I am trying to pull information from the Renogy DC-DC Battery Charger via RS485 and Modbus communication. I am using the Arduino MKR WIFI 1010 and the Arduino MKR 485 Shield with it. In order to communicate I am using a RJ45 cable. My problem is when I run my code (Attached below), I get an error message saying, "Connection timed out." Does anyone have any fixes?
#include "ArduinoRS485.h"
#include "ArduinoModbus.h"
float voltage;
void setup() {
Serial.begin(9600);
delay(1500);
if (!ModbusRTUClient.begin(9600)) {
Serial.println("- Failed to start Modbus RTU Client!");
while (1);
}
}
void loop() {
voltage = readVoltage();
Serial.print("Battery Voltage: ");
Serial.print(voltage);
Serial.println(" V");
delay(3000); // Delay 1 second between readings
}
float readVoltage() {
float voltage = 0.0;
// Send reading request over RS485 to address 0x01 and register 0x0101 (example)
if (!ModbusRTUClient.requestFrom(0x01, INPUT_REGISTERS, 0x0101, 1)) {
// Error handling
Serial.print("- Failed to read the voltage! Error: ");
Serial.println(ModbusRTUClient.lastError());
} else {
// Response handler
uint16_t highWord = ModbusRTUClient.read();
uint16_t lowWord = ModbusRTUClient.read();
uint32_t millivolt = (highWord << 16) | lowWord; // Combine high and low words
voltage = millivolt / 1000.0; // Convert millivolts to volts
}
return voltage;
}
