SAMA7G54-EK - Getting Started with MPLAB® Harmony v3 Development: CSP Application: pio_led_on_off_interrupt

Last modified by Microchip on 2024/06/24 06:29

Introduction

In this training topic, you will download, configure, and build an MPLAB® Harmony v3 application example using MPLAB X Integrated Development Environment (IDE) to run on the SAMA7G54-EK Evaluation Kit in debug mode. This scenario is typical of project development steps of coding, building, and debugging.  

While in debug mode, the second-stage bootloader, at91bootstrap, is used by MPLAB X IDE to initialize DRAM so that it can continue loading the MPLAB Harmony 3 project binary (harmony.bin). Once the project has been loaded onto the SAMA7G54-EK, MPLAB X IDE can be used to run and debug the application.

Once a project has been fully developed, the application is cleaned and built for production. The application binary (harmony.bin) is loaded by at91bootstrap from Non-Volatile Memory (NVM), such as SD Memory Card, e.MMC, NAND and NOR Flash memories. Training topics on how to write binary files to NVM are given in the "What’s Next?" section below. 

MPLAB Harmony v3 Application

This CSP Application example demonstrates the control of peripherals using Peripheral Libraries (PLIBs) with minimal external dependencies.  

This application uses the PIO Peripheral library to generate callback on switch press and release and drives the GPIO pin connected to the RGB LED to indicate the switch status. The RGB LED is turned ON when the switch is pressed and turned OFF when the switch is released. 

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Prerequisites

​This training was developed with MPLAB X IDE v6.15 and XC32 v4.30.

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Hardware

For this training, you will use the SAMA7G54-EK Evaluation Kit.

SAMA7G54-EK Evaluation Kit

See the SAMA7G54-EK Evaluation Kit – Features” page. 

Setup the SAMA7G54-EK as listed below to the host computer running MPLAB X IDE. 

Jumpers

SD Memory Cards

  • Ensure no SD memory cards are plugged into the SD card (J4) connector.

Power

Debug Communications

  • The SAMA7G54-EK contains a J-Link On-Board Debug Probe. Connect a micro-B USB cable to J24 and the host computer running MPLAB X IDE.

Console Serial Communications

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Configure and Build a Project for Debugging

In this section, you will download, configure, and build a CSP Application example using MPLAB X IDE to run on the SAMA7G54-EK in debug mode. This scenario is typical of the initial project development steps of coding, building, and debugging. 

​As of MPLAB X IDE v6.05, the plugins, MPLAB Harmony v3 Content Manager (MHCM) and Configurator (MHC), have been migrated to MPLAB Code Configurator (MCC)

Normally, the MPLAB Harmony v3 Software Framework libraries are downloaded when a new MCC project is created in MPLAB X IDE. However, when working with an example application, such as this one, the MPLAB Harmony v3 Software Framework libraries are assumed preinstalled on the host computer. Therefore, if you do not have the MPLAB Harmony v3 Software Framework libraries preloaded, you will have to download or clone the CSP Application Library from the Microchip MPLAB Harmony v3 GitHub repository before opening the example application project. We will show you how in the following steps.

Download CSP Application Library.

Create a Harmony3 directory.

Create a directory named Harmony3. For a Windows® operating system, it is typically located at C:\Users\<user>\Harmony3\.

Download or clone csp_apps_sam_a7g5.

Download or clone csp_apps_sam_a7g5 library from the Microchip MPLAB Harmony 3 GitHub repository to the Harmony3 directory.


Open project pio_led_on_off_interrupt_sam_a7g5_ek.

From MPLAB X IDE, select File > Open project.

An Open Project window will open.

Locate the following project in the Harmony3 directory:

C:\Users\<user>\Harmony3\csp_apps_sam_a7g5\apps\pio\pio_led_on_off_interrupt\firmware\sam_a7g5_ek.X.

Click on the Open Project button. The pio_led_on_off_interrupt_sam_a7g5_ek project loads into MPLAB X IDE.

Open Project

​You may receive a Configuration Loading Error. This is due to an older version of the Device Family Pack (DFP) at the time of creating the at91bootstrap project. You can update the DFP to the latest version in the next steps


Configure Project Properties for Debugging in MPLAB X IDE.

Open Project Properties.

Open the pio_led_on_off_interrupt_sam_a7g5_ek Project Properties using one of the following methods:

  1. In the Projects pane, highlight pio_led_on_off_interrupt_sam_a7g5_ek and click on the wrench icon in the pio_led_on_off_interrupt_sam_a7g5_ek - Dashboard.
  2. In the Projects pane, right-click on pio_led_on_off_interrupt_sam_a7g5_ek and select Properties from the menu.

The Projects Properties – pio_led_on_off_interrupt_sam_a7g5_ek dialog box opens.

​If you received a Configuration Loading Error in the previous step, you will see a [Resolve] link next to the version of the DFP that the project was originally developed with (see the accompanying figure). To update to the latest version, highlight the latest DFP and click on the Apply button. This will update the configuration to the latest DFP.

Project Properties window

In the Categories pane, select Conf: [sam_a7g5_ek].

Select the version of DFP and XC32 Compiler you require for the application.

​The Device Family Pack (DFP) contains device-specific support software. The 32-bit MCU and MPU DFPs are maintained by Microchip Technology and are available on GitHub.

In the Connected Hardware Tool drop-down menu, select the J-Link On-Board (OB) debug probe.

​You must have the host computer running MPLAB X IDE connected to the J24 of the SAMA7G54-EK to see the J-Link OB available in the drop-down menu.

Project Config: JLink

In the Categories pane, select Bootstrap.

Observe that Use bootstrap is selected and the pre-compiled version of the at91bootstrap.elf is selected.

​While in Debug mode, the second-stage bootloader, at91bootstrap, is used by MPLAB X IDE to initialize DRAM so that it can continue loading the MPLAB Harmony 3 project binary (harmony.bin). Once the project has been loaded onto the SAMA7G54-EK, MPLAB X IDE can be used to run and debug the application.

​at91bootstrap is a second-stage bootloader for Microchip Technology Arm-based microprocessors (MPU). For more information see the "at91bootstrap: A Second Stage Bootloader for Microchip MPUspage.

Project Properties window bootstrap configuration

Click the Apply and OK buttons.

Configure the Harmony Content Path.

In this step, you will let MPLAB X IDE know the location (directory) of the Harmony v3 Software Framework on your host computer.

From the MPLAB X IDE menu, select Tools > Options.
From the Options window, select Plugins from the ribbon.
Click on the MPLAB Code Configurator 5.x tab.
Under Harmony Content Path, click on the finder and select the location of the Harmony3 directory.

Click on the Apply and OK buttons.

Options window Plugins tab


Set Debug Reset and Startup Options

In MPLAB X IDE, click on Tools > Options.

An Options window opens.

Click on the Embedded icon at the top and the Generic Settings tab.

Configure the settings for:

  • Debug Reset @ – Main
  • Debug startup – Halt at Main

Options window Embedded tab

Click on the OK button.

Power the SAMA7G54-EK 

Power the SAMA7G54-EK by using one of the following two methods: 

  • Connect a USB Micro-B cable to USB-A Port (J7) and host computer, or 
  • +5 VDC external power applied to connector J1. 

For more information see the "Power Options" section in the "SAMA7G54-EK – Features" training topic.

Press the nSTART push button (SW3). 

Pressing the nSTART push button (SW3) will turn on (wakeup) the MPU.  

On the SAMA7G54-EK, MPU startup is managed by Power Management Integrated Circuit U1 (MCP16502). The MCP16502 features a low no-load operational quiescent current and draws less than 10 μA in full shutdown. 

The SAMA7G54-EK can be configured to automatically startup when power is applied by mounting a capacitor to C240. For more information see the "SAMA7G540EK User’s Guide (DS50003273)"

At this point, you have configured the MPLAB Harmony 3 project within MPLAB X IDE. In the next section, you will build the project for debugging. 


Build the Project.

Click on the Debug Project icon on the toolbar.

The project will build with debugging parameters, load the application binary to the SAMA7G54-EK, and Halt at Main. Once the build is complete and the application binary is loaded into the target, the toolbar expands to show additional debugging icons.

​MPLAB X IDE uses at91bootstrap to initialize the SAMA7G54 and then exits without loading any additional binary files to SDRAM. MPLAB X IDE then loads the application program to SDRAM. For more information see the "SAMA7G5 Series Boot Process" training topic.

MPLAB X IDE window Debug: Halt

You can view the second-stage bootloader (at91bootstrap) activity on the console. 

For more information on establishing serial communications with the target console see the "SAMA7G54-EK – Console Serial Communications" page.

Tera Term Console

Click on the Continue button. The application binary runs within the target.

Press the USER BUTTON (SW1) and observe the RGB LED (D7) lights blue. Release the USER BUTTON and the RGB LED will turn off.

The application uses the PIO Peripheral library to generate a callback on switch press and release and drives the GPIO pin connected to the RGB LED to indicate the switch status.

 If you Stop a debug session you must press the Reset button on the SAMA7G54-EK to initiate the boot process before launching another debug session. 

Congratulations! You successfully downloaded, configured, and built an MPLAB Harmony v3 CSP Application example to run on the SAMA7G54-EK in debug mode.

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Continuing Development with MPLAB Harmony v3 Software Framework

With the project in Debug mode, you can now pause, insert additional breakpoints, and continue running the project. If you change the source code, you will need to reset the SAMA7G54-EK prior to (re)building and loading the project to the target. Resetting places the MPU back into the bootloader mode. 

For this example application, you only downloaded or cloned one MPLAB Harmony v3 library: CSP Applications for the SAMA7G54. There are several libraries required to perform full development. In this section, you will use MPLAB Code Configurator to download and manage these libraries. 

Open MPLAB Code Configurator (MCC)

Open MCC by clicking on the MCC shield on the toolbar.

The MCC Content Manager Wizard will open. In the top half window is the Required Content.

Content Manager Wizard


Expand the rows in the Component column to view the required libraries.

Click on the Finish button at the top. The required content will download. Be patient, this will take a while.

A Package Versions Used vs Available dialog may appear if the MPLAB Harmony package versions that the project was developed with do not match the versions available locally. In the next steps, you will update the project to the latest package versions.

MCC Project Manifest

Click on the Continue button.

MCC is now available. The Project Graph, Project Resources, and Device Resources windows are active.


If you received a Package Versions Used vs Available dialog, perform the following steps:

In the Device Resources pane, click on the Content Manager button.

MCC Project Graph

Observe the packages and versions that were called out in the dialog in Step 3.1 above. You can either: 

  • Individually select the latest version available for each package and click on the Apply button. In this example, the csp and dev_packs, or 
  • Click on the Select Latest Version(s) button and click on the Apply button. This will update all selected libraries to the latest version. 

MCC Content Manager

Click on the Generate button.

MCC will generate new source code.

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Download Packages for MPU Development

There are additional libraries required for MPU development. They are the Board Support Package (bsp) and Core (core).

  • The Board Support Package (bsp) contains the defines (names and attributes) of the features (clock configuration, pins, switches, and LEDs) of a selected evaluation kit.
  • The Core Package (core) contains the device driver, system service, OSAL, and third-party software libraries.
Click on the Component drop-down box and un-check Device Supported Content Only to display all available MPLAB Harmony v3 libraries.

Expand Harmony 3 - Core.

Select the latest version of the bsp and core libraries.

Click on the Apply button.

The package versions will be downloaded and installed. MCC will restart.

The bsp and core libraries give you more resources for MPU development. However, there are a number of additional libraries available. Select and download them as needed using the same steps outlined above.


Click on the Generate button. 

MCC will generate new source code. 


Close MCC.

At this point, the required libraries for the pio_led_on_off_interrupt_sam_a7g5_ek project are loaded. 

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Configure and Build a Project for Production

Once a project has been fully developed, the application is cleaned and built for production. The application binary (harmony.bin) is loaded from NVM, such as SD memory card, eMMC, NAND, and NOR Flash memories, by the second-stage bootloader: at91bootstrap.

With csp_apps_sam_a7g5 version 3.1.0, the following command needs to be added to the project properties: 

Open Project Properties.

Select Building from the Categories pane.

Check the box next to Execute this line after build.

Insert the following command in the text box below: 

${MP_CC_DIR}/xc32-objcopy -O binary ${DISTDIR}/${PROJECTNAME}.${IMAGE_TYPE}.elf ${DISTDIR}/harmony.bin 


Click on the OK button.

Project Properties: Execute after build

Clean and Build the Project

Click on the Clean and Build icon on the toolbar.

Observe the location of the production binary. Take note of this location as it contains the harmony.bin binary that you will write into NVM.

C:/Users/<user>/Harmony3/csp_apps_sam_a7g5/apps/pio/pio_on_off_interrupt/firmware/sam_a7g5_ek.X/dist/sam_a7g5_ek/production/harmony.bin 

Output pane Build Successful for a Project


Observe the DDRAM Address that harmony.bin is to be loaded by at91bootstrap. This is found in the Linker Files, ddram.ld. Take note of this value as it is required for configuring at91bootstrap to load harmony.bin from NVM.

Linker for Production: ddram

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Summary

In this training topic, you downloaded, configured, and built an MPLAB Harmony v3 application example using MPLAB X IDE to run on the SAMA7G54-EK Evaluation Kit in debug mode. You also cleaned and built the application for production and now it’s ready for writing into Non-Volatile Memory (NVM). 

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What’s Next?

Once an MPLAB Harmony v3 application (harmony.bin) has been developed and built for production, the next step is to configure and build the second-stage bootloader, at91bootstrap, for reading the harmony.bin binary from Non-Volatile Memory (NVM) and writing to SDRAM. The following training topics show how this is done for NOR Flash (QSPI), e.MMC, and SD Memory Card. 

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Learn More

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