示例#1
0
/**
 ** PDCA Init.
 **/
void init_pdca(void)
{
  // PDCA channel 0/1 options
  static const pdca_channel_options_t PDCA_CH_OPTIONS =
  {
    .addr = (void *)aDataTransfered,          // memory address
    .pid = AVR32_PDCA_PID_USART2_TX,          // select peripheral - data are transmit on USART TX line.
    .size = 0,                                // transfer counter
    .r_addr = (void *)aDataTransfered,        // next memory address
    .r_size = sizeof(aDataTransfered),        // next transfer counter
    .transfer_size = PDCA_TRANSFER_SIZE_BYTE, // select size of one data packet
    .etrig = true                          // Trigger transfer on event.
  };

  Disable_global_interrupt();

  // Initialize interrupt vectors.
  INTC_init_interrupts();

  // Register the PDCA interrupt handler to the interrupt controller.
  INTC_register_interrupt(&pdca_int_handler, PDCA_CHANNEL_IRQ, AVR32_INTC_INT0);

  Enable_global_interrupt();

  // Init PDCA channel with the pdca_options.
  pdca_init_channel(PDCA_CHANNEL_USART, &PDCA_CH_OPTIONS);
  pdca_channel = pdca_get_handler(PDCA_CHANNEL_USART); // For use in the pdca interrupt handler.

  // Enable pdca transfer error interrupt & transfer complete interrupt.
  pdca_enable_interrupt_transfer_error(PDCA_CHANNEL_USART);
  pdca_enable_interrupt_transfer_complete(PDCA_CHANNEL_USART);

  // Enable the PEVC channel "PDCA CHANNEL 0/1 ONE-ITEM-TRANSFER"
  PEVC_CHANNELS_ENABLE(ppevc, 1<<PEVC_PDCA_SOT_USER);

  // Enable the PDCA.
  pdca_enable(PDCA_CHANNEL_USART);
}

/**
 ** AST Init.
 **/
void init_ast(void)
{

  avr32_ast_pir0_t pir = {
    .insel = 14 // Set a event every second
  };

  ast_calendar_t ast_calendar;
  ast_calendar.FIELD.sec  = 30;
  ast_calendar.FIELD.min  = 45;
  ast_calendar.FIELD.hour = 12;
  ast_calendar.FIELD.day  = 7;
  ast_calendar.FIELD.month= 10;
  ast_calendar.FIELD.year = 9;

  scif_osc32_opt_t opt;
  opt.mode = SCIF_OSC_MODE_2PIN_CRYSTAL;
  opt.startup = AVR32_SCIF_OSCCTRL32_STARTUP_0_RCOSC;

  // Start OSC_32KHZ
  scif_start_osc32(&opt,true);

  // Initialize the AST
  if (!ast_init_calendar(&AVR32_AST, AST_OSC_32KHZ, AST_PSEL_32KHZ_1HZ, ast_calendar))
  {
    print_dbg("Error initializing the AST\r\n");
    while(1);
  }

  ast_set_periodic0_value(&AVR32_AST,pir);

  ast_enable_periodic0(&AVR32_AST);

  // Clear All Interrupt
  AVR32_AST.scr=0xFFFFFFFF;

  // Enable the AST
  ast_enable(&AVR32_AST);
}

/*! \brief Initializes the MCU system clocks.
*/
static void init_sys_clocks(void)
{

  /*! \name System Clock Frequencies
   */
  //! @{
  static pcl_freq_param_t pcl_freq_param =
  {
    .cpu_f        = FCPU_HZ,
    .pba_f        = FPBA_HZ,
    .osc0_f       = FOSC0,
    .osc0_startup = OSC0_STARTUP
  };
  //! @}

  // Configure system clocks.
  if (pcl_configure_clocks(&pcl_freq_param) != PASS) {
    while(1);
  }
}

/*! \brief This example show a DMA transfer to USART controlled by the AST
    periodic alarm using the PEVC.
 */
int main(void)
{
  int i;

  // Init the string with a simple recognizable pattern.
  for(i=0;i<sizeof(aDataTransfered);i++)
    aDataTransfered[i] = '0' + (i%36);

  init_sys_clocks();

  init_usart();

  gpio_clr_gpio_pin(LED0_GPIO);

  init_pevc();

  init_ast();

  init_pdca();

  while(1)
  {
    gpio_tgl_gpio_pin(LED1_GPIO);
    delay_ms(500); //Wait 500ms
  }
}
int main(void)
{
	enum sleepmgr_mode current_sleep_mode = SLEEPMGR_ACTIVE;
	uint32_t ast_counter = 0;

	/*
	 * Initialize the synchronous clock system to the default configuration
	 * set in conf_clock.h.
	 * \note All non-essential peripheral clocks are initially disabled.
	 */
	sysclk_init();

	/*
	 * Initialize the resources used by this example to the default
	 * configuration set in conf_board.h
	 */
	board_init();

	/*
	 * Turn the activity status LED on to inform the user that the device
	 * is active.
	 */
	ioport_set_pin_level(LED_ACTIVITY_STATUS_PIN, LED_STATUS_ON);

	osc_priv_enable_osc32();

	/* Enable the AST clock. */
	sysclk_enable_pba_module(SYSCLK_AST);
	/* Initialize the AST in Counter mode. */
	ast_init_counter(AST, AST_OSC_1KHZ, AST_PSEL_32KHZ_1HZ - 6,
			ast_counter);

	/*
	 * Configure the AST to wake up the CPU when the counter reaches the
	 * selected periodic0 value.
	 */
	ast_set_periodic0_value(AST,AST_PSEL_32KHZ_1HZ - 3);
	ast_enable_periodic_interrupt(AST,0);
	ast_enable_periodic_async_wakeup(AST,0);
	ast_enable_periodic0(AST);
	ast_clear_periodic_status_flag(AST,0);

	NVIC_ClearPendingIRQ(AST_PER_IRQn);
	NVIC_EnableIRQ(AST_PER_IRQn);

	/* Enable the AST. */
	ast_enable(AST);

	/* AST can wakeup the device */
	bpm_enable_wakeup_source(BPM, (1 << BPM_BKUPWEN_AST));

	// Initialize the sleep manager, lock initial mode.
	sleepmgr_init();
	sleepmgr_lock_mode(current_sleep_mode);

	while (1) {
		/*
		 * Turn the activity status LED off to inform the user that the
		 * device is in a sleep mode.
		 */
		ioport_set_pin_level(LED_ACTIVITY_STATUS_PIN, LED_STATUS_OFF);

		/*
		 * Go to sleep in the deepest allowed sleep mode (i.e. no
		 * deeper than the currently locked sleep mode).
		 */
		sleepmgr_enter_sleep();

		/*
		 * Turn the activity status LED on to inform the user that the
		 * device is active.
		 */
		ioport_set_pin_level(LED_ACTIVITY_STATUS_PIN, LED_STATUS_ON);

		/* Unlock the current sleep mode. */
		sleepmgr_unlock_mode(current_sleep_mode);

		/* Add a 3s delay. */
		delay_s(3);

		/* Lock the next sleep mode. */
		++current_sleep_mode;
		if ((current_sleep_mode >= SLEEPMGR_NR_OF_MODES)) {
			current_sleep_mode = SLEEPMGR_ACTIVE;
		}

		sleepmgr_lock_mode(current_sleep_mode);
	}
}
示例#3
0
/**
 * \brief Initializes the ADCIFB module with trigger
 * - Initialize the trigger mode & compare interrupts for ADCIFB
 *
 * \retval STATUS_OK   Configuration OK
 * \retval ERR_TIMEOUT Timeout on configuring ADCIFB module
 * \retval ERR_BUSY    ADCIFB module unable to configure the trigger
 */
static status_code_t adc_init()
{
	/* GPIO pin/adc - function map. */
	static const gpio_map_t ADCIFB_GPIO_MAP = {
		{EXAMPLE_ADCIFB_PIN, EXAMPLE_ADCIFB_FUNCTION}
	};

	/* ADCIFB Configuration */
	adcifb_opt_t adcifb_opt = {
		/* Resolution mode */
		.resolution = AVR32_ADCIFB_ACR_RES_10BIT,
		/* Channels Sample & Hold Time in [0,15] */
		.shtim  = ADC_SAMPLE_HOLD_TIME,
		/* ADC Clock Prescaler */
		.ratio_clkadcifb_clkadc = (sysclk_get_pba_hz()) / ADC_FREQUENCY,
		.startup = ADC_STARTUP_TIME,
		/* ADCIFB Sleep Mode enabled */
		.sleep_mode_enable = true
	};

	/* Disable pull up on ADCIFB channel input pin */
	gpio_disable_pin_pull_up(EXAMPLE_ADCIFB_PIN);
	/* Enable the ADC pins */
	gpio_enable_module(ADCIFB_GPIO_MAP,
			sizeof(ADCIFB_GPIO_MAP) / sizeof(ADCIFB_GPIO_MAP[0]));
	/* Enable ADCIFB clock */
	sysclk_enable_pba_module(SYSCLK_ADCIFB);
	/* Configure the ADCIFB peripheral */
	if (adcifb_configure(adcifb, &adcifb_opt)) {
		/* Error configuring the ADCIFB */
		return ERR_TIMEOUT;
	}

	/* Configure the trigger for ADCIFB peripheral */
	if (adcifb_configure_trigger(adcifb, AVR32_ADCIFB_TRGR_TRGMOD_EVT, 0)) {
		/* Error configuring the trigger for ADCIFB */
		return ERR_BUSY;
	}

	/* Enable ADCIFB Channel 0 */
	adcifb_channels_enable(adcifb, EXAMPLE_ADCIFB_CHANNEL);

	/* Disable global interrupts */
	cpu_irq_disable();

	/*
	 * Initialize the interrupt vectors
	 * Note: This function adds nothing for IAR as the interrupts are
	 * handled by the IAR compiler itself. It provides an abstraction
	 * between GCC & IAR compiler to use interrupts.
	 * Refer function implementation in interrupt_avr32.h
	 */
	irq_initialize_vectors();

	/*
	 * Register the ADCIFB interrupt handler
	 * Note: This function adds nothing for IAR as the interrupts are
	 * handled by the IAR compiler itself. It provides an abstraction
	 * between GCC & IAR compiler to use interrupts.
	 * Refer function implementation in interrupt_avr32.h
	 */
	irq_register_handler(&ADCIFB_interrupt_handler, AVR32_ADCIFB_IRQ,
			ADC_INTERRUPT_PRIORITY);

	/*
	 * Set the threshold value in CVR.LV register to generate interrupt
	 * when the value detected is above the threshold.
	 * 1.500 V with 10-bit resolution
	 */
	adcifb_set_high_compare_value(adcifb, ADC_COMPARE_VALUE);

	/* Enable the Analog Compare option in ADCIFB */
	adcifb_enable_analog_compare_mode(adcifb);

	/* Enable the data ready interrupt for ADCIFB */
	adcifb_enable_compare_gt_interrupt(adcifb);

	return STATUS_OK;
} /* End of adc_init() */

/**
 * \brief  Asynchronous Timer Initialization
 * - Start the 32KHz Oscillator
 * - Initializes the AST module with periodic trigger events
 *
 * \retval STATUS_OK      Configuration OK
 * \retval ERR_TIMEOUT    Error in configuring the AST module
 */
static status_code_t ast_init()
{
	/* Initial Count value to write in AST */
	unsigned long ast_counter = 0;
	/* Set the prescaler to set a periodic trigger from AST */
	avr32_ast_pir0_t pir = {
		.insel = AST_TRIGGER_PRESCALER
	};

	/* Set the OSC32 parameters */
	scif_osc32_opt_t osc32_opt = {
		.mode = SCIF_OSC_MODE_2PIN_CRYSTAL_HICUR,
		.startup = OSC32_STARTUP_8192,
		.pinsel = BOARD_OSC32_PINSEL,
		.en1k = false,
		.en32k = true
	};

	/* Enable the 32KHz Oscillator */
	scif_start_osc32(&osc32_opt, true);
	/* Enable the Peripheral Event System Clock */
	sysclk_enable_hsb_module(SYSCLK_EVENT);
	/* Enable PBA clock for AST clock to switch its source */
	sysclk_enable_pba_module(SYSCLK_AST);
	/* Initialize the AST in counter mode */
	if (!ast_init_counter(&AVR32_AST, AST_CLOCK_SOURCE, AST_PRESCALER,
			ast_counter)) {
		return ERR_TIMEOUT;
	}

	/* Initialize the periodic value register with the prescaler */
	ast_set_periodic0_value(&AVR32_AST, pir);
	/* Enable the AST periodic event */
	ast_enable_periodic0(&AVR32_AST);

	/* Clear All AST Interrupt request and clear SR */
	ast_clear_all_status_flags(&AVR32_AST);

	/* Enable the AST */
	ast_enable(&AVR32_AST);

	/* Disable PBA clock for AST after switching its source to OSC32 */
	sysclk_disable_pba_module(SYSCLK_AST);

	return STATUS_OK;
} /* End of ast_init() */

/**
 * \brief  Low Power Configuration
 * Initializes the power saving measures to reduce power consumption
 * - Enable pullups on GPIO pins
 * - Disable the clocks to unused modules
 * - Disable internal voltage regulator when in 1.8V supply mode
 */
static void power_save_measures_init()
{
	uint8_t i;
	uint32_t gpio_mask[AVR32_GPIO_PORT_LENGTH] = {0};

	/*
	 * Enable internal pull-ups on all unused GPIO pins
	 * Note: Pull-ups on Oscillator or JTAG pins can be enabled only if they
	 * are not used as an oscillator or JTAG pin respectively.
	 */
	for (i = 0; i < (sizeof(gpio_used_pins) / sizeof(uint32_t)); i++) {
		gpio_mask[gpio_used_pins[i] >>
		5] |= 1 << (gpio_used_pins[i] & 0x1F);
	}
	for (i = 0; i < AVR32_GPIO_PORT_LENGTH; i++) {
		gpio_configure_group(i, ~(gpio_mask[i]),
				GPIO_PULL_UP | GPIO_DIR_INPUT);
	}
	/* Disable OCD clock which is not disabled by sysclk service */
	sysclk_disable_cpu_module(SYSCLK_OCD);
#if POWER_SUPPLY_MODE_1_8V

	/*
	 * When using 1.8V Single supply mode, the Voltage Regulator can be
	 * shut-down using the code below, in-order to save power.
	 * See Voltage Regulator Calibration Register in datasheet for more
	 *info.
	 * CAUTION: When using 3.3V Single supply mode, the Voltage Regulator
	 * cannot be shut-down and the application will hang in this loop.
	 */
	uint32_t tmp = (AVR32_SCIF.vregcr);
	tmp &= (~(1 << 5 | 1 << 18));
	AVR32_SCIF.unlock = 0xAA000000 | AVR32_SCIF_VREGCR;
	AVR32_SCIF.vregcr = tmp;
	/* Wait until internal voltage regulator is disabled. */
	while ((AVR32_SCIF.vregcr & 0x00040020)) {
	}
#endif
} /* End of power_save_measures_init() */
/**
 * \brief Initializes the ACIFB module with trigger
 * - Start the GCLK for ACIFB
 * - Initialize the trigger mode & compare interrupts for ACIFB
 *
 * \retval STATUS_OK   Configuration OK
 * \retval ERR_TIMEOUT Timeout on configuring ACIFB module
 * \retval ERR_BUSY    ACIFB module unable to configure the trigger
 */
static status_code_t ac_init()
{
	/* struct genclk_config gcfg; */
	uint32_t div = sysclk_get_pba_hz() / AC_GCLK_FREQUENCY;

	scif_gc_setup(AC_GCLK_ID, AC_GCLK_SRC, AVR32_GC_DIV_CLOCK, div);

	/* Now enable the generic clock */
	scif_gc_enable(AC_GCLK_ID);

	/* GPIO pin/acifb - function map. */
	static const gpio_map_t ACIFB_GPIO_MAP = {
		{EXAMPLE_ACIFBP_PIN, EXAMPLE_ACIFBP_FUNCTION},
		{EXAMPLE_ACIFBN_PIN, EXAMPLE_ACIFBN_FUNCTION},
	};

	/* ACIFB Configuration */
	const acifb_t acifb_opt = {
		.sut = 6, /* Resolution mode */
		.actest = TESTMODE_OFF,
		.eventen = true
	};
	/* ACIFB Channel Configuration */
	const acifb_channel_t acifb_channel_opt = {
		/* Filter length */
		.filter_len = 0,
		/* Hysteresis value */
		.hysteresis_value = 0,
		/* Output event when ACOUT is zero? */
		.event_negative = false,
		/* Output event when ACOUT is one? */
		.event_positive = false,
		/* Set the positive input */
		.positive_input = PI_ACP,
		/* Set the negative input */
		.negative_input = NI_ACN,
		/* Set the comparator mode */
		.mode = MODE_EVENT_TRIGGERED,
		/* Interrupt settings */
		.interrupt_settings = IS_VINP_LT_VINN,
		/* Analog comparator channel number */
		.ac_n = EXAMPLE_ACIFB_CHANNEL
	};

	/* Enable Analog Comparator clock */
	sysclk_enable_pba_module(SYSCLK_ACIFB);
	/* Disable pullup on ACIFB channel input pins */
	gpio_disable_pin_pull_up(EXAMPLE_ACIFBP_PIN);
	gpio_disable_pin_pull_up(EXAMPLE_ACIFBN_PIN);
	/* Enable the ACIFB pins */
	gpio_enable_module(ACIFB_GPIO_MAP,
			sizeof(ACIFB_GPIO_MAP) / sizeof(ACIFB_GPIO_MAP[0]));
	/* Configure the ACIFB peripheral */
	acifb_setup_and_enable(acifb, &acifb_opt);
	/* Configure the ACIFB channel with interrupt & trigger */
	acifb_channels_setup(acifb, &acifb_channel_opt, AC_NB_CHANNELS);

	/* Disable global interrupts */
	cpu_irq_disable();

	/*
	 * Initialize the interrupt vectors
	 * Note: This function adds nothing for IAR as the interrupts are
	 * handled by the IAR compiler itself. It provides an abstraction
	 * between GCC & IAR compiler to use interrupts.
	 * Refer function implementation in interrupt_avr32.h
	 */
	irq_initialize_vectors();

	/*
	 * Register the ACIFB interrupt handler
	 * Note: This function adds nothing for IAR as the interrupts are
	 * handled by the IAR compiler itself. It provides an abstraction
	 * between GCC & IAR compiler to use interrupts.
	 * Refer function implementation in interrupt_avr32.h
	 */
	irq_register_handler(&ACIFB_interrupt_handler, AVR32_ACIFB_IRQ,
			AC_INTERRUPT_PRIORITY);
	/* Enable Analog Comparator Channel interrupt */
	acifb_enable_comparison_interrupt(acifb, EXAMPLE_ACIFB_CHANNEL);
	/* Enable global interrupts */
	cpu_irq_enable();

	return STATUS_OK;
} /* End of ac_init() */

/**
 * \brief  Asynchronous Timer Initialization
 * - Start the 32KHz Oscillator
 * - Initializes the AST module with periodic trigger events
 *
 * \retval STATUS_OK   Configuration OK
 * \retval ERR_BUSY    Error in configuring the AST module
 */
static status_code_t ast_init()
{
	/* Initial Count value to write in AST */
	unsigned long ast_counter = 0;
	/* Set the prescaler to set a periodic trigger from AST */
	avr32_ast_pir0_t pir = {
		.insel = AST_TRIGGER_PRESCALER
	};

	/* Set the OSC32 parameters */
	scif_osc32_opt_t osc32_opt = {
		.mode = SCIF_OSC_MODE_2PIN_CRYSTAL_HICUR,
		.startup = OSC32_STARTUP_8192,
		.pinsel = BOARD_OSC32_PINSEL,
		.en1k = false,
		.en32k = true
	};

	/* Enable the 32KHz Oscillator */
	scif_start_osc32(&osc32_opt, true);
	/* Enable the Peripheral Event System Clock */
	sysclk_enable_hsb_module(SYSCLK_EVENT);
	/* Enable PBA clock for AST clock to switch its source */
	sysclk_enable_pba_module(SYSCLK_AST);
	/* Initialize the AST in counter mode */
	if (!ast_init_counter(&AVR32_AST, AST_CLOCK_SOURCE, AST_PRESCALER,
			ast_counter)) {
		return ERR_BUSY;
	}

	/* Initialize the periodic value register with the prescaler */
	ast_set_periodic0_value(&AVR32_AST, pir);
	/* Enable the AST periodic event */
	ast_enable_periodic0(&AVR32_AST);

	/* Clear All AST Interrupt request and clear SR */
	ast_clear_all_status_flags(&AVR32_AST);

	/* Enable the AST */
	ast_enable(&AVR32_AST);
	
	/* Disable PBA clock for AST after switching its source to OSC32 */
	sysclk_disable_pba_module(SYSCLK_AST);

	return STATUS_OK;
} /* End of ast_init() */

/**
 * \brief  Low Power Configuration
 * Initializes the power saving measures to reduce power consumption
 * - Enable pull-ups on GPIO pins
 * - Disable the clocks to unwanted modules
 * - Disable internal voltage regulator when in 1.8V supply mode
 */
static void power_save_measures_init()
{
	uint8_t i;
	uint32_t gpio_mask[AVR32_GPIO_PORT_LENGTH] = {0};

	/*
	 * Enable internal pull-ups on all unused GPIO pins
	 * Note: Pull-ups on Oscillator or JTAG pins can be enabled only if they
	 * are not used as an oscillator or JTAG pin respectively.
	 */
	for (i = 0; i < (sizeof(gpio_used_pins) / sizeof(uint32_t)); i++) {
		gpio_mask[gpio_used_pins[i] >>
		5] |= 1 << (gpio_used_pins[i] & 0x1F);
	}
	for (i = 0; i < AVR32_GPIO_PORT_LENGTH; i++) {
		gpio_configure_group(i, ~(gpio_mask[i]),
				GPIO_PULL_UP | GPIO_DIR_INPUT);
	}
	/* Disable OCD clock which is not disabled by sysclk service */
	sysclk_disable_cpu_module(SYSCLK_OCD);
#if POWER_SUPPLY_MODE_1_8V

	/*
	 * When using 1.8V Single supply mode, the Voltage Regulator can be
	 * shut-down using the code below, in-order to save power.
	 * See Voltage Regulator Calibration Register in datasheet for more
	 *info.
	 * CAUTION: When using 3.3V Single supply mode, the Voltage Regulator
	 * cannot be shut-down and the application will hang in this loop.
	 */
	uint32_t tmp = (AVR32_SCIF.vregcr);
	tmp &= (~(1 << 5 | 1 << 18));
	AVR32_SCIF.unlock = 0xAA000000 | AVR32_SCIF_VREGCR;
	AVR32_SCIF.vregcr = tmp;
	/* Wait until internal voltage regulator is disabled. */
	while ((AVR32_SCIF.vregcr & 0x00040020)) {
	}
#endif
} /* End of power_save_measures_init() */
示例#5
0
static status_code_t ast_init()
{
	/* Initial Count value to write in AST */
	unsigned long ast_counter = 0;
	/* Set the prescaler to set a periodic trigger from AST */
	avr32_ast_pir0_t pir = {
		.insel = AST_TRIGGER_PRESCALER
	};
	/* Set the OSC32 parameters */
	scif_osc32_opt_t osc32_opt = {
#if BOARD_OSC32_IS_XTAL
		.mode = SCIF_OSC_MODE_2PIN_CRYSTAL_HICUR,
#else
		.mode = SCIF_OSC_MODE_EXT_CLK,
#endif
		.startup = OSC32_STARTUP_8192,
		.pinsel = BOARD_OSC32_PINSEL,
		.en1k = false,
		.en32k = true
	};

	/* Enable the 32KHz Oscillator */
	scif_start_osc32(&osc32_opt, true);
	/* Enable the Peripheral Event System Clock */
	sysclk_enable_hsb_module(SYSCLK_EVENT);
	/* Enable PBA clock for AST clock to switch its source */
	sysclk_enable_pba_module(SYSCLK_AST);
	/* Initialize the AST in counter mode */
	if (!ast_init_counter(&AVR32_AST, AST_CLOCK_SOURCE, AST_PRESCALER,
			ast_counter)) {
		return ERR_BUSY;        /* Check AST timer */
	}

	/* Initialize the periodic value register with the prescaler */
	ast_set_periodic0_value(&AVR32_AST, pir);
	/* Enable the AST periodic event */
	ast_enable_periodic0(&AVR32_AST);

	/* Clear All AST Interrupt request and clear SR */
	ast_clear_all_status_flags(&AVR32_AST);

	/* Enable the AST */
	ast_enable(&AVR32_AST);

	/* Disable PBA clock for AST after switching its source to OSC32 */
	sysclk_disable_pba_module(SYSCLK_AST);

	return STATUS_OK;
} /* End of ast_init() */

#endif

/**
 * \brief  Low Power Configuration
 * Initializes the power saving measures to reduce power consumption
 * - Enable pull ups on GPIO pins
 * - Disable the clocks to unwanted modules
 * - Disable internal voltage regulator when in 1.8V supply mode
 */
void power_save_measures_init()
{
	uint8_t i;
	uint32_t gpio_mask[AVR32_GPIO_PORT_LENGTH] = {0};

	/*
	 * Enable internal pull-ups on all unused GPIO pins
	 * Note: Pull-ups on Oscillator or JTAG pins can be enabled only if they
	 * are not used as an oscillator or JTAG pin respectively.
	 */
	for (i = 0; i < (sizeof(gpio_used_pins) / sizeof(uint32_t)); i++) {
		gpio_mask[gpio_used_pins[i] >>
		5] |= 1 << (gpio_used_pins[i] & 0x1F);
	}
	for (i = 0; i < AVR32_GPIO_PORT_LENGTH; i++) {
		gpio_configure_group(i, gpio_mask[i],
				GPIO_PULL_UP | GPIO_DIR_INPUT);
	}
	/* Disable OCD clock which is not disabled by sysclk service */
	sysclk_disable_cpu_module(SYSCLK_OCD);
#if POWER_SUPPLY_MODE_1_8V

	/*
	 * When using 1.8V Single supply mode, the Voltage Regulator can be
	 * shut-down using the code below, in-order to save power.
	 * See Voltage Regulator Calibration Register in datasheet for more
	 *info.
	 * CAUTION: When using 3.3V Single supply mode, the Voltage Regulator
	 * cannot be shut-down and the application will hang in this loop.
	 */
	uint32_t tmp = (AVR32_SCIF.vregcr);
	tmp &= (~(1 << 5));
	AVR32_SCIF.unlock = 0xAA000000 | AVR32_SCIF_VREGCR;
	AVR32_SCIF.vregcr = tmp;
	/* Wait until internal voltage regulator is disabled. */
	while ((AVR32_SCIF.vregcr & 0x20)) {
	}
#endif
} /* End of power_save_measures_init() */