Texas Instruments Tiva TM4C123GH6PM, User Manual

Page: 35 / 352

Analog to Digital Converter (ADC)
5 Analog to Digital Converter (ADC)
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
5.1 Introduction
The analog to digital converter (ADC) API provides a set of functions for dealing with the ADC.
Functions are provided to configure the sample sequencers, read the captured data, register a
sample sequence interrupt handler, and handle interrupt masking/clearing.
The ADC supports twelve input channels plus an internal temperature sensor. Four sampling se-
quences, each with configurable trigger events, can be captured. The first sequence will capture up
to eight samples, the second and third sequences will capture up to four samples, and the fourth
sequence will capture a single sample. Each sample can be the same channel, different channels,
or any combination in any order.
The sample sequences have configurable priorities that determine the order in which they are cap-
tured when multiple triggers occur simultaneously. The highest priority sequence that is currently
triggered will be sampled. Care must be taken with triggers that occur frequently (such as the
“always” trigger); if their priority is too high it is possible to starve the lower priority sequences.
Hardware oversampling of the ADC data is available for improved accuracy. An oversampling fac-
tor of 2x, 4x, 8x, 16x, 32x, and 64x is supported, but reduces the throughput of the ADC by a
corresponding factor. Hardware oversampling is applied uniformly across all sample sequences.
5.2 Functions
Functions
void ROM_ADCComparatorConfigure (uint32_t ui32Base, uint32_t ui32Comp, uint32_t
ui32Config)
void ROM_ADCComparatorIntClear (uint32_t ui32Base, uint32_t ui32Status)
void ROM_ADCComparatorIntDisable (uint32_t ui32Base, uint32_t ui32SequenceNum)
void ROM_ADCComparatorIntEnable (uint32_t ui32Base, uint32_t ui32SequenceNum)
uint32_t ROM_ADCComparatorIntStatus (uint32_t ui32Base)
void ROM_ADCComparatorRegionSet (uint32_t ui32Base, uint32_t ui32Comp, uint32_t
ui32LowRef, uint32_t ui32HighRef)
void ROM_ADCComparatorReset (uint32_t ui32Base, uint32_t ui32Comp, bool bTrigger, bool
bInterrupt)
void ROM_ADCHardwareOversampleConfigure (uint32_t ui32Base, uint32_t ui32Factor)
void ROM_ADCIntClear (uint32_t ui32Base, uint32_t ui32SequenceNum)
void ROM_ADCIntDisable (uint32_t ui32Base, uint32_t ui32SequenceNum)
void ROM_ADCIntEnable (uint32_t ui32Base, uint32_t ui32SequenceNum)
uint32_t ROM_ADCIntStatus (uint32_t ui32Base, uint32_t ui32SequenceNum, bool bMasked)
uint32_t ROM_ADCPhaseDelayGet (uint32_t ui32Base)
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