1. Modify Program 28.1 so that it communicates via COM2: (if the PC has one).
2. Using a loopback connection on a serial port, write a program, which sends out the complete ASCII table and checks it against the received characters.
3. Implement a program which has a write buffer system. This should fill a buffer with characters and only send them once every 30 seconds. Modify the program so that the user can enter the delay time.
4. Modify the program in Exercise 28.3.9 so that a user on the receiving computer can specify the filename which is to be sent from the sending program.