Xilinx XAPP169 - Manual (Page 12)

12 www.xilinx.com XAPP169 (v1.0) November 24, 1999
1-800-255-7778
MP3 NG: A Next Generation Consumer Platform R
System
Implementation
This section describes how all of these pieces are integrated into a complete system. First
described is the software architecture and the functionality of the key modules. Next is the
architecture and implementation of the logic contained in the Spartan-II FPGA.
Software Architecture
The system software required to implement this device is shown in Figure 14 . The software
components fall into four categories:
• RTOS. A Real Time Operating System is included in the software architecture in order to
simplify the management of resources and concurrent activities.
• BIOS. The Basic Input Output System functions provide low level device management
functions and hardware abstraction.
• Protocol Stacks. These modules implement the network protocol layers for the
communications interfaces.
• Management Processes. These modules implement the application levels functions, and
these run as processes under the RTOS.
ALE
CS
AD[7:0] DATA
RD or WR
ADDR
Figure 13: USBN9602 Read / Write Cycle Timing
(Courtesy National Semiconductor)