Building
========

Assuming that you have all of the required components listed in the 
:doc:`components` sections, building the system is relatively
straightforward.

.. _start_build_solder_jumpers:

Setting the solder jumpers
--------------------------

Before using the interface boards for the first time, you will need to set the 
four solder jumpers on the 
:ref:`microcontroller interface board <_start_components_custom_microcontroller_board>`,
according to the temperature sensing breakout boards you intend to use. 

Each solder jumper has three pads, which collectively form a switch. To use the
Adafruit MAX31865 (RTD sensors) at Header 1, for example, you should solder the
middle pad to the 'RTD' pad on the right. Likewise, for the MAX31856 
(Thermocouple sensors), solder the middle pad to the 'TC' pad on the left. All
four solder jumpers can be continuously reconfigured, as required.

.. figure:: /images/SolderJumperCloseup.png
    :width: 800px
    :align: center
    :alt: Solder jumpers on the interface board, with SJ2 configured for RTD 
        sensors.

    **Solder jumpers on the interface board, with example of SJ2 configured for 
        RTD sensors.**

.. _start_build_connecting:

Connecting up the boards
------------------------

Inter-board connections
^^^^^^^^^^^^^^^^^^^^^^^

The figure below shows the connections for the interface boards:

.. figure:: /images/BoardConnectionDiagram.png
    :width: 800px
    :align: center
    :alt: Connections for the interface boards

For the wires connecting the DC Power Supply, make sure to use an appropriate 
gauge, keeping in mind the current draw the thermoelectric module is likely to
have (5A is a safe, if slightly overly overcautious, assumption).


Motor controller interface board
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

After connecting the HAT-MDD10A to the 
:ref:`motor controller interface board <_start_components_custom_motor_board>`, 
via the the 40-pin header, the vertically stacked terminal blocks should be
connected together like so (once again taking into consideration the current 
draw):

.. figure:: /images/MotorHatWiring.png
    :width: 800px
    :align: center
    :alt: Stacked terminal blocks

It's a good idea to use slightly longer wires for the connections between the 
terminals, so that the motor controller can be lifted off the interface board,
without having to continuously disconnect and reconnect the wires.


Temperature breakout boards
^^^^^^^^^^^^^^^^^^^^^^^^^^^

The temperature breakout boards connect to the microcontroller interface board
via the female 8-pin headers. In the case of the MAX31856, which has a 9-pin
male header, the 9th pin (DRDY) is not used, so can be left unconnected.