ADCSequenceConfigure(,,,)函数理解

//*****************************************************************************
//
//! Configures the trigger source and priority of a sample sequence.
//!
//! \param ui32Base is the base address of the ADC module.
//! \param ui32SequenceNum is the sample sequence number.
//! \param ui32Trigger is the trigger source that initiates the sample
//! sequence; must be one of the \b ADC_TRIGGER_* values.
//! \param ui32Priority is the relative priority of the sample sequence with
//! respect to the other sample sequences.
//!
//! This function configures the initiation criteria for a sample sequence.
//! Valid sample sequencers range from zero to three; sequencer zero captures
//! up to eight samples, sequencers one and two capture up to four samples,
//! and sequencer three captures a single sample. The trigger condition and
//! priority (with respect to other sample sequencer execution) are set.
//!
//! The \e ui32Trigger parameter can take on the following values:
//!
//! - \b ADC_TRIGGER_PROCESSOR - A trigger generated by the processor, via the
//! ADCProcessorTrigger() function.
//! - \b ADC_TRIGGER_COMP0 - A trigger generated by the first analog
//! comparator; configured with ComparatorConfigure().
//! - \b ADC_TRIGGER_COMP1 - A trigger generated by the second analog
//! comparator; configured with ComparatorConfigure().
//! - \b ADC_TRIGGER_COMP2 - A trigger generated by the third analog
//! comparator; configured with ComparatorConfigure().
//! - \b ADC_TRIGGER_EXTERNAL - A trigger generated by an input from the Port
//! B4 pin. Note that some microcontrollers can
//! select from any GPIO using the
//! GPIOADCTriggerEnable() function.
//! - \b ADC_TRIGGER_TIMER - A trigger generated by a timer; configured with
//! TimerControlTrigger().
//! - \b ADC_TRIGGER_PWM0 - A trigger generated by the first PWM generator;
//! configured with PWMGenIntTrigEnable().
//! - \b ADC_TRIGGER_PWM1 - A trigger generated by the second PWM generator;
//! configured with PWMGenIntTrigEnable().
//! - \b ADC_TRIGGER_PWM2 - A trigger generated by the third PWM generator;
//! configured with PWMGenIntTrigEnable().
//! - \b ADC_TRIGGER_PWM3 - A trigger generated by the fourth PWM generator;
//! configured with PWMGenIntTrigEnable().
//! - \b ADC_TRIGGER_ALWAYS - A trigger that is always asserted, causing the
//! sample sequence to capture repeatedly (so long as
//! there is not a higher priority source active).
//!
//! When \b ADC_TRIGGER_PWM0, \b ADC_TRIGGER_PWM1, \b ADC_TRIGGER_PWM2 or
//! \b ADC_TRIGGER_PWM3 is specified, one of the following should be ORed into
//! \e ui32Trigger to select the PWM module from which the triggers will be
//! routed for this sequence:
//!
//! - \b ADC_TRIGGER_PWM_MOD0 - Selects PWM module 0 as the source of the
//! PWM0 to PWM3 triggers for this sequence.
//! - \b ADC_TRIGGER_PWM_MOD1 - Selects PWM module 1 as the source of the
//! PWM0 to PWM3 triggers for this sequence.
//!
//! Note that not all trigger sources are available on all Tiva family
//! members; consult the data sheet for the device in question to determine the
//! availability of triggers.
//!
//! The \e ui32Priority parameter is a value between 0 and 3, where 0
//! represents the highest priority and 3 the lowest. Note that when
//! programming the priority among a set of sample sequences, each must have
//! unique priority; it is up to the caller to guarantee the uniqueness of the
//! priorities.
//!
//! \return None.
//
//*****************************************************************************

3是系列采样的通道数，PE3这个GPIO端口号。详细见驱动库中函数说明。

不一样的，采样通道，采样序列，以及ADC0/1,这是不一样的。