How connect s7 smart200 plc

[Ri0nGo]

hi,I can't to connect s7 smart200 plc. This my code:

func main() {
    handler := gos7.NewTCPClientHandler("192.168.2.123", 2, 0)
    handler.Timeout = 10 * time.Second
    err := handler.Connect()
    if err != nil {
        log.Printf("connect failed, device error: %s\n", err)
        panic(err)
    }
}

error info： 2023/06/15 19:38:16 *net.OpError read tcp 192.168.1.36:62273->192.168.2.123:102: wsarecv: An existing connection was forcibly closed by the remote host. 2023/06/15 19:38:16 connect failed, device error: ISO : Invalid PDU received panic: ISO : Invalid PDU received

Using other client connections can succeed. May I ask if it was written incorrectly？ Looking forward to your reply, thanks.

[Ri0nGo]

I konw how to connect smart200

[iicanf]

@Ri0nGo same error, how to connect?

[Ri0nGo]

修改源码，@iicanf

// NewTCPClientHandlerWithConnType allocates a new TCPClientHandler By Connection type
func NewTCPClientHandlerWithConnType(address string, rack int, slot int, ct string) *TCPClientHandler {
    h := &TCPClientHandler{}
    h.Address = address
    h.Timeout = tcpTimeout
    h.IdleTimeout = tcpIdleTimeout
    h.ConnectionType = connectionTypeOP
    //h.ConnectionType = connectionTypePG // Connect to the PLC as a PG

    remoteTSAP := uint16(h.ConnectionType)<<8 + (uint16(rack) * 0x20) + uint16(slot)
    h.setConnectionParameters(address, 0x0100, remoteTSAP)
    return h
}

[iicanf]

@Ri0nGo 谢谢，好使

[SaltySooda]

same issue！that works！ ps： you also have to make sure that rack and slot number is right（gos7.NewTCPClientHandlerWithConnectType("127.0.0.1", 0, 0, 2)），i use 0，0 for new smart200 plc。 you will get ISO : Invalid PDU received if you set that wrong。