Alan,
What I understand from your post is,
If I have TaskA and TaskB w/ priority 1. Then the program enters TaskA,
then I use Task_setPri to give TaskA a priority of 2.
call Task_sleep for X ms.
If TaskB is in Task_Mode_BLOCKED, the scheduler should stay 'idle' or 'blocked'. If TaskB for some reason is Task_Mode_READY I think the scheduler will jump to that task and the sleep exercise will fail.
After all that restore original priority to TaskA.
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I think I tried something similar some days ago, my program crashed at that time. I will have to revisit to make sure I implemented it correctly.
Regards
-Jose Lopez