Does this Board works with Arduino with 3.3 V logic?

Hello, I have energy meter with RS485 terminals. https://uploads.disquscdn.c...

Should I Connect to the A/B of the Shield or to the +/- of the shield?

Thanks,

Yes, this interface can be used to send data

Hi, cuould you send us an email [email protected] with your photo of circuit connection, which will be helpful for us to help you.

Hi I got this device it works well with modsim software. I used it with a device that uses modbus rs485 protocol. This device uses an ethernet (RJ 45) cable as an intetrface to transmit data. When I connected pin 4 to terminal A and 5 to terminal B on the shield, nothing happened. Only the Tx LED was blinking. I even connected pin 8 to the shield's ground, and interchanged pin 4 and 5 still no change. What can I do please? Thanks in advance

Hi I would like to ask some guidance for reading ModbusRTU using this product, I looked around and tried but failed miserably, from Mikro DPM380 (http://www.itmikro.com.my/a..., while using SimpleModbusMaster.h (https://github.com/pepsilla....
The following is my Arduino code:
#include <simplemodbusmaster.h>

#define baud 9600
#define timeout 1000
#define polling 100
#define retry_count 10
#define TxEnablePin 2
#define TOTAL_NO_REGISTERS 2
unsigned int regs[TOTAL_NO_REGISTERS];

enum
{
PACKET1,
TOTAL_NO_PACKETS
};
Packet packets[TOTAL_NO_PACKETS];

void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
modbus_construct(&packets[PACKET1], 1, READ_INPUT_REGISTERS, 4019, 1, 0); //FREQUENCY
modbus_configure(&Serial1, baud, SERIAL_8N1, timeout, polling, retry_count, TxEnablePin, packets, TOTAL_NO_PACKETS, regs);
}

void loop() {
// put your main code here, to run repeatedly:
modbus_update();
float frequency;
unsigned long temp = (unsigned long)regs[0] << 16 | regs[1];
frequency = *(float*)&temp;
Serial.print("requests: ");
Serial.print(packets[PACKET1].requests);
Serial.print("\n");
Serial.print("successful_requests: ");
Serial.print(packets[PACKET1].successful_requests);
Serial.print("\n");
Serial.print("exception_errors: ");
Serial.print(packets[PACKET1].exception_errors);
Serial.print("\n");
Serial.print("failed_requests: ");
Serial.print(packets[PACKET1].failed_requests);
Serial.print("\n");
Serial.print("retries: ");
Serial.print(packets[PACKET1].retries);
Serial.print("\n");
Serial.print("connection: ");
Serial.print(packets[PACKET1].connection);
Serial.print("\n");
Serial.print("frequency: ");
Serial.print(frequency/10);
Serial.print(" Hz");
}

Hello,
I have a master which is a plc and has RS485 port and I'm communicating over MODBUS RTU PROTOCOL with several devices each device has his own ID and register addresses, If I use this board can I read variables from arduino and what will be the ID and the register addresses of arduino

I have a load cell, the signal is RS485 and I need to read it with the shield in the arduino. (I have the shield) or i need reading example

Will the arduino be able to do it or can I do it with the board?

Hello. How will I be able to communicate with a modbus device? I have a relay through modbus that I want to send commands to, to toggle it on and off.

Yes,it is. R6 is the rs485 terminal resistor.
They are all VCC,GND,A,B. Just the connector is different. The standard connector is suitable for industrial devices, the mini-connector is suitable for URM04, and the pin header is suitable for DIY experiment.

This seems to be half-duplex only. Is there a full-duplex version of this board anywhere please?