Keil Logo

L166: Avoiding Code in Interrupt Vector Space

Information in this article applies to:

  • C166 Version 4.01 and later


The C166 Compiler puts program code in the interrupt vector memory area that is unused. How do I get the compiler to stop doing that?


The C166 Compiler attempts to use every bit of code space available. You may direct the linker to avoid the interrupt vector space by adjusting the starting address for program code in the Target Options dialog box in µVision.


  1. Select the Options for Target... item from the Project menu. The Options... dialog box displays.
  2. In the external memory section, set the start address of your first EPROM/FLASH device to 0x000200. This is already set to 0x000000.
  3. Adjust the size of the device DOWN by 0x200 bytes. For example, if the EPROM is a 64K EPROM, the adjusted size will be 0x00FE00.
  4. Rebuild the project and check the contents of the MAP file. The compile no longer places program code in the interrupt vector space.


  • Refer to CLASSES in the L166 User's Guide.

Last Reviewed: Thursday, February 25, 2021

Did this article provide the answer you needed?
Not Sure
  Arm logo
Important information

This site uses cookies to store information on your computer. By continuing to use our site, you consent to our cookies.

Change Settings

Privacy Policy Update

Arm’s Privacy Policy has been updated. By continuing to use our site, you consent to Arm’s Privacy Policy. Please review our Privacy Policy to learn more about our collection, use and transfers
of your data.