AN943

www.DataSheet4U.com AN943 APPLICATION NOTE SOFTWARE DRIVERS for M29F400 and M29W400 FLASH MEMORIES CONTENTS Introduction The M29F400 Programming Model Modifying code from Am29F400 Generating SGS-THOMSON Code C Library Functions Adapting the Software for the Target System Limitations of the code Connection to Common Microprocessors Conclusion Source Code — INTRODUCTION This application note provides library source code in C for the M29F400 and the M29W400 Flash memories. The M29W400, with a rated power supply of 3V, is a low voltage version of the M29F400 whose power supply is rated at 5V. The M29W400 has slightly slower access times than the M29F400, but the two devices are otherwise very similar. This application note supports both devices and all technical information about the M29F400 also applies to the M29W400, except where otherwise specified. There are two different M29F400 parts, the M29F400B and M29F400T, which will be referred to generically as the M29F400. Similarly the term M29W400 in this application note can refer to either the M29W400T or the M29W400B. The application note includes listings of the source code which is also available in file form. The m29f400a files contain libraries for accessing the M29F400 and the M29W400 Flash memories in 16-bit bus mode, whereas the m29f400b files contain the 8-bit drivers for these devices. An overview of the programming model for the M29F400 (and M29W400) is given. The programming differences between the M29F400 and AM...