5.29 USBFSD Guide

This example combines HID and CDC into one device, then reports keystrokes on the HID channel and forwards serial data on the CDC channel.

Data path: projects/n32h49x_EVAL/examples/USBFSD/HID_CDC_Composite/src/main.c

1. Initialize board and USB resources. First initialize the on-board LEDs and keys, then configure the USBFS pin alternate function and the USB interrupts.

    Hardware_Board_Led_Init();
    Hardware_Board_Key_Init();
    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock, initialize the device on success, and wait for host enumeration.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

        while (bDeviceState != CONFIGURED)
        {
        }

3. Report keystrokes in the main loop. After the previous transfer completes, read KEY2 and write the two-byte HID report to the IN endpoint and set it valid.

            if(PrevXferComplete)
            {
                Sendbuffer[0] = 0x05;
                if (KEY_Press_Status_Read(LEFT_BUTTON_AND_2) == SET)
                {
                    Sendbuffer[1] = 0x01;
                }
                else
                {
                    Sendbuffer[1] = 0x00;
                }
                USB_SilWrite(EP1_IN, Sendbuffer, 2);
                SetEPTxStatus(ENDP1, EP_TX_VALID);
                PrevXferComplete = 0;
            }

Corresponding source files: src/main.c

This example implements a custom HID device: the main loop reports the key state and the endpoint callback receives the LED control commands from the host.

Data path: projects/n32h49x_EVAL/examples/USBFSD/HID_Customer/src/main.c

1. Initialize board and USB resources. First initialize the on-board LEDs and keys, then configure the USBFS pin alternate function and the USB interrupts.

    Hardware_Board_Led_Init();
    Hardware_Board_Key_Init();
    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock, initialize the device on success, and wait for host enumeration.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

        while (bDeviceState != CONFIGURED)
        {
        }

3. Report keystrokes in the main loop. After the previous transfer completes, assemble the two-byte report from the KEY2 level, write it to the IN endpoint, and set it valid.

            if(PrevXferComplete)
            {
                Sendbuffer[0] = 0x05;
                if (KEY_Press_Status_Read(LEFT_BUTTON_AND_2) == SET)
                {
                    Sendbuffer[1] = 0x01;
                }
                else
                {
                    Sendbuffer[1] = 0x00;
                }
                USB_SilWrite(EP1_IN, Sendbuffer, 2);
                SetEPTxStatus(ENDP1, EP_TX_VALID);
                PrevXferComplete = 0;
            }

Corresponding source files: src/main.c

This example turns the evaluation board into a USB HID keyboard: the main loop polls the keys for a key code and the endpoint callback handles the host keyboard LED commands.

Data path: projects/n32h49x_EVAL/examples/USBFSD/HID_Keyboard/src/main.c

1. Initialize board and USB resources. First initialize the on-board LEDs and keys, then configure the USBFS pin alternate function and the USB interrupts.

    Hardware_Board_Led_Init();
    Hardware_Board_Key_Init();
    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock, initialize the device on success, and wait for host enumeration.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

        while (bDeviceState != CONFIGURED)
        {
        }

3. Write the key report and set the endpoint valid. Once the key code is assembled, write the 8-byte report to the IN endpoint, set it valid, and clear the key code for the next report.

                USB_SilWrite(EP1_IN, key_buffer, 8);
                SetEPTxStatus(ENDP1, EP_TX_VALID);
                key_buffer[2] = 0;
                PrevXferComplete = 0;
            }

Corresponding source files: src/main.c

This example adds crystal-less mode and remote wakeup to the HID keyboard: after the host suspends, the SOF count decides whether the bus woke up.

Data path: projects/n32h49x_EVAL/examples/USBFSD/HID_Keyboard_Xtal_Less/src/main.c

1. Initialize board, key interrupt, and USB resources. First initialize the LEDs, the keys, and the key interrupt, then configure the USBFS pin alternate function and the USB interrupts.

    Hardware_Board_Led_Init();
    Hardware_Board_Key_Init();
    Cfg_KeyInterrupt();
    Set_System();
    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Select the system clock and start the device. Take 240MHz when the crystal-less macro is not defined and the core clock when it is, then configure and start the USB device.

#ifndef USE_USBFSD_XTALLESS
#if defined (N32H49X)
    system_clock = SYSCLK_VALUE_240MHz;
#endif
#else
    system_clock = SystemCoreClock;
#endif /* USE_USBFSD_XTALLESS */

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

        while (bDeviceState != CONFIGURED)
        {
        }

3. Decide on wakeup after suspend. Record the current SOF count, wait for a while, and if the count changed the bus is still active, so restore the configured state.

            if (bDeviceState == SUSPENDED)
            {
                LastIntPackSOF = bIntPackSOF;

                for (i = 0; i < 0xffff; i++);

                if (LastIntPackSOF != bIntPackSOF)
                {
                    bDeviceState = CONFIGURED;
                }
            }

Corresponding source files: src/main.c

This example combines HID and MSC into one device: the HID channel reports keystrokes and receives LED control, and the MSC channel emulates a USB drive with the SPI FLASH.

Data path: projects/n32h49x_EVAL/examples/USBFSD/HID_MSC_Composite/src/main.c

1. Initialize the storage medium, board, and USB resources. First initialize the on-board LEDs and keys, then the SPI FLASH storage medium, the USBFS pins, and the interrupts.

    Hardware_Board_Led_Init();
    Hardware_Board_Key_Init();
    MAL_Config();
    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock, initialize the device on success, and wait for host enumeration.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

        while (bDeviceState != CONFIGURED)
        {
        }

3. Report keystrokes in the main loop. After the previous transfer completes, read KEY2 and write the two-byte HID report to the IN endpoint and set it valid.

            if(PrevXferComplete)
            {
                Sendbuffer[0] = 0x05;
                if (KEY_Press_Status_Read(LEFT_BUTTON_AND_2) == SET)
                {
                    Sendbuffer[1] = 0x01;
                }
                else
                {
                    Sendbuffer[1] = 0x00;
                }
                USB_SilWrite(EP1_IN, Sendbuffer, 2);
                SetEPTxStatus(ENDP1, EP_TX_VALID);
                PrevXferComplete = 0;
            }

Corresponding source files: src/main.c

This example treats the evaluation board keys as a mouse: the main loop polls the direction state and writes a movement report to the endpoint for the interrupt to send.

Data path: projects/n32h49x_EVAL/examples/USBFSD/JoyStickMouse/src/main.c

1. Initialize board and USB resources. First initialize the on-board LEDs and keys, then configure the USBFS pin alternate function and the USB interrupts.

    Hardware_Board_Led_Init();
    Hardware_Board_Key_Init();
    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock and initialize the device on success.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();
    }

3. Send movement reports in the main loop. In the configured state, send a mouse report whenever the direction state is non-zero and the previous transfer has completed.

    while (1)
    {
        if (bDeviceState == CONFIGURED)
        {
            if ((JoyState() != 0) && (PrevXferComplete))
            {
                Joystick_Send(JoyState());
            }
        }
    }

Corresponding source files: src/main.c

This example emulates a USB drive with the on-board SPI FLASH: the main program mounts the FLASH as a storage medium, then starts the device and waits for host access.

Data path: projects/n32h49x_EVAL/examples/USBFSD/Mass_Storage/src/main.c

1. Initialize the storage medium and USB resources. First initialize the SPI FLASH storage medium, then configure the USBFS pin alternate function and the USB interrupts.

    MAL_Config();
    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock, initialize the device on success, and wait for host enumeration.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

        while (bDeviceState != CONFIGURED)
        {
        }
    }

3. Wait in an empty loop for mass-storage access. After the configured state the main loop is empty and all read and write requests are handled by the MSC callback.

    while(1)
    {
    }

Corresponding source files: src/main.c

This example combines MSC and CDC into one device: the MSC channel emulates a USB drive with the SPI FLASH and the CDC channel exchanges data with USART1.

Data path: projects/n32h49x_EVAL/examples/USBFSD/MSC_CDC_Composite/src/main.c

1. Initialize the storage medium and USB resources. First initialize the SPI FLASH storage medium, then configure the USBFS pin alternate function and the USB interrupts.

    MAL_Config();
    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock, initialize the device on success, and wait for host enumeration.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

        while (bDeviceState != CONFIGURED)
        {
        }
    }

3. Wait in an empty loop for data forwarding. After the configured state the main loop is empty and the mass-storage and serial transfers are handled by the MSC and CDC callbacks.

    while(1)
    {
    }

Corresponding source files: src/main.c

This example turns the evaluation board into a USB printer: the bulk endpoint receives the print data from the host and the main loop passes the received data back to the send flow.

Data path: projects/n32h49x_EVAL/examples/USBFSD/Printer/src/main.c

1. Initialize USB resources. Configure the USBFS pin alternate function and the USB interrupts.

    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock, initialize the device on success, and wait for host enumeration.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

        while (bDeviceState != CONFIGURED)
        {
        }
    }

3. Forward the received data in the main loop. When the receive flag is seen, clear it and call the send flow to return the last received data.

    while (1)
    {
        if (m_rx_flag)
        {
            m_rx_flag = 0;
            m_BulkData_send(m_rx_buf, m_rx_len);
        }
    }

Corresponding source files: src/main.c

This example turns the evaluation board into a USB virtual COM port: after device initialization the virtual COM port forwards data both ways with the on-board USART1.

Data path: projects/n32h49x_EVAL/examples/USBFSD/Virtual_COM_Port/src/main.c

1. Initialize USB resources. Configure the USBFS pin alternate function and the USB interrupts.

    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock, initialize the device on success, and wait for host enumeration.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

        while (bDeviceState != CONFIGURED)
        {
        }
    }

3. Wait in an empty loop for serial forwarding. After the configured state the main loop is empty and forwarding is handled entirely by the endpoint callbacks.

    while(1)
    {
    }

Corresponding source files: src/main.c

This example turns the evaluation board into a virtual COM port loopback: the main loop keeps reading the virtual COM port and echoes the received data back to the host unchanged.

Data path: projects/n32h49x_EVAL/examples/USBFSD/Virtual_COM_Port_LoopBack/src/main.c

1. Initialize USB resources. Configure the USBFS pin alternate function and the USB interrupts.

    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock and initialize the device on success.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

3. Read and echo in the main loop. In the configured state read the virtual COM port and echo the same data back once a non-zero length is received and the previous send has completed.

        while(1)
        {
            if (bDeviceState == CONFIGURED)
            {
                CDC_Receive_DATA();
                /*Check to see if we have data yet */
                if (Receive_length != 0)
                {
                    if (packet_sent == 1)
                    {
                        CDC_Send_DATA ((unsigned char*)Receive_Buffer,Receive_length);
                    }
                    Receive_length = 0;
                }
            }
        }

Corresponding source files: src/main.c

This example provides several virtual COM ports and loops each of them back: the main program initializes the flags by the port count and the main loop reads and echoes each port in turn.

Data path: projects/n32h49x_EVAL/examples/USBFSD/Virtual_COM_Port_LoopBack_Composite/src/main.c

1. Initialize USB resources. Configure the USBFS pin alternate function and the USB interrupts.

    USBFS_IO_Configure();
    USB_Interrupts_Config();

2. Configure and start the USB device. Configure USB with the 240MHz system clock and initialize the device on success.

    if(USB_Config(system_clock) == SUCCESS)
    {
        USB_Init();

3. Read and echo each port in the main loop. In the configured state read every virtual COM port in turn and then echo the received data of the matching port back unchanged.

        while(1)
        {
            if (bDeviceState == CONFIGURED)
            {
                CDC_Receive_DATA();
                /*Check to see if we have data yet */

Corresponding source files: src/main.c