modbus server and device not communicating

#Modbus server and device not communicating serial#
#Modbus server and device not communicating update#
#Modbus server and device not communicating code#

I then tried to add a blocking receive that makes the program wait for the Modbus response before sending the next communication but I am not receiving anything (even though we can see that the gateway is sending a Modbus response back when the communication was successfull) I tried adding MBAP transaction numbers for every communication in the MBAP header of the Modbus communication but it didn't change anything. It looks as though the communication for the device 3,4,5 and 6 where put in the same TCP packet and for some reason, the only Modbus communication that was read from that packet is the last one. This is what the output of Wireshark was (the Ip that ends with 200 is the computer and the one that ends with 107 is the gateway): I looked at the packets that I was sending and receiving to and from the gateway with Wireshark and I think I found where the

#Modbus server and device not communicating update#

If I make the Thread sleep for 30ms between each send, every command works but this is not an option in my case as I need to be able to update every device in a very short amount of time.

Message = (byte)ToHexInDec(command, 'L') //Command low Message = (byte)ToHexInDec(command, 'H') //Command high Message = (byte)ToHexInDec(register, 'L') //Register low Message = (byte)ToHexInDec(register, 'H') //Register high Message = (byte)ToHexInDec(pumpID, 'L') //Pump ID public void SendMessage(int pumpID, int register, int command)

The function SendMessage is as follows, where ClientSocket is a TCP Socket that is connected to the gateway / Modbus slave. In the following code, only the device 1,2 and 6 receive the command. I can send a Modbus command to any of the 6 devices without any problems but the issue happens when I try to send multiple commands in quick interval. The set up I have is the same as in this picture but I have 6 devices connected instead of 2 and will later have 12: Here are the gateway configurations (model EKI-1221-BE): I have a Modbus slave-master relation between computer and the gateway. For now, no validation of CRC upon data receipt.I have a gateway connected to a computer which runs a C# program. I have implemented a method to accept only valid data, based on expected number of response bytes.

Please help me find out what is wrong where!

#Modbus server and device not communicating code#

I have attached my newly implemented code and screenshot of communication trace from modRSsim2 software.

Could you please help me out with where I am lagging?

#Modbus server and device not communicating serial#

I found that if I removed delays and software serial print (mySerial.print()) function statement, then I was able to get response for all four requests that I am sending. I tried checking what is happening inside the function GSM_Send_HTTP_Data() function. Problem 2 : If I call GSM_Send_HTTP_Data() in my code, then data exchange happens for only one modbus request 01,04,00,0D,00,10. However, the order in which the modbus request is sent, is not same as in my code. Problem 1 : In my code, if I comment out the function GSM_Send_HTTP_Data(), then all modbus requests are sent and responses are received for it. However, I am facing two issues as below when the code is tried with ModRSsim2 software:īefore that my code simply reads few sets of registers from modbus slave device and forms a single string and sends to cloud. I have written a code for modbus communication that uses Arduino serial and software serial library.