.. include:: ../text_colors.rst
.. toctree::

.. |arrow_pic| image:: ../_static/manual_images/fortiq/other/down_arrow_button.png


.. _manual_high_power_pwm_:

********************************************
High Power PWM Output Interface
********************************************

Module Support
================

The user high power PWM output interface is supported by only the Fortiq-42 modules.

Speed Modules
**************

.. include:: none_checked_table.rst

Servo Modules
**************

.. include:: fortiq_only_table.rst
	
Description
===============

Vertiq's high power PWM output interface provides access to a PWM output driver with read/write accessibility to the frequency, duty cycle, and mode. At the hardware level, this driver is an **open-drain MOSFET without an internal pull up resistor**. The mode parameter determines which portion of the PWM cycle the duty cycle represents, high or low, and is dependent on your application’s hardware setup.

Frequency is described in *Hz*. Frequency has a minimum of 1Hz and is limited to 5000Hz.  

As mentioned above, *mode*'s impact is hardware dependent. If, for example, you use the hardware setup described in :ref:`pwm_testing` , pulling up to V\ :sub:`power` \, mode will function as follows:

With mode set to 0, setting a *duty_cycle* of 75 has the following output:

	.. image:: ../_static/manual_images/fortiq/pwm/pwm_mode_1.png
		:width: 650

With mode set to 1, setting a *duty_cycle* of 75 has the following output: 

	.. image:: ../_static/manual_images/fortiq/pwm/pwm_mode_2.png
		:width: 650

Without pulling up to V\ :sub:`power` \, *mode* will have the opposite impact on the duty cycle. 

Usage
========

.. _pwm_testing:

Initial High Power PWM Output Setup and Testing with IQ Control Center
******************************************************************************
The IQ Control Center provides the easiest way to interact with your module’s PWM peripheral. To do so: 

#. Open IQ Control Center. If you have not installed the program, please follow the instructions in `Getting Started with Speed Motors Using IQ Control Center <https://iqmotion.readthedocs.io/en/latest/tutorials/testing_with_control_center.html>`_. 

#. Connect your module to IQ Control Center

#. Select the Testing Tab on the left side:
	
	.. image:: ../_static/manual_images/fortiq/other/control_center_testing.png

#. Scroll down in the Testing Tab until you find *PWM Output Duty Cycle*

	.. image:: ../_static/manual_images/fortiq/pwm/pwm_testing_tab.png

#. To change a value, either type in your desired value, or use the arrows

#. To save the value to the module click the set arrow icon |arrow_pic|.

#. To test your PWM output, use the following simple circuit

	.. image:: ../_static/manual_images/fortiq/pwm/pwm_sample_circuit.png

	By changing the PWM duty cycle, you should see the LED change intensity.

Vertiq Python API - PWM Interface
****************************************

.. note::
	Please note that the following *PWM output interface* testing was performed with a Fortiq-42 module. Your exact commands may change depending on the module in use.


Vertiq’s PWM interface can also be accessed through Vertiq’s Python API. Through the API you gain read/write access to the PWM parameters duty cycle, frequency, and mode. Please note, only mode and frequency are savable values. To use the API, please use the following steps:

#. If you have never used Vertiq's Python API, you must first set up your local computer to use the Python API using the instructions found at `Getting Started with Python <https://iqmotion.readthedocs.io/en/latest/api_docs/python.html>`_

#. After completing the walkthrough, you can interact with the *pwm_interface* client

#. To read a value, use the *fortiq.get* command. For example, to read the PWM output frequency: 

	.. code-block::

		print(fortiq.get("pwm_interface", "pwm_frequency"))

#. To write a value, use the *fortiq.set* command. For example, to set a duty cycle of 45:
	
	.. code-block::

		fortiq.set("pwm_interface", "duty_cycle", 45)

#. To save a value, use the *fortiq.save* command. For example, to save the PWM mode: 
	
	.. code-block::

		fortiq.save("pwm_interface", "pwm_mode")