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    • Updated blank line and italic style authored by Luca Conterio's avatar Luca Conterio
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    HSM.md
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    ......@@ -2,11 +2,11 @@ In **hierarchical state machines** states are organized in a hierarchy.
    This means that states can be themselves other state machines.
    ## Implementation
    In *skyward-boardcore* implementation, the **HSM** class extends the [EventHandler](EventHandler) class, as for FSMs.
    HSM is also a template class, such as FSM.
    The main difference is that we can specify also super-states and perform transitions to them.
    In _skyward-boardcore_ implementation, the **HSM** class extends the [EventHandler](EventHandler) class, as for FSMs.
    HSM is also a template class, such as FSM.
    The main difference is that we can specify also super-states and perform transitions to them.
    Moreover, state methods should return a value of type `State`:
    ```cpp
    enum State
    ......@@ -46,8 +46,8 @@ Available public methods are:
    - **bool testState(State (T::\*test_state)(const Event&))**: test is the state machines is in a specific state (that is passed as a parameter).
    #### Standard Events
    As for FSMs, `EV_ENTRY` and `EV_EXIT` are automatically posted when entering or exiting a state. Moreover, by handling `EV_INIT` in a super-state we can perform the transition to its initial sub-state.
    As for FSMs, `EV_ENTRY` and `EV_EXIT` are automatically posted when entering or exiting a state. Moreover, by handling `EV_INIT` in a super-state we can perform the transition to its initial sub-state.
    You can find the complete implementation of the HSM class in `src/shared/events/HSM.h`.
    ## Example
    ......@@ -56,8 +56,8 @@ This example implements the following very simple hierarchical state machine beh
    ![HSM](images/hsm/hsm.png)
    Whenever the state machine moves to state `S2` (super-state), it will automatically transition to its first sub-state, that is `S3` (`S2` is a state machine itself and `S3` is its initial state).
    We can notice that state `S3` only has a self-loop trasition that is triggered by event `EV_2`. However, if the HSM receives an event `EV_1` while being in state `S3`, the event is handled by state `S2`, which is a super-state of `S3`.
    We can notice that state `S3` only has a self-loop trasition that is triggered by event `EV_2`. However, if the HSM receives an event `EV_1` while being in state `S3`, the event is handled by state `S2`, which is a super-state of `S3`.
    No action is specified for the involved events (`EV_ENTRY`, `EV_EXIT`, `EV_1`, `EV_2`). They simply trigger the transitions.
    #### MyHSM.h
    ......