If an interrupt request takes place before the SYSTICK exception, the SYSTICK exceptionwill preempt the IRQ handler. In this case, the OS should not carry out the context switching.
Otherwise the IRQ handler process will be delayed, and for the Cortex-M3, a usage faultcould be generated if the OS tries to switch to Thread mode when an interrupt is active.
Thanks Josepth. I was concerned that buying the new edition would be a simple cover change with errata updates. However, it sounds like enough new material to warrent the purchase. So, off to Amazon... Dave
Hi all,The errata document for the book is updated (see attached file).Joseph
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