func NewTCPServer(listener net.Listener) *TCPServer {
	s := TCPServer{
		listener: listener,
	}
	return &s
}
NewTCPServer runs TCP server
package modbusone
import (
	"fmt"
	"io"
	"net"
)
const TCPHeaderLength = 6
const MBAPHeaderLength = TCPHeaderLength + 1
type TCPServer struct {
	listener net.Listener
}