adc_oversampling.h File Reference

XMEGA ADC oversampling header file for ADC source code This file contains the function prototypes.

Copyright (c) 2014-2018 Microchip Technology Inc. and its subsidiaries.

Macros
#define	ASCII_BUFFER_SIZE   9
#define	NUMBER_OF_DIGITS_IN_ADCCOUNT   5
#define	NUMBER_OF_DIGITS_IN_RESULT   6

Functions
static int8_t	adc_offset_get_signed (void)
	Function to get the offset of ADC. More...
void	adc_oversampled (void)
	Function to process sampled ADC values. More...
static void	convert_to_ascii (uint8_t *buf_index, uint64_t dec_val)
	Function to convert decimal value to ASCII. More...
void	display_adccount (uint64_t adc_rawcount, uint8_t x_cordinate, uint8_t sign_flag)
	Function to display raw ADC count on LCD. More...
void	init_adc (void)
	Function to initialize the ADC. More...

Variables
volatile bool	adc_oversampled_flag
	Static variable/flag to indicate that one set of oversampling is done for start processing. More...

#define ASCII_BUFFER_SIZE   9

Referenced by adc_oversampled().

#define NUMBER_OF_DIGITS_IN_ADCCOUNT   5

Referenced by display_adccount().

#define NUMBER_OF_DIGITS_IN_RESULT   6

Referenced by convert_to_ascii().

static int8_t adc_offset_get_signed ( void  )

static

Function to get the offset of ADC.

void adc_oversampled

(

void

)

Function to process sampled ADC values.

Function to process sampled ADC values.

• Offset error compensation is applied on accumulated ADC value
• After, scaling is done with scaled factor.
• Finally, Analog value at ADC input pin is calculated
• Reset all variable used in ADC ISR and enable ADC interrupt to start next oversampling Process.

References abs, ADC_CH0, adc_ch_conf, ADC_GAIN_ERROR_FACTOR, ADC_NO_OVER_SAMP_MAX_COUNT, adc_offset, adc_offset_one_sample, ADC_OVER_SAMP_MAX_COUNT, ADC_OVER_SAMP_REF_VOLT_IN_MICRO, ADC_OVER_SAMP_SCALING_FACTOR, adc_result_accum_processed, adc_result_accumulator, adc_result_one_sample, adc_result_one_sample_processed, adc_samplecount, adcch_enable_interrupt(), ADCCH_MODE_COMPLETE, adcch_set_interrupt_mode(), adcch_write_configuration(), ASCII_BUFFER_SIZE, convert_to_ascii(), display_adccount(), gfx_mono_draw_string(), sysfont, v_input, v_input_ascii_buf, and v_input_one_sample.

Referenced by main().

static void convert_to_ascii ( uint8_t *  buf_index, uint64_t  dec_val  )

static

Function to convert decimal value to ASCII.

void display_adccount	(	uint64_t	adc_rawcount,
		uint8_t	x_cordinate,
		uint8_t	sign_flag
	)

Function to display raw ADC count on LCD.

Function to display raw ADC count on LCD.

• It will extract each digit from ADC count and convert to ASCII
• Use GFX service for displaying each character

  Parameters

  adc_rawcount	ADC raw count value to be displayed.
  x_cordinate	X-coordinate where display should end.
  sign_flag	Sign of ADC count.If negative sign_flag is set.

References gfx_mono_draw_char(), NUMBER_OF_DIGITS_IN_ADCCOUNT, and sysfont.

Referenced by adc_oversampled().

void init_adc

(

void

)

Function to initialize the ADC.

Function to initialize the ADC.

• ADCB-CH0 is configured in 12bit, signed differential mode without gain
• To read ADC offset, ADCB-Pin3(PB3) used as both +ve and -ve input
• After reading ADC offset,to start oversampling,ADCB +ve and -ve input are configured

References ADC_CH0, adc_ch_conf, adc_conf, adc_disable(), adc_enable(), adc_handler(), adc_offset, adc_offset_get_signed(), adc_offset_one_sample, ADC_OVER_SAMP_NEGATIVE_PIN, ADC_OVER_SAMP_POSTIVE_PIN, ADC_OVER_SAMPLED_NUMBER, adc_read_configuration(), ADC_REF_AREFB, ADC_RES_12, adc_set_callback(), adc_set_clock_rate(), adc_set_conversion_parameters(), adc_set_conversion_trigger(), ADC_SIGN_ON, ADC_TRIG_MANUAL, adc_write_configuration(), adcch_enable_interrupt(), ADCCH_MODE_COMPLETE, ADCCH_NEG_PIN3, ADCCH_POS_PIN3, adcch_read_configuration(), adcch_set_input(), adcch_set_interrupt_mode(), and adcch_write_configuration().

Referenced by main().

volatile bool adc_oversampled_flag

Static variable/flag to indicate that one set of oversampling is done for start processing.

Static variable/flag to indicate that one set of oversampling is done for start processing.

Referenced by adc_handler(), and main().