基于FPGA的嵌入式系统

1 NiosⅡ CPU的体系结构3

1.1 NiosⅡ处理器的结构 (3)

1.2 NiosⅡ处理器的基本组成 (3)

1.3 Debug模块 (3)

1.4 NiosⅡ开发环境简介 (3)

2 IP核4

2.1 SDRAM控制器 (4)

2.2FLASH (5)

3 基于SOPC的温湿度监测系统设计5

3.1 系统总体设计方案 (5)

3.2 SOPC硬件系统设计 (6)

3.3 SOPC软件系统设计 (9)

3.3.1 NiosⅡ软件系统设计 (9)

3.3.2 NiosⅡIDE C/C++Build属性配置 (13)

3.3.3 软件系统的设计流程 (15)

4 实验结果与分析15结论18

SOPC是可编程片上系统，即一种特殊的嵌入式系统。首先它是片上系统（SOC），由单个芯片完成整个系统的主要逻辑功能；其次，它是可编程系统，具有灵活的设计方式，可裁减、可扩充、可升级，并具备软硬件在系统可编程的功能。SOPC是基于FPGA解决方案的SOC，与ASIC的SOC解决方案相比，SOPC系统及其开发技术具有更多的特色。构成SOPC的途径有基于FPGA嵌入IP硬核的系统、基于FPGA嵌入IP软核的系统和基于HardCopy 技术的SOPC系统三种方式。本文介绍基于FPGA的嵌入IP软核的SOPC系统实现方法，设计了一种基于SOPC的温湿度监测系统。通过Quartus II 软件里的SOPC builder把Nios II Processor、Avalon总线、UART、SDRAM_controller、Flash Memory、Avalon三态桥等多个IP核集成生成系统所需的SOPC。传感器扩展板采用Mega8作为主控芯片，用于数据的采集、显示以及和PC的通信。同时配有由SPI总线控制的数码管，可以显示传感器的测量结果，以及与PC通信过程中的具体情况。对外采用波特率为115200的串口进行通信，用户可通过串口向该模块发出各种查询命令以查询传感器的状态。本次设计使用NiosII IDE编写应用程序，发送相应指令，获取温度和湿度的值，同时显示在Console窗口。

关键词：

SOPC技术；FPGA开发板；IP核；温湿度监测；NiosⅡ处理器；Mega8芯片

SOPC is System-On-a-Programmable-Chip, that is a special embedded system: First, it is the system on chip (SOC), which completes the main logic function of the whole system on a single chip; second, it is a programmable system with a flexible design approach which is reducible, scalable, and has the software and hardware in-system programmable functions. SOPC is a kind of special SOC which is based on FPGA solutions and there are more features compared with the SOC and ASIC solutions; three approaches are available to constitute a SOPC: based on embedded hard IP-core FPGA, based on embedded soft IP-core FPGA and based on Hardcopy technology. Each of them has its own characteristics. This article describes the embedded SOPC system based on soft IP core of Altera's FPGA,which is used to design a temperature and humidity monitoring system .Using the SOPC builder of the Quartus II software, we integrate Nios II Processor, Avalon bus, UART, Sdram_controller, Flash Memory, Avalon tristate bridge, and other IP cores to generate the SOPC that the system needs.The sensor expansion board use Mega8 as the main chip for data acquisition, display and PC communication. At the same time, the board has nixietube controlled by the SPI bus, which is used to display the sensor measurements and the specific situation of communication with PC. A user can issue the query command to query the status of the sensor through the115200 serial port of the external communication. This design uses the Nios II IDE to write application,sending the appropriate instructions and obtaining the temperature and humidity values displayed in the Console window.

Keywords:

SOPC technology; the development board of FPGA; IP Core; Temperature and humidity monitoring; NiosⅡprocessor; Mega8 chip