摘 要近年来, SD 存储卡在嵌入式产品中的应用越来越广泛, 但 SD 卡接口一般仅集成在 32 位高端处理器中, 一般 51 单片机则由于资源限制没有该接口。因此,如何解决 51 单片机应用系统存取 SD 卡大容量数据就显得很有实际意义。本系统使用 MXT8051F04A 作为单片机与 SD 卡的接口芯片, 采纳 SPI 串行方式对 SD 卡的扇区进行读写,读写过程和结果通过串口调试助手在主机上显示。本论文的核心主要从硬件设计和软件编程两个大的方面介绍了系统的实现。硬件电路设计主要包括 MXT8051F04A 最小系统电路、电源电路、串口电路、SD 卡接口电路。程序采纳 C 语言在 Keil 软件下进行编写、调试,程序主要包括 SD卡扇区读写程序、串口程序等软件模块。系统实现了对 SD 卡扇区的读写,达到了设计的要求和目的。关键字:MXT8051F04A,SD 卡,KeilABSTRACTIn recent years, SD memory card applications in the embedded products more widely, but generally only the integrated SD card interface in 32-bit high-end processor, microcontroller 51 is generally not the interface due to resource constraints. Therefore, how to solve the 51 SCM applications to access data on large-capacity SD cards seem very practical. The system uses MXT8051F04A as SCM and SD card interface chip, using SPI mode on the SD card serial read and write sectors, reading and writing process and results through the serial port on the host display debugging assistant. The core of this thesis, the main hardware and software design introduces two major aspects of the system implementation. Hardware design includes MXT8051F04A minimum system circuit, power circuit, the serial port circuitry, SD card interface circuit. Program using C language under the Keil software write, debug, the program includes reading and writing SD card sector program, serial procedures of software modules. System realizes the SD card read and write sectors, meets the design requirements and objectives. Keyword...