Unit tests for DAC driver using ADC.

#include <stdint.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <asf.h>
#include <conf_test.h>

Macros
DAC unit test definitions
#define	NUM_AVERAGE_SAMPLES 4
	Number of samples to average over. More...

#define	NUM_CHANNELS 4
	Number of ADC channels to use. More...

#define	DAC_MIN 0
	Minimum value for DAC. More...

#define	DAC_MAX 0xfff
	Maximum value for DAC. More...

#define	DAC_8BIT_MAX 0xff
	Maximum value for DAC in 8-bit. More...

#define	ADC_ZERO 0
	ADC zero value. More...

#define	ADC_UNSIGNED_8BIT_MAX 0xff
	Maximum value for ADC in unsigned 8-bit. More...

#define	ADC_UNSIGNED_12BIT_MAX 0xfff
	Maximum value for ADC in unsigned 12-bit. More...

#define	ADC_SIGNED_12BIT_MAX 0x7ff
	Maximum value for ADC in signed 12-bit. More...

#define	ADC_SIGNED_12BIT_MIN -0x800
	Minimum value for ADC in signed 12-bit. More...

Functions
int	main (void)
	Run DAC unit tests. More...

DAC unit test helper functions
static uint16_t	left_adjust_8bit_value (uint16_t value)
	Shift 8 bit value to be used in left adjusted mode. More...

static void	single_ended_unsigned_average (ADC_t adc, uint8_t ch_mask, const uint8_t mux_inputs, uint8_t num_inputs, uint16_t *results)
	Measure single-ended input MUX combinations on channel. More...

static void	verify_unsigned_result (const struct test_case *test, uint16_t expected, uint16_t actual, uint8_t dac_ch, uint8_t adc_ch, uint8_t mux_input, uint16_t upper_limit, bool value_is_12bit)
	Verify that unsigned ADC result is in acceptable range. More...

DAC unit test functions
static void	run_dual_channel_12bit_conversion_test (const struct test_case *test)
	Test dual channel 12 bit conversion. More...

static void	run_dual_channel_8bit_conversion_test (const struct test_case *test)
	Test dual channel conversion in 8-bit mode using the DAC. More...

static void	run_single_channel_12bit_conversion_test (const struct test_case *test)
	Test single channel conversion in 12-bit mode using the DAC. More...

static void	run_single_channel_8bit_conversion_test (const struct test_case *test)
	Test single channel conversion in 8-bit mode using the DAC. More...

#define ADC_SIGNED_12BIT_MAX 0x7ff

Maximum value for ADC in signed 12-bit.

#define ADC_SIGNED_12BIT_MIN -0x800

Minimum value for ADC in signed 12-bit.

#define ADC_UNSIGNED_12BIT_MAX 0xfff

Maximum value for ADC in unsigned 12-bit.

Referenced by run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), and run_single_channel_8bit_conversion_test().

#define ADC_UNSIGNED_8BIT_MAX 0xff

Maximum value for ADC in unsigned 8-bit.

#define ADC_ZERO 0

ADC zero value.

Referenced by run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), and run_single_channel_8bit_conversion_test().

#define DAC_8BIT_MAX 0xff

Maximum value for DAC in 8-bit.

Referenced by run_dual_channel_8bit_conversion_test(), and run_single_channel_8bit_conversion_test().

#define DAC_MAX 0xfff

Maximum value for DAC.

Referenced by run_dual_channel_12bit_conversion_test(), and run_single_channel_12bit_conversion_test().

#define DAC_MIN 0

Minimum value for DAC.

Referenced by run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), and run_single_channel_12bit_conversion_test().

#define NUM_AVERAGE_SAMPLES 4

Number of samples to average over.

Referenced by single_ended_unsigned_average().

#define NUM_CHANNELS 4

Number of ADC channels to use.

Referenced by run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), and run_single_channel_8bit_conversion_test().

static uint16_t left_adjust_8bit_value ( uint16_t value )

static

Shift 8 bit value to be used in left adjusted mode.

Parameters

value value to left adjust

Returns: value left adjusted 16 bit value to write to dac_set_channel_value

Referenced by run_dual_channel_8bit_conversion_test(), and run_single_channel_8bit_conversion_test().

int main ( void )

Run DAC unit tests.

Initializes the clock system, board and serial output, then sets up the DAC unit test suite and runs it.

References usart_rs232_options::baudrate, board_init(), DEFINE_TEST_ARRAY, DEFINE_TEST_CASE, DEFINE_TEST_SUITE, run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), run_single_channel_8bit_conversion_test(), stdio_serial_init(), sysclk_init(), test_suite_run(), and usart_serial_options.

static void run_dual_channel_12bit_conversion_test ( const struct test_case * test )

static

Test dual channel 12 bit conversion.

This tests output three different values on the two DAC channels:

0 (output analog value is greater than 0, as the DAC cannot go that low)
1/2 * DAC_MAX Half of the maximum value of the DAC
DAC_MAX The maximum value (VREF) of the DAC.

These values are then measured using the ADC on the pins that are connected to the DAC channels, and the results are compared and checked to see if they are within the acceptable range of values that passes the test.

Parameters

test	Current test case.

References adc_read_configuration(), ADC_REF_BANDGAP, ADC_RES_12, adc_set_clock_rate(), adc_set_conversion_parameters(), adc_set_conversion_trigger(), ADC_SIGN_OFF, ADC_TRIG_MANUAL, ADC_UNSIGNED_12BIT_MAX, adc_write_configuration(), ADC_ZERO, DAC_ADJ_RIGHT, DAC_CH0, DAC_CH1, dac_enable(), DAC_MAX, DAC_MIN, dac_read_configuration(), DAC_REF_BANDGAP, dac_set_active_channel(), dac_set_channel_value(), dac_set_conversion_interval(), dac_set_conversion_parameters(), dac_set_conversion_trigger(), dac_set_refresh_interval(), dac_wait_for_channel_ready(), dac_write_configuration(), NUM_CHANNELS, single_ended_unsigned_average(), and verify_unsigned_result().

Referenced by main().

static void run_dual_channel_8bit_conversion_test ( const struct test_case * test )

static

Test dual channel conversion in 8-bit mode using the DAC.

This tests output three different values on the two DAC channels:

0 (output analog value is greater than 0, as the DAC cannot go that low)
1/2 * DAC_8BIT_MAX Half of the maximum value of the DAC in 8 bit mode
DAC_8BIT_MAX The maximum value (VREF) of the DAC.

These values are then measured using the ADC on the pins that are connected to the DAC channels, using all available ADC channels and the results are compared and checked to see if they are within the acceptable range of values that passes the test.

Parameters

test	Current test case.

References adc_read_configuration(), ADC_REF_BANDGAP, ADC_RES_12, adc_set_clock_rate(), adc_set_conversion_parameters(), adc_set_conversion_trigger(), ADC_SIGN_OFF, ADC_TRIG_MANUAL, ADC_UNSIGNED_12BIT_MAX, adc_write_configuration(), ADC_ZERO, DAC_8BIT_MAX, DAC_ADJ_LEFT, DAC_CH0, DAC_CH1, dac_enable(), DAC_MIN, dac_read_configuration(), DAC_REF_BANDGAP, dac_set_active_channel(), dac_set_channel_value(), dac_set_conversion_interval(), dac_set_conversion_parameters(), dac_set_conversion_trigger(), dac_set_refresh_interval(), dac_wait_for_channel_ready(), dac_write_configuration(), left_adjust_8bit_value(), NUM_CHANNELS, single_ended_unsigned_average(), and verify_unsigned_result().

Referenced by main().

static void run_single_channel_12bit_conversion_test ( const struct test_case * test )

static

Test single channel conversion in 12-bit mode using the DAC.

This tests output three different values on the two DAC channels:

0 (output analog value is greater than 0, as the DAC cannot go that low)
1/2 * DAC_MAX Half of the maximum value of the DAC
DAC_MAX The maximum value (VREF) of the DAC.

These values are then measured using the ADC on the pins that are connected to the DAC channel, using all available ADC channels and the results are compared and checked to see if they are within the acceptable range of values that passes the test.

Parameters

test	Current test case.

References adc_read_configuration(), ADC_REF_BANDGAP, ADC_RES_12, adc_set_clock_rate(), adc_set_conversion_parameters(), adc_set_conversion_trigger(), ADC_SIGN_OFF, ADC_TRIG_MANUAL, ADC_UNSIGNED_12BIT_MAX, adc_write_configuration(), ADC_ZERO, DAC_ADJ_RIGHT, DAC_CH0, dac_enable(), DAC_MAX, DAC_MIN, dac_read_configuration(), DAC_REF_BANDGAP, dac_set_active_channel(), dac_set_channel_value(), dac_set_conversion_interval(), dac_set_conversion_parameters(), dac_set_conversion_trigger(), dac_set_refresh_interval(), dac_wait_for_channel_ready(), dac_write_configuration(), NUM_CHANNELS, single_ended_unsigned_average(), and verify_unsigned_result().

Referenced by main().

static void run_single_channel_8bit_conversion_test ( const struct test_case * test )

static

Test single channel conversion in 8-bit mode using the DAC.

This tests output three different values on the two DAC channels:

0 (output analog value is greater than 0, as the DAC cannot go that low)
1/2 * DAC_8BIT_MAX Half of the maximum value of the DAC in 8 bit mode
DAC_8BIT_MAX The maximum value (VREF) of the DAC.

These values are then measured using the ADC on the pins that are connected to the DAC channel, using all available ADC channels and the results are compared and checked to see if they are within the acceptable range of values that passes the test.

Parameters

test	Current test case.

References adc_read_configuration(), ADC_REF_BANDGAP, ADC_RES_12, adc_set_clock_rate(), adc_set_conversion_parameters(), adc_set_conversion_trigger(), ADC_SIGN_OFF, ADC_TRIG_MANUAL, ADC_UNSIGNED_12BIT_MAX, adc_write_configuration(), ADC_ZERO, DAC_8BIT_MAX, DAC_ADJ_LEFT, DAC_CH0, dac_enable(), dac_read_configuration(), DAC_REF_BANDGAP, dac_set_active_channel(), dac_set_channel_value(), dac_set_conversion_interval(), dac_set_conversion_parameters(), dac_set_conversion_trigger(), dac_set_refresh_interval(), dac_wait_for_channel_ready(), dac_write_configuration(), left_adjust_8bit_value(), NUM_CHANNELS, single_ended_unsigned_average(), and verify_unsigned_result().

Referenced by main().

static void single_ended_unsigned_average	(	ADC_t *	adc,
		uint8_t	ch_mask,
		const uint8_t *	mux_inputs,
		uint8_t	num_inputs,
		uint16_t *	results
	)

static

Measure single-ended input MUX combinations on channel.

Measures a set of input MUX combinations on a single channel, using averaging of the number of samples specified with NUM_AVERAGE_SAMPLES.

Parameters

adc	Pointer to ADC to measure with.
ch_mask	Mask for channel to measure with.
mux_inputs	Pointer to array of input MUX settings.
num_inputs	Number of input MUX settings.
results	Pointer to array to store results in.

Note: The array which results points to must have at least num_inputs elements.

References adc_disable(), adc_enable(), adc_get_result, adc_start_conversion(), adc_wait_for_interrupt_flag(), adcch_disable_interrupt(), ADCCH_MODE_COMPLETE, ADCCH_NEG_NONE, adcch_set_input(), adcch_set_interrupt_mode(), adcch_write_configuration(), and NUM_AVERAGE_SAMPLES.

Referenced by run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), and run_single_channel_8bit_conversion_test().

static void verify_unsigned_result	(	const struct test_case *	test,
		uint16_t	expected,
		uint16_t	actual,
		uint8_t	dac_ch,
		uint8_t	adc_ch,
		uint8_t	mux_input,
		uint16_t	upper_limit,
		bool	value_is_12bit
	)

static

Verify that unsigned ADC result is in acceptable range.

Checks that measurement is within the expected range, and outputs a clear error message to the unit test framework if it is not.

Parameters

test	Pointer to current test case.
expected	The expected ADC result.
actual	The measured ADC result.
dac_ch	The DAC channel used.
adc_ch	The ADC channel used.
mux_input	The ADC input MUX setting used.
upper_limit	Upper limit of accepted range, can override the limit implicitly given by the accepted deviation.
value_is_12bit	Specify the resolution of the ADC result and thus the accepted deviation: `true` for +/- CONF_TEST_ACCEPT_DELTA_12BIT `false` for +/- CONF_TEST_ACCEPT_DELTA_8BIT

References test_assert_true.

Referenced by run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), and run_single_channel_8bit_conversion_test().

Microchip® Advanced Software Framework

Macros

Functions