Set up a hardware and software protocol for communicating between two computers using their parallel ports. Note that you only have the five status lines for input. In order to send a byte, you should break it into two 4-bit "nibbles", and send four bits at a time. The fifth status line should be used for handshaking. The sending computer should indicate on the handshaking line that it has data to send; the receiving computer should acknowledge receipt of the data and tell the sending computer it is ready for the next "nibble".

1. Decide on a handshaking protocol.
2. Wire a cable to implement your protocol.
3. Write a program to transmit and receive data over the parallel port.

1. If a filename is specified on the command line, send that file to the other computer. The receiving computer should create a file with the same file name.
2. If no filename is specified, send anything from the standard input to the other computer. Decide on a method to name the file on the receiving computer.
3. Use interrupts on the recieving computer to receive data sent from the sending computer.