ARM Technical Support Knowledge Articles

DOES THE RUN-TIME LIBRARY DISABLE INTERRUPTS?

Applies to: C51 C Compiler

Answer


Information in this article applies to:


QUESTION

Are the interrupts disabled in the compiler run-time library?

My program exhibits strange behavior. It appears that interrupt latency is very long during the execution of the sin function. Is there any explanation for this effect?

ANSWER

With a single exception, the run-time library of the Keil C compilers does not disable interrupts.

The exception is found in the C51 Run-Time Library when using large reentrant functions. Interrupts are disabled for 4 CPU instructions (8 CPU cycles) to adjust the large reentrant stack.

Your problem might come from other interupt behavior. For example, high-priority interrupts blocking the execution of lower priority interrupts.

SEE ALSO

Article last edited on: 2005-05-24 10:33:23

Rate this article

[Bad]
|
|
[Good]
Disagree? Move your mouse over the bar and click

Did you find this article helpful? Yes No

How can we improve this article?

Link to this article
Copyright © 2011 ARM Limited. All rights reserved. External (Open), Non-Confidential