AudioInput.c

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/*
 * @brief Make your board becomes a USB microphone
 *
 * @note
 * Copyright(C) NXP Semiconductors, 2012
 * Copyright(C) Dean Camera, 2011, 2012
 * All rights reserved.
 *
 * @par
 * Software that is described herein is for illustrative purposes only
 * which provides customers with programming information regarding the
 * LPC products.  This software is supplied "AS IS" without any warranties of
 * any kind, and NXP Semiconductors and its licensor disclaim any and
 * all warranties, express or implied, including all implied warranties of
 * merchantability, fitness for a particular purpose and non-infringement of
 * intellectual property rights.  NXP Semiconductors assumes no responsibility
 * or liability for the use of the software, conveys no license or rights under any
 * patent, copyright, mask work right, or any other intellectual property rights in
 * or to any products. NXP Semiconductors reserves the right to make changes
 * in the software without notification. NXP Semiconductors also makes no
 * representation or warranty that such application will be suitable for the
 * specified use without further testing or modification.
 *
 * @par
 * Permission to use, copy, modify, and distribute this software and its
 * documentation is hereby granted, under NXP Semiconductors' and its
 * licensor's relevant copyrights in the software, without fee, provided that it
 * is used in conjunction with NXP Semiconductors microcontrollers.  This
 * copyright, permission, and disclaimer notice must appear in all copies of
 * this code.
 */

#include "AudioInput.h"

/*****************************************************************************
 * Private types/enumerations/variables
 ****************************************************************************/

/*****************************************************************************
 * Public types/enumerations/variables
 ****************************************************************************/

USB_ClassInfo_Audio_Device_t Microphone_Audio_Interface = {
 .Config = {
  .StreamingInterfaceNumber = 1,

  .DataINEndpointNumber     = AUDIO_STREAM_EPNUM,
  .DataINEndpointSize       = AUDIO_STREAM_EPSIZE,
  .PortNumber             = 0,
 },
};

#define AUDIO_MAX_SAMPLE_FREQ   48000

uint32_t CurrentAudioSampleFrequency = AUDIO_MAX_SAMPLE_FREQ;
/* Sample Buffer */
// uint16_t* sample_buffer = NULL;
PRAGMA_ALIGN_4
uint16_t sample_buffer[512] ATTR_ALIGNED(4) __BSS(USBRAM_SECTION);
uint32_t sample_buffer_size = 0;

/*****************************************************************************
 * Private functions
 ****************************************************************************/

/* Configures the board hardware and chip peripherals for the demo's
   functionality. */
static void SetupHardware(void)
{
 Board_Init();
 Board_Buttons_Init();
 USB_Init(Microphone_Audio_Interface.Config.PortNumber, USB_MODE_Device);
}

/*****************************************************************************
 * Public functions
 ****************************************************************************/

void Audio_Reset_Data_Buffer(void)
{}

void Audio_Init(uint32_t samplefreq)
{
 CurrentAudioSampleFrequency = samplefreq;
 sample_buffer_size = samplefreq * sizeof(uint16_t) / 1000;
}

uint32_t CALLBACK_HAL_GetISOBufferAddress(const uint32_t EPNum, uint32_t *packet_size) {

 /* Check if this is audio stream endpoint */
 *packet_size = sample_buffer_size;
 if ((EPNum & 0x7F) == AUDIO_STREAM_EPNUM) {
  return (uint32_t) &sample_buffer[0];
 }
 else {return 0; }
}

int main(void)
{
 uint32_t Button_State = 0;
 SetupHardware();

 // sample_buffer = (uint16_t*)Audio_Get_ISO_Buffer_Address(0);
#if defined(USB_DEVICE_ROM_DRIVER)
 UsbdAdc_Init(&Microphone_Audio_Interface);
#endif

 for (;; ) {
  /* Only generate audio if the board button is being pressed */
  /* Generate Square Wave at 1kHz */
  if ((Buttons_GetStatus() & BUTTONS_BUTTON1) != Button_State) {
   int i;
   Button_State ^= BUTTONS_BUTTON1;
   for (i = 0; i < sample_buffer_size / 4; i++) {
    sample_buffer[i] = (Button_State << 15);
   }
  }
#if !defined(USB_DEVICE_ROM_DRIVER)
  Audio_Device_USBTask(&Microphone_Audio_Interface);
  USB_USBTask(Microphone_Audio_Interface.Config.PortNumber, USB_MODE_Device);
#endif
 }
}

void EVENT_USB_Device_Connect(void)
{}

void EVENT_USB_Device_Disconnect(void)
{}

void EVENT_USB_Device_ConfigurationChanged(void)
{
 bool ConfigSuccess = true;

 ConfigSuccess &= Audio_Device_ConfigureEndpoints(&Microphone_Audio_Interface);

 // LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
}

void EVENT_USB_Device_ControlRequest(void)
{
 Audio_Device_ProcessControlRequest(&Microphone_Audio_Interface);
}

bool CALLBACK_Audio_Device_GetSetEndpointProperty(USB_ClassInfo_Audio_Device_t *const AudioInterfaceInfo,
              const uint8_t EndpointProperty,
              const uint8_t EndpointAddress,
              const uint8_t EndpointControl,
              uint16_t *const DataLength,
              uint8_t *Data)
{
 /* Check the requested endpoint to see if a supported endpoint is being manipulated */
 if (EndpointAddress == (ENDPOINT_DIR_IN | Microphone_Audio_Interface.Config.DataINEndpointNumber)) {
  /* Check the requested control to see if a supported control is being manipulated */
  if (EndpointControl == AUDIO_EPCONTROL_SamplingFreq) {
   switch (EndpointProperty) {
   case AUDIO_REQ_SetCurrent:
    /* Check if we are just testing for a valid property, or actually adjusting it */
    if (DataLength != NULL) {
     /* Set the new sampling frequency to the value given by the host */
     CurrentAudioSampleFrequency =
      (((uint32_t) Data[2] << 16) | ((uint32_t) Data[1] << 8) | (uint32_t) Data[0]);
     if (CurrentAudioSampleFrequency > AUDIO_MAX_SAMPLE_FREQ) {
      return false;
     }
     sample_buffer_size = CurrentAudioSampleFrequency * sizeof(uint16_t) / 1000;
    }

    return true;

   case AUDIO_REQ_GetCurrent:
    /* Check if we are just testing for a valid property, or actually reading it */
    if (DataLength != NULL) {
     *DataLength = 3;

     Data[2] = (CurrentAudioSampleFrequency >> 16);
     Data[1] = (CurrentAudioSampleFrequency >> 8);
     Data[0] = (CurrentAudioSampleFrequency &  0xFF);
    }

    return true;
   }
  }
 }

 return false;
}

bool CALLBACK_Audio_Device_GetSetInterfaceProperty(USB_ClassInfo_Audio_Device_t *const AudioInterfaceInfo,
               const uint8_t Property,
               const uint8_t EntityAddress,
               const uint16_t Parameter,
               uint16_t *const DataLength,
               uint8_t *Data)
{
 /* No audio interface entities in the device descriptor, thus no properties to get or set. */
 return false;
}