Homework Assignment 2
Due Jan. 27, 1998

1. Decide on a handshaking protocol for transferring data between two computers on the parallel port. (You may use the outline from Messmer if desired.) Draw a timing diagram showing a transfer from one computer to the other. Be sure to indicate how the transmitting computer takes over and releases the bus. Be sure to use the ACK pin on the receiving computer as the "Data available from transmitter" line, so this can later be used to interrupt the receiving computer when data is available.
2. Design and wire up a cable to perform such transfers.
3. Write a (non-interrupt driven) program to transmit data using this scheme. Show that you can type on the keyboard of one computer, and have the keystrokes appear on the screen of the second computer.