Functions

General Description

Functions
uint8_t	SelfTests_ATOP_DAC (uint32_t adcChannel, uint32_t dacSlice, const uint32_t *dacVals, uint32_t numVals, uint16_t accuracy)
	Performs ATOP DAC R2R loopback self-test using PDL functions.

Function Documentation

SelfTests_ATOP_DAC()

uint8_t SelfTests_ATOP_DAC	(	uint32_t	adcChannel,
		uint32_t	dacSlice,
		const uint32_t *	dacVals,
		uint32_t	numVals,
		uint16_t	accuracy )

Performs ATOP DAC R2R loopback self-test using PDL functions.

This function initializes the DAC/ADC peripherals once and then tests multiple DAC values in a loop. For each value, it sets the DAC output, triggers ADC conversion, reads the result, and validates against the expected value with specified accuracy tolerance.

Parameters

adcChannel	ADC channel/group to use for measurement. Use ATOP_ADC_CHANNEL_0.
dacSlice	DAC slice to test. Use ATOP_DAC_SLICE_0 or ATOP_DAC_SLICE_1.
dacVals	Pointer to array of DAC output codes to test (0-4095 for 12-bit DAC).
numVals	Number of values in the dacVals array.
accuracy	Acceptable deviation in ADC codes. Test passes if: (dacVal - accuracy) <= adcResult <= (dacVal + accuracy)

Returns

OK_STATUS (0) - All tests passed, ADC results within tolerance
ERROR_STATUS (1) - Test failed (ADC result out of tolerance)
ERROR_BAD_PARAM (9) - Invalid parameters (bad slice, null pointer, incorrect accuracy)
MTB_STL_ERROR_TIMEOUT (10) - ADC conversion timed out

Note

The PPCA subsystem must be enabled by the caller before invoking this function (e.g. Cy_PPCA_Enable(PPCA_CNFG)). The test only configures AREF, DCSG, DAC, and ADC sub-blocks and restores their state on exit; it does not modify the top-level PPCA control register.

In loopback single-ended mode, DAC and ADC share the same voltage reference, so expected ADC result equals dacVal (1:1 code mapping).

static const uint32_t dac_test_values[] = {
    0U,      // Minimum code (0V)
    2048U,   // Mid-scale (1.65V)
    4095U    // Maximum code (3.3V)
};
#define DAC_TEST_NUM_VALUES  (sizeof(dac_test_values) / sizeof(dac_test_values[0]))
#define DAC_TEST_ACCURACY    50U
 
// Enable PPCA subsystem before calling the self-test
Cy_PPCA_Enable(PPCA_CNFG);
 
// Test DAC Slice 0
uint8_t result = SelfTests_ATOP_DAC(ATOP_ADC_CHANNEL_0, ATOP_DAC_SLICE_0,
                                     dac_test_values, DAC_TEST_NUM_VALUES,
                                     DAC_TEST_ACCURACY);
if (result != OK_STATUS)
{
    // Handle error (ERROR_STATUS or ERROR_BAD_PARAM)
}