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Made relation between priority and number explicit
When quickly reading through the priorities chapter, I couldn't find in which order the priorities were, so I assumed it was the same as in the hardware. In the cortex-m hardware, interrupts with the **lower** priority number will preempt the other interrupts. RTIC does the reverse, so I think it's good to be more explicit about it.
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@ -119,10 +119,13 @@ The static priority of each handler can be declared in the `task` attribute
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using the `priority` argument. Tasks can have priorities in the range `1..=(1 <<
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using the `priority` argument. Tasks can have priorities in the range `1..=(1 <<
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NVIC_PRIO_BITS)` where `NVIC_PRIO_BITS` is a constant defined in the `device`
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NVIC_PRIO_BITS)` where `NVIC_PRIO_BITS` is a constant defined in the `device`
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crate. When the `priority` argument is omitted, the priority is assumed to be
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crate. When the `priority` argument is omitted, the priority is assumed to be
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`1`. The `idle` task has a non-configurable static priority of `0`, the lowest
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`1`. The `idle` task has a non-configurable static priority of `0`, the lowest priority.
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priority.
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When several tasks are ready to be executed the one with *highest* static
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> A higher number means a higher priority in RTIC, which is the opposite from what
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> Cortex-M does in the NVIC peripheral.
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> Explicitly, this means that number `10` has a **higher** priority than number `9`.
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When several tasks are ready to be executed the one with highest static
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priority will be executed first. Task prioritization can be observed in the
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priority will be executed first. Task prioritization can be observed in the
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following scenario: an interrupt signal arrives during the execution of a low
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following scenario: an interrupt signal arrives during the execution of a low
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priority task; the signal puts the higher priority task in the pending state.
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priority task; the signal puts the higher priority task in the pending state.
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