2 LAB 1: Find and run projects from START’s example browser

The main objective of this hands-on LAB is to showcase START’s example browser, to easily find relevant example projects, download, then compile and run in an IDE.

Following the instructions in the example user guide, the project is exported from START and run in an IDE (a process required to run any of START’s example projects).

Since LABS 2 and 3 will focus on the Event System and Logic (CCL) configurator, we should find an example which includes both these Core Independent Peripherals (CIPs):
  • Peripheral Event System (EVENTS Configurator)
  • Custom Logic (Custom Configurable Logic - CCL)

In addition, the kit you have, the ATtiny817 Xplained Pro, will be a further requirement.

Example Browser

Todo: To browse examples in START:
  1. Open a browser and go to start.atmel.com
  2. Click BROWSE EXAMPLES
  3. Info: There are three primary filters, which can be used individually or together:
    • A free text search: Searches the project name and long description
    • Category search: Lists all projects tagged as belonging to a certain category/technology
    • Board: Lists projects that can run (as is) on a given development kit.
    Figure 2-2. Example Project filters in Atmel START
    1. Using the text search for and searching for “Core” or “Logic”, gives the following results:
      Figure 2-3. Text search using “Core”
      Figure 2-4. Text search using “Logic”
    2. Similarly, the board filter can be used to find example projects specific to the kit.
      Figure 2-5. Board Search
  4. Tip: When clicking on ‘Atmel START example projects for this board…’ from the Atmel Studio 7 Kit Welcome Page, the START example browser is opened with the relevant kit filter applied.
    Figure 2-6. START links in kit welcome page in Atmel Studio 7
    1. Combining the text search with the board constraint, the project options become quite clear.
    Info: The example projects can be filtered based on the categories where each symbol carries its own annotations to meet our application requirements. The project can be further filtered by adding “Custom Logic” into the free text search, “Getting Started” to the category search and “ATTiny817 Xplained Pro” to the board search.
    Figure 2-7. Icon representation of technologies used in example projects
    Our requirements have highlighted a potential project “Getting Started with Core Independent Peripherals”. The project description includes both “custom logic” and “events”. It is also tagged with the “Peripheral Event System” category. Therefore, the project seems to match our requirements.
  5. Todo: To get the next level of detail, click on the User guide button, on the right of the START example browser.
    Figure 2-8. User guide of the shortlisted example
    Result: The project is created in Atmel START and you now have access to the DASHBOARD view:
  6. This project utilizes many of the AVR Core Independent Peripherals (CIP) such as Event system and Custom logic. Moreover, this example combines the CCL, EVSYS, RTC and ADC to filter the signal from a button.
    Tip:
    It is recommended that user guides of example projects in START have at least the following sections:
    • Introduction: Describes what the example project does.
    • Related documents/application notes: Will provide links to these relevant documents.
    • Interface settings: Any specific configuration, e.g. USART baud rate
    • Running the demo: The last section of the user guide is always a short list of steps required to run the project (all projects should be runnable, with very little understanding of how they work).

    Projects in the Getting Started category have links to training materials, while the application notes category project have links to application notes.

Running the example project

The “Download Selected Example” option will provide you with the .atzip format where you can import the project in Atmel Studio, compile and run the same.

Normally it is recommended to hit the Open Selected Example and observe the graphical view of the peripherals. This will also allow you to make modifications to the project configuration.

However, from an understanding of what this example project does, the configuration will later be explored. So initially the steps to simply run the demo will be followed.

  1. Todo: Follow steps 1 and 2, leave the name as default, and click OK.
    Figure 2-9. Running the Demo
    Figure 2-10. Import Atmel Start Project
    Info: Note the .atzip is in the downloads directory, while the project directory is your default Studio 7 project directory.
    Tip: You can also drag and drop the .atzip onto Atmel Studio 7, to open the Import Atmel Start Project wizard.
  2. Todo: Once the project is imported, double-click ‘main.c’ to view the project entry point; this is shown in the figure below.
  3. Todo: Follow step 3.
  4. Todo: Click the Tool icon (), and select the Debugger/Programmer kit.
    Result: A debug tool is associated with the project. We will do the programing step, after connecting and configuring the Data Visualizer.
  5. Todo: Follow steps 4, 5, and 6.

    We have reached a stage to view the output via the Data Visualizer.

  6. Todo: Configure the Data Visualizer
    Open the Data Visualizer from the Tools > Data Visualizer menu.
    1. Click to expand the Serial Port Control Panel
    2. Select the EDBG Virtual COM Port (COMxx)
    3. Check the Open Terminal check box if not selected, then click Connect.
    4. Check Hexadecimal Values to see the ADC conversion results are displayed on the terminal.
    5. Click Start Without Debugging (Ctrl+Atl+F5) to program and run the project.
    Result: For every button press, exactly one hexadecimal result should be displayed on the Data Visualizer.
    Info: Note that the intro section of the example user guide described how to remove the Custom Logic based switch debouncing, by toggling off the comment: 
    //#define NO_DEBOUNCE
  7. Todo: Toggle-off this comment, then program again
    Result: The CCL based switch bounce has now been removed. You may now notice that on occasion two HEX value pop- up per button click, i.e. since two ADC samples were taken.

Further Visualization

In the first part of this lab we enabled and disabled switch debouncing using the Configurable Logic Control (CLC) block. Let’s have a look and what is happening on the pin, using the Data Visualizer.

See the below extract from the ATtiny817 Xplained Pro schematic. Note that DGI GPIO channels are connected to PB5 and PB6 (and that PB5 happens to be SW0). Looking at the USER_BUTTON (SW0), note that there are no pull-ups on this pin.

Before adding a graph to the Data Visualizer, let’s make some space.

Tip: On the Xplained Pro, the Data Gateway Interface (DGI) are channels of the Embedded Debugger (EDBG) that are always looking for data. All that is needed, is to connect and visualize.
  1. Todo: Minimize the Serial Port Control Panel and re-size the terminal window, as shown in the image below.
  2. Todo: Click Connect on the DGI Control Panel.
    Result:

    You will see the visualizer searching for protocols. Then you will see the following results: SPI, TWI (I2C), GPIO and Power.

  3. Todo:
    1. Check GPIO
    2. and Power check boxes
    3. Click Start
    Result:

    The DGI GPIO and Power are visualized on a single graph. Power drawn by board (and LED) is shown if the jumper is set to measure I/O (jumper closest to the switch side of the board).

  4. Next let’s put DGI GPIO0 on a higher resolution graph.
    Todo: Close the Power Analysis window, using the x in the top right of the window. Then, following the image below:
    1. Enable the DGI GPIO check box (if not already enabled)
    2. Double click to add a graph
    3. Drag the GPI GPIO0 onto a new plot
    4. Click Start
    Result:

    You now see what is happening on the pin along with the ADC samples received in the terminal.

LAB 1 Summary

We have now demonstrated the general process of running Atmel START example projects, as well as covering some of the Data Visualizer basics. Example projects may form a key component of your START based development process, especially once you learn to re-configure projects in LAB3. However, let’s first learn how to create new projects from scratch using Atmel START.