ATMEL公司24系列EEPROM编程举例.docVIP

ATMEL公司24系列EEPROM编程举例 作者：尘封往事 文章来源：本站原创 点击数： 2043 更新时间：2006-1-12 13:07:34 NAME?Control_AT24Cxx ; This collection of routines allows an AT89C2051 microcontroller to read; and write the AT24Cxx family of serial CMOS EEPROMS. This version of the; code is compatible only with the AT89C2051 due to the location of the; data buffer and stack in RAM. The code may be modified to work with the; AT89C1051 by relocating or resizing the buffer and stack to fit into the; smaller amount of RAM available in the AT89C1051. Note that the minimum; size of the buffer is determined by the page size of the AT24Cxx.;; All five AT24Cxx device operations are supported. Byte Write, Current; Address Read and Random Read are implemented by the functions WRITE_BYTE,; READ_CURRENT and READ_RANDOM, respectively. Page Write and Sequential Read; are special cases of functions WRITE_BLOCK and READ_BLOCK, respectively.; WRITE_BLOCK and READ_BLOCK process from one byte to the number of bytes; in a page and transfer data between the AT24Cxx and the RAM buffer.;; The code supports multiple AT24Cxx devices per bus, each with a unique; address determined by the wiring of the address pins (A0, A1, A2). The; three-bit programmable address is passed to the WRITE_BYTE, READ_CURRENT,; READ_RANDOM, WRITE_BLOCK and READ_BLOCK functions, where it is combined; with the AT24Cxx fixed address (FADDR) and used to address a device on the; bus. Refer to the AT24Cxx family data sheets for additional information on; device addressing.;; Functions BYTE_FILL, VERIFY_BYTE_FILL, PAGE_FILL and VERIFY_PAGE_FILL are; artifacts from the debug process and serve to illustrate the use of the; device read and write functions with an AT24C64. To modify the code for a; different member of the AT24Cxx family, simply redefine the values of SIZE; (the number of bytes per device) and PSIZE (the number of bytes per page).; To change the fill value, redefine FILL. To change the programmable portion; of the