Checksum error, or CRC error
proasnet opened this issue · comments
I am trying the first model for Modbus RTU to my project. ESP32 Devkit V1 and MAX485 .
Hardware connection working, with another library, but I like to have one library for TCP and RTU. Your TCP library working fine.
As Master (client) I am trying QModRTU, QMod Master and Modbus Poll and in theese all SW, I get error with Checksum or CRC and not working. Please, can you check my model code where is a problem? Its builded from examples.
Thank you.
Code is
#include <HardwareSerial.h>
//#include <SoftwareSerial.h>
#include <ModbusRTU.h>
#define TXenableRS485 21
#define M_RX 34
#define M_TX 32
#define MODBUSRTU_REDE
HardwareSerial RS485(1);
//EspSoftwareSerial::UART RS485;
ModbusRTU mb;
void setup() {
Serial.begin( 115200 );
pinMode( TXenableRS485 , OUTPUT );
digitalWrite( TXenableRS485 , LOW );
RS485.begin( 9600, SERIAL_8N1 , M_RX , M_TX );
//RS485.begin( 9600 , SWSERIAL_8N1 , M_RX , M_TX , false );
mb.begin( &RS485 , TXenableRS485 );
mb.setBaudrate( 9600 );
mb.slave( 1 );
// RTU SERVER
mb.addIreg( 0 ); // analog input
mb.addIreg( 1 ); // analog input
mb.addIreg( 2 ); // analog input
mb.addIreg( 3 ); // analog input
mb.addIreg( 4 ); // analog input
// RTU SERVER
mb.addIsts( 0 ); // digital input
mb.addIsts( 1 ); // digital input
mb.addIsts( 2 ); // digital input
mb.addIsts( 3 ); // digital input
mb.addIsts( 4 ); // digital input
// RTU SERVER
mb.addHreg( 0 ); // holding
mb.addHreg( 1 ); // holding
mb.addHreg( 2 ); // holding
mb.addHreg( 3 ); // holding
mb.addHreg( 4 ); // holding
// RTU SERVER
mb.addCoil( 0 ); // coil
mb.addCoil( 1 ); // coil
mb.addCoil( 2 ); // coil
mb.addCoil( 3 ); // coil
mb.addCoil( 4 ); // coil
}
void loop() {
mb.task(); // Server Modbus TCP queries
mb.Ireg( 0 , 400 ); // analog in
mb.Ireg( 1 , 401 ); // analog in
mb.Ireg( 2 , 402 ); // analog in
mb.Ireg( 3 , 403 ); // analog in
mb.Ireg( 4 , 404 ); // analog in
mb.Ists( 0 , true ); // digital input
mb.Ists( 1 , false ); // digital input
mb.Ists( 2 , true ); // digital input
mb.Ists( 3 , false ); // digital input
mb.Ists( 4 , true ); // digital input
mb.Hreg( 0 , 500 ); // holding
mb.Hreg( 1 , 501 ); // holding
mb.Hreg( 2 , 502 ); // holding
mb.Hreg( 3 , 503 ); // holding
mb.Hreg( 4 , 504 ); // holding
Serial.println ( "coil 0: " + String( mb.Coil( 0 )) + " coil 2: " + String( mb.Coil( 1 )) + "coil 2: " + String( mb.Coil( 2 )) + " coil 3: " + String( mb.Coil( 3 )));
yield();
}
I suspect it was some wiring or line speed related issue
I was testing the library with cheap transceivers with no problem up to 1Mbit speed. Auto RX-TX (with no re-de) one was working only at 9600.