sinewave_example.c File Reference

DAC Sinewave Example.

Copyright (c) 2011-2018 Microchip Technology Inc. and its subsidiaries.

#include "asf.h"
#include "conf_board.h"
#include "conf_clock.h"
#include "conf_dacc_sinewave_example.h"

Macros
#define	DACC_ANALOG_CONTROL
	Analog control value. More...
#define	DEFAULT_FREQUENCY   1000
	Default frequency. More...
#define	MAX_AMPLITUDE   (DACC_MAX_DATA)
	The maximal (peak-peak) amplitude value. More...
#define	MAX_DIGITAL   (0x7ff)
	The maximal sine wave sample data (no sign) More...
#define	MAX_FREQUENCY   3000
	Max frequency. More...
#define	MIN_AMPLITUDE   (100)
	The minimal (peak-peak) amplitude value. More...
#define	MIN_FREQUENCY   200
	Min frequency. More...
#define	SAMPLES   (100)
	SAMPLES per cycle. More...
#define	STRING_EOL   "\r"
#define	STRING_HEADER
#define	VAL_INVALID   0xFFFFFFFF
	Invalid value. More...
#define	wave_to_dacc(wave, amplitude, max_digital, max_amplitude)   (((int)(wave) * (amplitude) / (max_digital)) + (max_amplitude / 2))

Functions
static void	configure_console (void)
	Configure console. More...
static void	display_menu (void)
	Display main menu. More...
static uint32_t	get_input_value (uint32_t ul_lower_limit, uint32_t ul_upper_limit)
	Get input from user, and the biggest 4-digit decimal number is allowed. More...
int	main (void)
	DAC Sinewave application entry point. More...
void	SysTick_Handler (void)
	SysTick IRQ handler. More...

Variables
int32_t	g_l_amplitude = 0
	Amplitude. More...
uint8_t	g_uc_wave_sel = 0
	Waveform selector. More...
uint32_t	g_ul_frequency = 0
	Frequency. More...
uint32_t	g_ul_index_sample = 0
	Current g_ul_index_sample. More...
const int16_t	gc_us_sine_data [SAMPLES]
	100 points of sinewave samples, amplitude is MAX_DIGITAL*2 More...

#define DACC_ANALOG_CONTROL

Value:

(DACC_ACR_IBCTLCH0(0x02) \
        | DACC_ACR_IBCTLCH1(0x02) \
        | DACC_ACR_IBCTLDACCORE(0x01))

Analog control value.

Referenced by main().

#define DEFAULT_FREQUENCY   1000

Default frequency.

Referenced by main().

#define MAX_AMPLITUDE   (DACC_MAX_DATA)

The maximal (peak-peak) amplitude value.

Referenced by display_menu(), main(), and SysTick_Handler().

#define MAX_DIGITAL   (0x7ff)

The maximal sine wave sample data (no sign)

Referenced by SysTick_Handler().

#define MAX_FREQUENCY   3000

Max frequency.

Referenced by display_menu(), and main().

#define MIN_AMPLITUDE   (100)

The minimal (peak-peak) amplitude value.

Referenced by display_menu(), and main().

#define MIN_FREQUENCY   200

Min frequency.

Referenced by display_menu(), and main().

#define SAMPLES   (100)

SAMPLES per cycle.

Referenced by main(), and SysTick_Handler().

#define STRING_EOL   "\r"

#define STRING_HEADER

Value:

"-- DAC Sinewave Example --\r\n" \
        "-- "BOARD_NAME" --\r\n" \
        "-- Compiled: "__DATE__" "__TIME__" --"STRING_EOL

Referenced by main().

#define VAL_INVALID   0xFFFFFFFF

Invalid value.

Referenced by get_input_value(), and main().

#define wave_to_dacc	(		wave,
			amplitude,
			max_digital,
			max_amplitude
	)		(((int)(wave) * (amplitude) / (max_digital)) + (max_amplitude / 2))

Convert wave data to DACC value Put the sinewave to an offset of max_amplitude/2.

Parameters

wave	Waveform data
amplitude	Amplitude value
max_digital	Maximal digital value of input data (no sign)
max_amplitude	Maximal amplitude value

Referenced by SysTick_Handler().

static void configure_console ( void  )

static

Configure console.

References uart_rs232_options::baudrate, stdio_serial_init(), and sysclk_enable_peripheral_clock().

Referenced by main().

static void display_menu ( void  )

static

Display main menu.

References g_l_amplitude, g_uc_wave_sel, g_ul_frequency, MAX_AMPLITUDE, MAX_FREQUENCY, MIN_AMPLITUDE, and MIN_FREQUENCY.

Referenced by main().

static uint32_t get_input_value ( uint32_t  ul_lower_limit, uint32_t  ul_upper_limit  )

static

Get input from user, and the biggest 4-digit decimal number is allowed.

Parameters

ul_lower_limit	The lower limit of input
ul_upper_limit	The upper limit of input

References length, usart_serial_getchar(), and VAL_INVALID.

Referenced by main().

int main

(

void

)

DAC Sinewave application entry point.

Returns

Unused (ANSI-C compatibility).

References board_init(), configure_console(), DACC_ANALOG_CONTROL, dacc_enable(), dacc_enable_channel(), dacc_reset(), dacc_set_analog_control(), dacc_set_channel_selection(), dacc_set_power_save(), dacc_set_timing(), dacc_set_transfer_mode(), DEFAULT_FREQUENCY, display_menu(), g_l_amplitude, g_uc_wave_sel, g_ul_frequency, get_input_value(), MAX_AMPLITUDE, MAX_FREQUENCY, MIN_AMPLITUDE, MIN_FREQUENCY, SAMPLES, STRING_HEADER, sysclk_enable_peripheral_clock(), sysclk_get_cpu_hz(), sysclk_init(), usart_serial_getchar(), and VAL_INVALID.

void SysTick_Handler

(

void

)

SysTick IRQ handler.

References dacc_get_interrupt_status(), dacc_write_conversion_data(), g_l_amplitude, g_uc_wave_sel, g_ul_index_sample, gc_us_sine_data, MAX_AMPLITUDE, MAX_DIGITAL, SAMPLES, status, and wave_to_dacc.

int32_t g_l_amplitude = 0

Amplitude.

Referenced by display_menu(), main(), and SysTick_Handler().

uint8_t g_uc_wave_sel = 0

Waveform selector.

Referenced by display_menu(), main(), and SysTick_Handler().

uint32_t g_ul_frequency = 0

Frequency.

Referenced by display_menu(), and main().

uint32_t g_ul_index_sample = 0

Current g_ul_index_sample.

Referenced by SysTick_Handler().

const int16_t gc_us_sine_data[SAMPLES]

Initial value:

= {
    0x0,   0x080, 0x100, 0x17f, 0x1fd, 0x278, 0x2f1, 0x367, 0x3da, 0x449,
    0x4b3, 0x519, 0x579, 0x5d4, 0x629, 0x678, 0x6c0, 0x702, 0x73c, 0x76f,
    0x79b, 0x7bf, 0x7db, 0x7ef, 0x7fb, 0x7ff, 0x7fb, 0x7ef, 0x7db, 0x7bf,
    0x79b, 0x76f, 0x73c, 0x702, 0x6c0, 0x678, 0x629, 0x5d4, 0x579, 0x519,
    0x4b3, 0x449, 0x3da, 0x367, 0x2f1, 0x278, 0x1fd, 0x17f, 0x100, 0x080,

    -0x0,   -0x080, -0x100, -0x17f, -0x1fd, -0x278, -0x2f1, -0x367, -0x3da, -0x449,
    -0x4b3, -0x519, -0x579, -0x5d4, -0x629, -0x678, -0x6c0, -0x702, -0x73c, -0x76f,
    -0x79b, -0x7bf, -0x7db, -0x7ef, -0x7fb, -0x7ff, -0x7fb, -0x7ef, -0x7db, -0x7bf,
    -0x79b, -0x76f, -0x73c, -0x702, -0x6c0, -0x678, -0x629, -0x5d4, -0x579, -0x519,
    -0x4b3, -0x449, -0x3da, -0x367, -0x2f1, -0x278, -0x1fd, -0x17f, -0x100, -0x080
}

100 points of sinewave samples, amplitude is MAX_DIGITAL*2

Referenced by SysTick_Handler().