USB Host Getting Started Application on SAM9X75 Early Access Evaluation Board

Launch MPLAB® X IDE- From the main menu, click on File, then New Project. Under Projects choose 32-bit MCC Harmony Project, click Next- For Framework Path choose the location on your PC where you want to download the Harmony 3 framework- Click Next.

Enter Location , Folder and Name of the project. Click Next.

In the Configuration Settings window, for Name enter default, for Device Family select SAM, for Target Device select SAM9X75. Click Finish.

This creates an empty project and set this project as main project. If there are other projects open in the project explorer window, set this project as main project by right clicking on the project, choose ‘Set as Main Project’.

After the project is created, MCC will be automatically launched. (To launch MCC manually, from main menu, click on Tools -> Embedded -> MPLAB® Code Configurator or click MCC button in the MPLAB® X IDE tool bar.) It will launch Content manger Wizard. Then select MPLAB® Harmony.

In addition to the required packages(csp, dev_packs), download the optional packages usb, bsp, core and then click Finish. Content download will take some time. Please wait till all the contents are downloaded.

Now a project graph will be displayed. From Device Resource add Board Support Packages for SAM9X75 Evaluation Board BSP to Project Graph.

From Device Resource, Libraries -> Host Stack , add HID Client Driver to the Project Graph. You will be prompted to allow auto-connection and auto-activation of several components- Click on Yes for all of them except “FreeRTOS”.

Choosing the HID Client Driver template automatically populates the rest of the project components. This can be seen in the way the project graph is set up and connected.

From Device Resource, Peripherals -> add DBGU to the Project Graph. This helps to print the debug messages (console serial communication messages) via comm port.

In the project graph, right click on TMR in Time and then add satisfiers TC0.

From the project graph window, click the HID Client Driver and in the Configuration Options choose Use Keyboard Driver

From the project graph window, click the USB Host Port HS Driver and in the Configuration Options enter Port Selection as 0x02(SAM9X75 Early Access Evaluation Board has two host std Type A receptacle’s, user can choose the one they want to enable(0x01 or 0x02))

Refer section 29.5 of the SAM9X75 data sheet which says “The USB device and host ports requires both the 48 MHz signal and the peripheral clock”.
Main clock= 24MHz, UPLL Clock= 24MHz*40/2 =480MHz Here UPLL Multiplier= 39 , USB Clock= 480MHz/10 = 48MHz Here USB Divider= 9.
Based on this calculations, configure the USB and peripherals clock signals as mentioned in the next step.

From the project graph window, click the system and in the Configuration Options , do the clock settings as shown below:

Ensure all the pins are configured as below:
PA26 and PA27 are for serial debugging. PC19, PC20, PC21 are for LEDs red, blue, and green respectively. PC27 and PC29 are VBUS Enable of USB.

Now Save all. Then click generate code. This will generate code for all the Device Resource that have been added in the project graph.

1. Peripheral libraries APIs can be accessed as a HTML file (*.html) from the Harmony 3 Framework path. (/framework_path/csp/docs/index.html)
2. BSP libraries APIs can be found in bsp.h
3. USB host driver APIs can be accessed as a HTML file (*.html) from the Harmony 3 Framework path. (/framework_path/usb/docs/index.html)

• bool DBGU_Write( void* buffer, const size_t size );
• bool DBGU_WriteIsBusy( void );
• bool USB_HOST_HID_KEYBOARD_EventHandlerSet(USB_HOST_HID_KEYBOARD_EVENT_HANDLER appKeyboardEventHandler);
• bool USB_HOST_BusEnable(USB_HOST_BUS bus);
• bool USB_HOST_BusIsEnabled(USB_HOST_BUS bus);
• LED_GREEN_On();

Sample code can be found here and Its header file can be found here.

Now right click on the project and click Properties. For Connected Hardware Tool -> select connected hardware debugger used, for Compiler Toolchain -> select XC32 and click Apply.

From J-32/J-Link, Option categories choose Communication and for JTAG Method, select 4-wire JTAG.

Select Bootstrap for Categories and select the Use Bootstrap checkbox. For bootstrap file -> select the at91bootstrap elf file from here- Click on Apply and OK.

By default, MPLAB X only produces ELF and Hex format output files. To generate application output in binary format, a post build step needs to be added to the project properties. To do this project properties, building, click the check box Execute this line after build, then enter the below command.

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

Clean and build the project. You should see a message on the output console that the project was successfully built. This completes the development of the usb host getting started application.

The harmony.bin binaries will be avialbale at ./firmware/sam9x75_ea.X/dist/default/production.