Some processors don’t have explicit control over the global interrupt mask; reenabling it is implicit in the execution of a “return from interrupt” instruction. Is there a workaround?
Yes, on most such processors, you can execute a subroutine call to a “return from interrupt” instruction while still in the master ISR, which will then return to the master ISR, but with interrupts enabled.
Check to see whether the “return from interrupt” affects any other processor state, such as popping a status word from the stack, and prepare the stack accordingly.
Also, beware that another interrupt could occur immediately thereafter, and make sure the master ISR is reentrant beyond that point.
Note: We’ve made the May 2020 issue of Circuit Cellar available as a free sample issue. In it, you’ll find a rich variety of the kinds of articles and information that exemplify a typical issue of the current magazine.
This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may have an effect on your browsing experience.
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
