研究32位Cortex-M3 MCU开发技术

本文介绍了LM3S9B96 MCU Cortex-M3处理器方框图以及Stellaris? LM3S9B96开发板主要特性，方框图，电路图和扩展板电路图。

　　德州仪器（TI）公司Stellaris?所提供一系列的微控制器是首款基于ARM? CortexTM-M3的控制器，它们为对成本尤其敏感的嵌入式微控制器应用方案带来了高性能的32位运算能力。这些具备领先技术的芯片使用户能够以传统的8位和16位器件的价位来享受32位的性能，而且所有型号都是以小占位面积的封装形式提供。

　　LM3S9B96微控制器的优势还在于能够方便的运用多种ARM的开发工具和片上系统（SoC）的底层IP应用方案，以及广大的用户群体。另外，该微控制器使用了兼容ARM Thumb?的Thumb2指令集来减少存储容量的需求，并以此达到降低成本的目的。最后，LM3S9B96微控制器与Stellaris?系列的所有成员是代码兼容的，这为用户提供了灵活性，能够适应各种精确的需求。

　　为了能够帮助用户产品快速的上市，德州仪器（TI）公司提供了一整套的解决方案，包括评估和开发板、白皮书和应用笔记、方便使用的外设驱动程序库、以及强大的支持、销售和分销商网络。

　　LM3S9B96目标应用：

　　The Stellaris family is positioned for cost-conscious applications requiring significant control processing and connectivity capabilities such as:

　　Remote monitoring

　　Electronic point-of-sale （POS） machines

　　Test and measurement equipment

　　Network appliances and switches

　　Factory automation

　　HVAC and building control

　　Gaming equipment

　　Motion control

　　Medical instrumentation

　　Fire and security

　　Power and energy

　　Transportation

　
图1.Stellaris LM3S9B96方框图

　　图2.Stellaris LM3S9B96 Cortex-M3处理器方框图

　　Stellaris? LM3S9B96开发板

　　The Stellaris? LM3S9B96 Development Board provides a platform for developing systems around the advanced capabilities of the LM3S9B96 ARM? Cortex?-M3-based microcontroller.

　　The LM3S9B96 is a member of the Stellaris Tempest-class microcontroller family. Tempest-class devices include capabilities such as 80 MHz clock speeds, an External Peripheral Interface （EPI） and Audio I2S interfaces. In addition to new hardware to support these features, the DK-LM3S9B96 board includes a rich set of peripherals found on other Stellaris boards.

　　The development board includes an on-board in-circuit debug interface （ICDI） that supports both JTAG and SWD debugging. A standard ARM 20-pin debug header supports an array of debugging solutions.

　　The Stellaris? LM3S9B96 Development Kit accelerates development of Tempest-class microcontrollers. The kit also includes extensive example applications and complete source code.

LM3S9B96开发板主要特性：

　　The Stellaris? LM3S9B96 Development Board includes the following features.

　　Simple set-up—USB cable provides debugging, communication, and power

　　Flexible development platform with a wide range of peripherals

　　Color LCD graphics display

　　– TFT LCD module with 320 x 240 resolution

　　– Resistive touch interface

　　80 MHz LM3S9B96 microcontroller with 256 K Flash, 96 K SRAM, and integrated Ethernet MAC+PHY, USB OTG, and CAN communications

　　– – 8 MB SDRAM （plug-in EPI option board）

　　– – EPI break-out board （plug-in option board）

　　1 MB serial Flash memory

　　Precision 3.00 V voltage reference

　　SAFERTOS? operating system in microcontroller ROM

　　I2S stereo audio codec

　　– Line In/Out

　　– Headphone Out

　　– Microphone In

　　Controller Area Network （CAN） Interface

　　10/100 BaseT Ethernet

　　USB On-The-Go （OTG） Connector

　　– Device, Host, and OTG modes

　　User LED and push button

　　Thumbwheel potentiometer （can be used for menu navigation）

　　MicroSD card slot

　　Supports a range of debugging options

　　– Integrated In-circuit Debug Interface （ICDI）

　　– JTAG, SWD, and SWO all supported

　　– Standard ARM? 20-pin JTAG debug connector

　　USB Virtual COM Port

　　Jumper shunts to conveniently reallocate I/O resources

　　Develop using tools supporting Keil? RealView? Microcontroller Development Kit （MDK-ARM）， IAR Embedded Workbench, Code Sourcery GCC development tools, Code Red Technologies development tools, or Texas Instruments’ Code Composer Studio? IDE

　　Supported by StellarisWare? software including the graphics library, the USB library, and the peripheral driver library

　　An optional Flash and SRAM memory expansion board （DK-LM3S9B96-EXP-FS8） is also available for use with the DK-LM3S9B96 development board

　　– Works with the External Peripheral Interface （EPI） of the Stellaris microcontroller

　　– Provides Flash memory, SRAM, and an improved performance LCD interface

　　LM3S9B96开发板包括：

　　The Stellaris? LM3S9B96 Development Kit contains everything needed to develop and run a range of applications using Stellaris microcontrollers:

　　LM3S9B96 development board

　　8 MB SDRAM expansion board

　　EPI signal breakout board

　　Retractable Ethernet cable

　　USB Mini-B cable for debugger use

　　USB Micro-B cable for OTG-to-PC connection

　　USB Micro-A to USB A adapter for USB Host

　　USB Flash memory stick

　　microSD Card

　　20-position ribbon cable

　　CD containing:

　　– A supported version of one of the following （including a toolchain-specific Quickstart

　　guide）：

　　Keil? RealView? Microcontroller Development Kit （MDK-ARM）

　　IAR Embedded Workbench

　　Code Sourcery GCC development tools

　　Code Red Technologies development tools

　　Texas Instruments’ Code Composer Studio? IDE

　　– Complete documentation

　　– Quickstart application source code

　　– Stellaris? Firmware Development Package with example source code

　　

图3.LM3S9B96开发板外形图

图4.DK-LM3S9B96开发板方框图

图5.DK-LM3S9B96开发板电路图(1)

图6.DK-LM3S9B96开发板电路图(2)

图7.DK-LM3S9B96开发板电路图(3)

图8.DK-LM3S9B96开发板电路图(4)

图9.DK-LM3S9B96开发板电路图(5)

图10.DK-LM3S9B96开发板电路图(6)

图11.用于DK-LM3S9B96的FLASH/SRAM/LCD IF扩展板电路图(1)

　　图12.用于DK-LM3S9B96的FLASH/SRAM/LCD IF扩展板电路图（2）