POC實验报告.doc

Computer Organization and Architecture Course Design A parallel output controller School of Information Science and Engineering 2012-3-12 A Parallel Output Controller [POC] 1. Purpose: The purpose of this project is to design and simulate a parallel output controller (POC) which acts an interface between system bus and printer. The Altera’s Quartus II EDA tool is recommended and provided for simulation. Please refer to William Stalling’s “Computer Organization and Architecture, Designing for Performance”, P.65~75; P.185~190. 2. Tasks: POC is one of the most common I/O modules, namely the parallel output controller. It plays the role of an interface between the computer system bus and the peripheral (such as a printer or other output devices). Figure 1 shows the connecting of a printer to the system bus through the POC. The communication between POC and the printer is controlled by a “handshake” protocol illustrated in Figure 2. The handshaking process is described as follows: When the printer is ready to receive a character, it holds RDY=1.The POC must then hold a character at PD (parallel data) port and produce a pulse at the terminal TR (transfer request). The printer will change RDY to 0, take the character at PD and hold the RDY at 0 until the character has been printed (e.g. 5 or 10ms), then set RDY=1 again when it is ready to receive the next character. (Suppose the printer has only a one character “buffer” register, so that each character must be printed before the next character is sent). 3. Top-Level Structure: Figure 3 The overall connection of the simulated printer and POC expressed in the top module form ·Components: Name Explanation printer a simplified printer made up of 74193 and logic gates. POC The parallel output controller. ·Inputs: Name Explanation CLK The system clock for POC and printer. RESET The signal to restart POC and printer. CS Chip Select. In this experiment, CS=1 means we choo