Keil Logo

C51: Interrupt Vector Numbers

Information in this article applies to:

  • C51 Version 3 and Later


Where can I find a list of the interrupt vector numbers to use with C51?


Calculate the interrupt number for C51 interrupt vectors as follows:

(interrupt_address - 3) / 8

So, for interrupt address 33h, the interrupt number would be:

(33h - 3) / 8 = 30h / 8 = 6


Refer to Application Note 103 for more information about interrupt vectors and C51.

Last Reviewed: Wednesday, January 13, 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.