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BL51: Disable Automatic Bank Switching

Information in this article applies to:

  • C51


I wish to implement my own bank switching mechanism. How can I disable the automatic bank switching generated by the linker for inter-bank function calls?


Use the NOJMPTAB (abbreviation: NOJT) directive. The linker will no longer modify function calls to jump to the bank switching code.

Using this directive has the following effects on the linker:

  • The code banking assembler file L51_BANK.A51 is no longer required.
  • The linker does not modify any call instructions.
  • The linker does not generate any warnings if a jump or call is made to another code bank.

You must ensure that the correct bank is selected before making any inter-bank calls or jumps.

You may specify the directive in one of the boxes under Options for Target ... - BL51 Misc - Misc Controls .


  • Refer to NOJMPTAB in the BL51 User's Guide.

Last Reviewed: Thursday, February 25, 2021

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