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C51: Modifying the Startup Routines

Information in this article applies to:

  • C51 Version 5.50 and later


I need to customize the startup routines that the compiler adds to my program. Can you tell me how to do this?


The startup code is provided in the \C51\LIB directory of your software installation. The files STARTUP.A51 and INIT.A51 are the startup code and variable initialization code respectively. Copy these files into your project directory and modify them as needed. You will find that there are a number of DEFINED variables at the top of the STARTUP.A51 file that make configuration easy



Last Reviewed: Thursday, February 25, 2021

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