.. include:: <mmlalias.txt>


Firmware: Initial Version (Driven By Interrupts)
================================================

.. toctree::
   :hidden:

   main
   fsm
   sensor-switch

.. topic:: Components

   * :doc:`main`
   * :doc:`fsm`
   * :doc:`sensor-switch`

Observations
------------

* Interrupts are nested
* 7 beats 42 and timer
* All logic is in ISRs

  * Reading GPIO state is fine
  * SPI flash write is not (adds more interrupts)
  * Network/CAN IO is not (adds even more interrupts)

Demo: ``tmux`` Layout, Initialization, Startup
----------------------------------------------

For your orientation: an explanation of the terminal screen layout
that is used throughout the course.

.. image:: tmux.jpg

* Left: application

  .. code-block:: console

     $ export PATH=$HOME/My-Builds/jfasch-home-x86_64/trainings/material/soup/linux/why/why-os/shell:$PATH
     $ why-shell ./why-temperature-controller-bare-metal-initial      # or whatever program

* Right 1: "Plant Management"

  .. code-block:: console
     :caption: Set all to "off"

     $ cd /tmp/plant
     $ echo 10 > temperature
     $ echo 0 > cooling
     $ echo 0 > soft-alarm
     $ echo 0 > hard-alarm

* Right 2: Later (CAN-Bus)
* Right 3: Cooling switch

  .. code-block:: console

     $ cd /tmp/plant
     $ watch cat cooling

* Right 4: Soft alarm

  .. code-block:: console

     $ cd /tmp/plant
     $ watch cat soft-alarm

* Right 5: Hard alarm

  .. code-block:: console

     $ cd /tmp/plant
     $ watch cat hard-alarm

Demo: Switch On Cooling
-----------------------

* Right 1: Set temperature above "thermostat high"

  .. code-block:: console

     $ echo 500001 > temperature

* |longrightarrow| cooling on

Demo: Enter Soft Alarm
----------------------

* Right 1: Set temperature above "soft critical"

  .. code-block:: console

     $ echo 1000001 > temperature

* |longrightarrow| soft alarm on (cooling remains on)

Demo: Operator Intervention
---------------------------

* Left: inject "operator button" IRQ 

  .. code-block:: console

     > irq 42

* |longrightarrow| soft alarm off (cooling remains on)

Demo: Sensor Burning
--------------------

* Left: inject "sensor burning" IRQ

  .. code-block:: console

     > irq 7

* |longrightarrow| hard alarm on, cooling off