This is a general-purpose ADC with up to 14 input channels. The ADC contains an internal 1.2V reference, but can also be used with external reference or full scale range equal to VDD. It can be operated in a single step mode with sampling under software control, or a continuous conversion mode with a programmable sampling rate.

This module contains setup functions for configuring the ADC; operation functions for starting the ADC and reading a sampled value; and status functions for checking if the ADC is busy or ready, or has overflowed.

Defines
#define	ADC_STARTUP_CNT 1;
#define	HAL_INP_AIN0 0x00
#define	HAL_INP_AIN1 0x01
#define	HAL_INP_AIN2 0x02
#define	HAL_INP_AIN3 0x03
#define	HAL_INP_AIN4 0x04
#define	HAL_INP_AIN5 0x05
#define	HAL_INP_AIN6 0x06
#define	HAL_INP_AIN7 0x07
#define	HAL_INP_AIN8 0x08
#define	HAL_INP_AIN9 0x09
#define	HAL_INP_AIN10 0x0A
#define	HAL_INP_AIN11 0x0B
#define	HAL_INP_AIN12 0x0C
#define	HAL_INP_AIN13 0x0D
#define	HAL_INP_VDD1_3 0x0E
#define	HAL_INP_VDD2_3 0x0F
Enumerations
enum	hal_adc_input_channel_t { HAL_ADC_INP_AIN0 = 0x00, HAL_ADC_INP_AIN1 = 0x01, HAL_ADC_INP_AIN2 = 0x02, HAL_ADC_INP_AIN3 = 0x03, HAL_ADC_INP_AIN4 = 0x04, HAL_ADC_INP_AIN5 = 0x05, HAL_ADC_INP_AIN6 = 0x06, HAL_ADC_INP_AIN7 = 0x07, HAL_ADC_INP_AIN8 = 0x08, HAL_ADC_INP_AIN9 = 0x09, HAL_ADC_INP_AIN10 = 0x0A, HAL_ADC_INP_AIN11 = 0x0B, HAL_ADC_INP_AIN12 = 0x0C, HAL_ADC_INP_AIN13 = 0x0D, HAL_ADC_INP_VDD1_3 = 0x0E, HAL_ADC_INP_VDD2_3 = 0x0F }
enum	hal_adc_reference_t { HAL_ADC_REF_INT = 0x00, HAL_ADC_REF_VDD = 0x01, HAL_ADC_REF_AIN3 = 0x02, HAL_ADC_REF_AIN9 = 0x03 }
enum	hal_adc_input_mode_t { HAL_ADC_SINGLE = 0x00, HAL_ADC_DIFF_AIN2 = 0x01, HAL_ADC_DIFF_AIN6 = 0x02 }
enum	hal_adc_conversion_mode_t { HAL_ADC_SINGLE_STEP = 0x00, HAL_ADC_CONTINOUS = 0x01 }
enum	hal_adc_sampling_rate_t { HAL_ADC_2KSPS = 0x00, HAL_ADC_4KSPS = 0x01, HAL_ADC_8KSPS = 0x02, HAL_ADC_16KSPS = 0x03 }
enum	hal_adc_power_down_delay_t { HAL_ADC_PDD_0US = 0x00, HAL_ADC_PDD_6US = 0x01, HAL_ADC_PDD_24US = 0x02, HAL_ADC_PDD_INF = 0x03 }
enum	hal_adc_acq_window_t { HAL_ADC_AQW_075US = 0x00, HAL_ADC_AQW_3US = 0x01, HAL_ADC_AQW_12US = 0x02, HAL_ADC_AQW_36US = 0x03 }
enum	hal_adc_resolution_t { HAL_ADC_RES_6BIT = 0x00, HAL_ADC_RES_8BIT = 0x01, HAL_ADC_RES_10BIT = 0x02, HAL_ADC_RES_12BIT = 0x03 }
enum	hal_adc_data_just_t { HAL_ADC_JUST_LEFT = 0x00, HAL_ADC_JUST_RIGHT = 0x01 }
enum	hal_adc_overflow_t { HAL_ADC_FLOW_NONE = 0x00, HAL_ADC_FLOW_OVER = 0x01, HAL_ADC_FLOW_UNDER = 0x02, HAL_ADC_FLOW_BOTH = 0x03 }
SETUP FUNCTIONS
void	hal_adc_set_input_channel (hal_adc_input_channel_t chsel)
void	hal_adc_set_reference (hal_adc_reference_t refsel)
void	hal_adc_set_input_mode (hal_adc_input_mode_t input_mode)
void	hal_adc_set_conversion_mode (hal_adc_conversion_mode_t conv_mode)
void	hal_adc_set_sampling_rate (hal_adc_sampling_rate_t rate)
void	hal_adc_set_power_down_delay (hal_adc_power_down_delay_t pdd)
void	hal_adc_set_acq_window (hal_adc_acq_window_t tacq)
void	hal_adc_set_resolution (hal_adc_resolution_t res)
void	hal_adc_set_data_just (hal_adc_data_just_t just)
OPERATION FUNCTIONS
void	hal_adc_start (void)
uint8_t	hal_adc_read_LSB (void)
uint8_t	hal_adc_read_MSB (void)
STATUS FUNCTIONS
_Bool	hal_adc_busy (void)
hal_adc_overflow_t	hal_adc_get_overflow_status (void)

Define Documentation

#define ADC_STARTUP_CNT 1;

The following example show a typical usage of the ADC:

 void main(void)
 {
   uint16_t adc_out;

   adc_init();                                         // Initialise ADC

   while(true)                                         // Endless loop
   {
     hal_adc_start();                                  // Start ADconversion
                                                     
     while(hal_adc_busy());                            // Wait for data ready
        
     adc_out = hal_adc_read_LSB();                     // Read LSB of output
     adc_out += ((uint16_t)hal_adc_read_MSB()) << 8;   // Add MSB of output
 
     // Output from ADC is now stored in adc_out

   }
 }

 // Initialize ADC: Set input channel to AIN7 and VDD as reference. Use 
 // single ended mode and single step conversion. Use 10 bits to represent
 // the analog input signal, set the output data to be right justified 

 void adc_init(void)
 {
   hal_adc_set_input_channel(HAL_ADC_INP_AIN7);                     
   hal_adc_set_reference(HAL_ADC_REF_VDD);                        
   hal_adc_set_input_mode(HAL_ADC_SINGLE);                             
   hal_adc_set_conversion_mode(HAL_ADC_SINGLE_STEP);               
   hal_adc_set_resolution(HAL_ADC_RES_10BIT);                          
   hal_adc_set_data_just(HAL_ADC_JUST_RIGHT);    
 }

Definition at line 76 of file hal_adc.h.

#define HAL_INP_AIN0 0x00

Definition at line 78 of file hal_adc.h.

#define HAL_INP_AIN1 0x01

Definition at line 79 of file hal_adc.h.

#define HAL_INP_AIN2 0x02

Definition at line 80 of file hal_adc.h.

#define HAL_INP_AIN3 0x03

Definition at line 81 of file hal_adc.h.

#define HAL_INP_AIN4 0x04

Definition at line 82 of file hal_adc.h.

#define HAL_INP_AIN5 0x05

Definition at line 83 of file hal_adc.h.

#define HAL_INP_AIN6 0x06

Definition at line 84 of file hal_adc.h.

#define HAL_INP_AIN7 0x07

Definition at line 85 of file hal_adc.h.

#define HAL_INP_AIN8 0x08

Definition at line 86 of file hal_adc.h.

#define HAL_INP_AIN9 0x09

Definition at line 87 of file hal_adc.h.

#define HAL_INP_AIN10 0x0A

Definition at line 88 of file hal_adc.h.

#define HAL_INP_AIN11 0x0B

Definition at line 89 of file hal_adc.h.

#define HAL_INP_AIN12 0x0C

Definition at line 90 of file hal_adc.h.

#define HAL_INP_AIN13 0x0D

Definition at line 91 of file hal_adc.h.

#define HAL_INP_VDD1_3 0x0E

Definition at line 92 of file hal_adc.h.

#define HAL_INP_VDD2_3 0x0F

Definition at line 93 of file hal_adc.h.

Enumeration Type Documentation

enum hal_adc_input_channel_t

An enum describing the ADC's input channel.

Enumerator:

HAL_ADC_INP_AIN0
HAL_ADC_INP_AIN1
HAL_ADC_INP_AIN2
HAL_ADC_INP_AIN3
HAL_ADC_INP_AIN4
HAL_ADC_INP_AIN5
HAL_ADC_INP_AIN6
HAL_ADC_INP_AIN7
HAL_ADC_INP_AIN8
HAL_ADC_INP_AIN9
HAL_ADC_INP_AIN10
HAL_ADC_INP_AIN11
HAL_ADC_INP_AIN12
HAL_ADC_INP_AIN13
HAL_ADC_INP_VDD1_3
HAL_ADC_INP_VDD2_3

Definition at line 98 of file hal_adc.h.

             {
  HAL_ADC_INP_AIN0   = HAL_INP_AIN0,
  HAL_ADC_INP_AIN1   = HAL_INP_AIN1,
  HAL_ADC_INP_AIN2   = HAL_INP_AIN2,
  HAL_ADC_INP_AIN3   = HAL_INP_AIN3,
  HAL_ADC_INP_AIN4   = HAL_INP_AIN4,
  HAL_ADC_INP_AIN5   = HAL_INP_AIN5,
  HAL_ADC_INP_AIN6   = HAL_INP_AIN6,
  HAL_ADC_INP_AIN7   = HAL_INP_AIN7,
  HAL_ADC_INP_AIN8   = HAL_INP_AIN8,
  HAL_ADC_INP_AIN9   = HAL_INP_AIN9, 
  HAL_ADC_INP_AIN10  = HAL_INP_AIN10,
  HAL_ADC_INP_AIN11  = HAL_INP_AIN11,
  HAL_ADC_INP_AIN12  = HAL_INP_AIN12,
  HAL_ADC_INP_AIN13  = HAL_INP_AIN13,
  HAL_ADC_INP_VDD1_3 = HAL_INP_VDD1_3,
  HAL_ADC_INP_VDD2_3 = HAL_INP_VDD2_3
} hal_adc_input_channel_t;

enum hal_adc_reference_t

An enum describing the ADC's reference.

Enumerator:

HAL_ADC_REF_INT	Internal 1.22V reference
HAL_ADC_REF_VDD	VDD as reference
HAL_ADC_REF_AIN3	External reference on AIN3
HAL_ADC_REF_AIN9	External reference on AIN9

Definition at line 120 of file hal_adc.h.

             {
  HAL_ADC_REF_INT  = 0x00,    
  HAL_ADC_REF_VDD  = 0x01,    
  HAL_ADC_REF_AIN3 = 0x02,    
  HAL_ADC_REF_AIN9 = 0x03     
} hal_adc_reference_t;

enum hal_adc_input_mode_t

An enum describing the ADC's single ended or differential mode.

Enumerator:

HAL_ADC_SINGLE	Single ended mode
HAL_ADC_DIFF_AIN2	Differential with AIN2 as inv. input
HAL_ADC_DIFF_AIN6	Differential with AIN6 as inv. input

Definition at line 130 of file hal_adc.h.

             {
  HAL_ADC_SINGLE    = 0x00,   
  HAL_ADC_DIFF_AIN2 = 0x01,   
  HAL_ADC_DIFF_AIN6 = 0x02    
} hal_adc_input_mode_t;

enum hal_adc_conversion_mode_t

An enum describing the ADC's conversion mode.

Enumerator:

HAL_ADC_SINGLE_STEP	Single step conversion
HAL_ADC_CONTINOUS	Cont. conversion, def. sampling rate

Definition at line 139 of file hal_adc.h.

             {
  HAL_ADC_SINGLE_STEP = 0x00, 
  HAL_ADC_CONTINOUS   = 0x01  
} hal_adc_conversion_mode_t;

enum hal_adc_sampling_rate_t

An enum describing the ADC's sampling rate (Continuous conversion).

Enumerator:

HAL_ADC_2KSPS	ADC sampling rate = 2kbps
HAL_ADC_4KSPS	ADC sampling rate = 4kbps
HAL_ADC_8KSPS	ADC sampling rate = 8kbps
HAL_ADC_16KSPS	ADC sampling rate = 16kbps

Definition at line 147 of file hal_adc.h.

             {
  HAL_ADC_2KSPS  = 0x00,      
  HAL_ADC_4KSPS  = 0x01,      
  HAL_ADC_8KSPS  = 0x02,      
  HAL_ADC_16KSPS = 0x03       
} hal_adc_sampling_rate_t;

enum hal_adc_power_down_delay_t

An enum describing the ADC's power down delay (Single step conversion).

Enumerator:

HAL_ADC_PDD_0US	ADC power down delay = 0us
HAL_ADC_PDD_6US	ADC power down delay = 6us
HAL_ADC_PDD_24US	ADC power down delay = 24us
HAL_ADC_PDD_INF	ADC power down delay = infinite

Definition at line 157 of file hal_adc.h.

             {               
  HAL_ADC_PDD_0US  = 0x00,    
  HAL_ADC_PDD_6US  = 0x01,    
  HAL_ADC_PDD_24US = 0x02,    
  HAL_ADC_PDD_INF  = 0x03     
} hal_adc_power_down_delay_t;

enum hal_adc_acq_window_t

An enum describing the ADC's input acquisition window.

Enumerator:

HAL_ADC_AQW_075US	Input acquisition window = 0.75us
HAL_ADC_AQW_3US	Input acquisition window = 3us
HAL_ADC_AQW_12US	Input acquisition window = 12us
HAL_ADC_AQW_36US	Input acquisition window = 36us

Definition at line 167 of file hal_adc.h.

             {
  HAL_ADC_AQW_075US = 0x00,   
  HAL_ADC_AQW_3US   = 0x01,   
  HAL_ADC_AQW_12US  = 0x02,   
  HAL_ADC_AQW_36US  = 0x03    
} hal_adc_acq_window_t;

enum hal_adc_resolution_t

An enum describing the ADC's resolution.

Enumerator:

HAL_ADC_RES_6BIT	ADC resolution set to 6 bit
HAL_ADC_RES_8BIT	ADC resolution set to 8 bit
HAL_ADC_RES_10BIT	ADC resolution set to 10 bit
HAL_ADC_RES_12BIT	ADC resolution set to 12 bit

Definition at line 177 of file hal_adc.h.

             {
  HAL_ADC_RES_6BIT  = 0x00,   
  HAL_ADC_RES_8BIT  = 0x01,   
  HAL_ADC_RES_10BIT = 0x02,   
  HAL_ADC_RES_12BIT = 0x03    
} hal_adc_resolution_t;

enum hal_adc_data_just_t

An enum describing the position of output data.

Enumerator:

HAL_ADC_JUST_LEFT	Left justified data
HAL_ADC_JUST_RIGHT	Right justified data

Definition at line 187 of file hal_adc.h.

             {
  HAL_ADC_JUST_LEFT  = 0x00,
  HAL_ADC_JUST_RIGHT = 0x01
} hal_adc_data_just_t;

enum hal_adc_overflow_t

An enum describing the ADC's resolution.

Enumerator:

HAL_ADC_FLOW_NONE	No overflow or underflow
HAL_ADC_FLOW_OVER	Overflow
HAL_ADC_FLOW_UNDER	Underflow
HAL_ADC_FLOW_BOTH	Both overflow and underflow

Definition at line 195 of file hal_adc.h.

             {
  HAL_ADC_FLOW_NONE  = 0x00,   
  HAL_ADC_FLOW_OVER  = 0x01,   
  HAL_ADC_FLOW_UNDER = 0x02,   
  HAL_ADC_FLOW_BOTH  = 0x03    
} hal_adc_overflow_t;

Function Documentation

void hal_adc_set_input_channel ( hal_adc_input_channel_t chsel )

Function to set the input channel for the ADC. This function sets the input channel for the ADC.

Parameters:

chsel Input channel

Definition at line 26 of file hal_adc.c.

{ // Update "chsel" bits
  ADCCON1 = ((ADCCON1 & 0xC3) | (((uint8_t)(chsel) << 2) & ~0xC3));
}

void hal_adc_set_reference ( hal_adc_reference_t refsel )

Function to set the reference for ADC This function sets the reference for conversion.

Parameters:

refsel Reference

Definition at line 32 of file hal_adc.c.

{ // Update "refsel" bits
  ADCCON1 = ((ADCCON1 & 0xFC) | (((uint8_t)(refsel)) & ~0xFC));
}

void hal_adc_set_input_mode ( hal_adc_input_mode_t input_mode )

Function to set the ADC single ended or differential mode. This function sets the single ended or differential mode of the ADC.

Parameters:

input_mode Single ended or differential mode

Definition at line 38 of file hal_adc.c.

{ // Update "diffm" bits
  ADCCON2 = ((ADCCON2 & 0x3F) | ((uint8_t)(input_mode) << 6));
}

void hal_adc_set_conversion_mode ( hal_adc_conversion_mode_t conv_mode )

Function to set the ADC conversion mode. This function sets the conversion mode of the ADC conversion.

Parameters:

conv_mode The conversion mode

Definition at line 44 of file hal_adc.c.

{ // Update "cont" bit
  ADCCON2 = ((ADCCON2 & 0xDF) | (((uint8_t)(conv_mode) << 5) & ~0xDF));
}

void hal_adc_set_sampling_rate ( hal_adc_sampling_rate_t rate )

Function to set the ADC sampling rate. This function sets the sampling rate for the ADC.

Parameters:

rate	The sampling rate

Definition at line 50 of file hal_adc.c.

{ // Update "rate" bits
  ADCCON2 = ((ADCCON2 & 0xE3) | (((uint8_t)(rate) << 2) & ~0xE3));
}

void hal_adc_set_power_down_delay ( hal_adc_power_down_delay_t pdd )

Function to set the ADC power down delay. This function sets the power down delay of the ADC.

Parameters:

pdd	The power down delay

Definition at line 56 of file hal_adc.c.

{ // Update "rate" bits
  ADCCON2 = ((ADCCON2 & 0xE3) | (((uint8_t)(pdd) << 2) & ~0xE3));
}

void hal_adc_set_acq_window ( hal_adc_acq_window_t tacq )

Function to set the duration of the acquisition window for the ADC. This function sets the duration of the acquisition window.

Parameters:

tacq	Duration of the acquisition window

Definition at line 62 of file hal_adc.c.

{ // Update "tacq" bits
  ADCCON2 = ((ADCCON2 & 0xFC) | (((uint8_t)(tacq)) & ~0xFC));
}

void hal_adc_set_resolution ( hal_adc_resolution_t res )

Function to set the ADC resolution. This function sets the resolution of the ADC conversion.

Parameters:

res	The resolution of the ADC

Definition at line 68 of file hal_adc.c.

{ // Update "resol" bits
  ADCCON3 = ((ADCCON3 & 0x3F) | ((uint8_t)(res) << 6));
}

void hal_adc_set_data_just ( hal_adc_data_just_t just )

Function to set the ADC data output justification. This function sets the ADC output to be left or right justified.

Parameters:

just	The resolution of the ADC

Definition at line 74 of file hal_adc.c.

{ // Update "rljust" bit
  ADCCON3 = ((ADCCON3 & 0xDF) | (((uint8_t)(just) << 5) & ~0xDF));
}

void hal_adc_start ( void )

Function to start the ADC conversion. This function starts the conversion.

< The value of bit 7

Definition at line 80 of file hal_adc.c.

{
  uint8_t cnt = ADC_STARTUP_CNT;             // Get the counter value
  ADCCON1 = ADCCON1 | BIT_7;                 // Set "pwrup" bit

  while(cnt--){}                         // Wait for busy bit to stabilize
}

uint8_t hal_adc_read_LSB ( void )

Function that returns the LSB of the data from the ADC. This function returns the LSB of the current data stored in the ADC.

Returns:: LSB of data from the ADC

Definition at line 89 of file hal_adc.c.

{
  return ADCDATL;                            // Return value stored in ADCDATL
}

uint8_t hal_adc_read_MSB ( void )

Function that returns the MSB of the data from the ADC. This function returns the MSB of the current data stored in the ADC.

Returns:: MSB of data from the ADC

Definition at line 94 of file hal_adc.c.

{
  return ADCDATH;                            // Return value stored in ADCDATH
}

_Bool hal_adc_busy ( void )

Function that returns the status of the ADC. This function returns true if the ADC is busy.

Returns:: ADC busy bit

Return values:

FALSE	no conversion in progress
TRUE	conversion in progress

< The value of bit 6

Definition at line 99 of file hal_adc.c.

{
  return ((ADCCON1 & BIT_6));            // Return status of "busy" bit
}

hal_adc_overflow_t hal_adc_get_overflow_status ( void )

Function that returns the flow status of the ADC. Use this function to check for overflow and/or underflow.

Returns:: Overflow status

< The value of bit 3

< The value of bit 4

Definition at line 104 of file hal_adc.c.

{
  return (hal_adc_overflow_t)((ADCCON3 & (BIT_3 | BIT_4)) >> 3);
}

Analog to Digital Converter (hal_adc) [nRF24LE1 HAL]

Defines

Enumerations

SETUP FUNCTIONS

OPERATION FUNCTIONS

STATUS FUNCTIONS

Define Documentation

Enumeration Type Documentation

Function Documentation

Analog to Digital Converter (hal_adc)
[nRF24LE1 HAL]