Settimino can no longer connect to PLC after 4 faliures

Development Libraries
1

I am using Settimino library with Arduino Opta to connect to multiple siemens PLCs, but I have noticed if I get 4 errors when connecting to PLC it can then no longer connect to other plcs

In code below I first try to connect to PLC that doesn't exist (192.168.1.99) three times
and then in loop I can connect to PLC that does exist (192.168.1.90) in loop as many times as loop runs.
if I try to connect to nonexistant PLC 4 times, then in loop I can't connect to PLC that exist.
the same happens if I only am connecting to PLC that exists, but I get random connection errors, such as pluging the cable out and back in.
Is there a way to make sure that once you get 4 errors you can continue using S7Client?

Each client uses a socket (via the EthernetClient object) so you can instantiate up to four clients or less if you are instantiating other Ethernet object (or derived) in the same project.

I think error is somewhat connected to this line from Settimino documentation but I am not sure how to clear those clients

#include <Ethernet.h>
#include <SPI.h>
#include "Settimino.h"

byte mac[] = { 0xA8, 0x61, 0x0A, 0x50, 0x46, 0xA3 };
IPAddress ip(192, 168, 1, 233);
IPAddress myDns(192, 168, 1, 1);
IPAddress gateway(192, 168, 1, 1);

EthernetClient client;

void setup() {
  Serial.begin(9600);
  while (!Serial) {;}
  Serial.println("Starting setup");
  SetupEthernet();
  ReadS7(IPAddress(192,168,1,99));
  ReadS7(IPAddress(192,168,1,99));
  ReadS7(IPAddress(192,168,1,99));
  //ReadS7(IPAddress(192,168,1,99));
}

void loop() {
  delay(1000);
  ReadS7(IPAddress(192,168,1,90));
}
void SetupEthernet() {
  Serial.println("Initialize Ethernet:");
  if (Ethernet.begin(mac, ip, myDns, gateway) == 0) {
    Serial.println("Failed to configure Ethernet");
  } else {
    Serial.print("IP: ");
    Serial.println(Ethernet.localIP());
  }
  delay(1000);
}

void ReadS7(IPAddress ip)
{
  int area = S7AreaDB;
  S7Client *plcClient = new S7Client();
  if(ConnectPLC(plcClient, ip,0,1))
  {
  }
  plcClient->Disconnect();
  delete plcClient;
  plcClient = NULL;
  return;
}

bool ConnectPLC(S7Client *plcClient,IPAddress ip, int rack, int slot) {
  int Result = plcClient->ConnectTo(ip, rack, slot);
  Serial.print("Connecting to ");
  Serial.println(ip);
  if (Result == 0) {
    Serial.println("You are connected with Your PLC");
  } else {
    Serial.print("Connection error: ");
    Serial.println(Result);
    plcClient->Disconnect();
  }
  return Result == 0;
}
2

I have no idea what you're talking about (not your fault, I'm just not familiar with the stuff that you're using) and hence can't help you but I think that below is a serious flaw in your code

If you use dynamic memory allocation with malloc or new, you should always check the result before using it.

3

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