Introduction - If you have any usage issues, please Google them yourself
Have not use any controls, control their own serial port, the preparation of a separate class, you can make calls, answer calls, receive call numbers and other operations. It was copied from a book.
Because no control is used, it will not be blocked by the system because of a control vulnerability.
All the communication programs that use controls are not available now. Using this method is the only way to control modem.