitalWrite(enTxPin, LOW); // default RX
}
}
delay(10);
}
Result when Arduino Nano becomes Master and Arduino Mega becomes Slave.
Note: Please don't ask why I'm using Serial Software on Arduino Mega, I know I can use Serial1, I'm just trying to copy and paste the code I got on YouTube.
Thanks
