ADC

概述

模数转换器（analog-to-digital converter，通常称为ADC）是一种模拟与数字转换器，支持12路外部模拟输入和若干内部模拟信号选择。 ADC支持以下四种模式：单次单通道转换、连续单通道转换、单次多通道转换和连续多通道转换模式。 转换结果为12/14/16bits左对齐模式。ADC拥有深度为32的FIFO，支持多种中断和DMA操作。 ADC除了用于普通模拟信号测量外，还可以用于测量供电电压， 此外ADC还可以通过测量内/外部二极管电压用于温度检测。

注解

adc更多资料请参考 BL602参考手册 。

应用实例

ADC实例： customer_app/peripheral/demo_adc 。

API参考

Header File

  • components/platform/hosal/include/hosal_adc.h

Functions

int hosal_adc_init(hosal_adc_dev_t *adc)

Initialises an ADC interface, Prepares an ADC hardware interface for sampling.

Return
  • 0 on success
  • EIO if an error occurred with any step
Parameters
  • adc: the interface which should be initialised

int hosal_adc_add_channel(hosal_adc_dev_t *adc, uint32_t channel)

Add a channel to an ADC interface.

Return
  • 0 on success
  • EIO if an error occurred with any step
Parameters
  • adc: the interface which should be sampled
  • channel: adc channel

int hosal_adc_remove_channel(hosal_adc_dev_t *adc, uint32_t channel)

Remove a channel to an ADC interface.

Return
  • 0 on success
  • EIO if an error occurred with any step
Parameters
  • adc: the interface which should be sampled
  • channel: adc channel

hosal_adc_dev_t *hosal_adc_device_get(void)

Takes adc device handle from an ADC interface.

Return
  • other get adc device success
  • NULL if an error occurred with any step

int hosal_adc_value_get(hosal_adc_dev_t *adc, uint32_t channel, uint32_t timeout)

Takes a single sample from an ADC interface.

Return
  • other get adc data success
  • -1 if an error occurred with any step
Parameters
  • adc: the interface which should be sampled
  • channel: adc channel
  • timeout: ms timeout

int hosal_adc_tsen_value_get(hosal_adc_dev_t *adc)

Takes a tsen sample from an ADC interface.

Return
  • other get adc data success
  • -1 if an error occurred with any step
Parameters
  • adc: the interface which should be sampled

int hosal_adc_sample_cb_reg(hosal_adc_dev_t *adc, hosal_adc_cb_t cb)

ADC sampling cb register.

Return
  • 0 on success
  • EIO if an error occurred with any step
Parameters
  • adc: the ADC interface
  • cb: Non-zero pointer is the sample callback handler NULL pointer for send unregister operation adc in cb must be the same pointer with adc pointer passed to hosal_adc_sample_cb_reg driver must notify upper layer by calling cb if ADC data is ready in HW or memory(DMA)

int hosal_adc_start(hosal_adc_dev_t *adc, void *data, uint32_t size)

ADC sampling start.

Return
  • 0 on success
  • EIO if an error occurred with any step
Parameters
  • adc: the ADC interface
  • data: adc data buffer
  • size: data buffer size aligned with resolution (until the next power of two)

int hosal_adc_stop(hosal_adc_dev_t *adc)

ADC sampling stop.

Return
  • 0 on success
  • EIO if an error occurred with any step
Parameters
  • adc: the ADC interface

int hosal_adc_finalize(hosal_adc_dev_t *adc)

De-initialises an ADC interface, Turns off an ADC hardware interface.

Return
  • 0 on success
  • EIO if an error occurred with any step
Parameters
  • adc: the interface which should be de-initialised

Structures

struct hosal_adc_data_t

ADC data type.

Public Members

uint32_t size

sampled data size

void *data

sampled data, aligned with resolution (until the next power of two)

struct hosal_adc_config_t

Define ADC config args.

Public Members

uint32_t sampling_freq

sampling frequency in Hz

uint32_t pin

adc pin

hosal_adc_sample_mode_t mode

adc sampling mode

uint8_t sample_resolution

adc sampling resolution

struct hosal_adc_dev_t

Define ADC dev hosal handle.

Public Members

uint8_t port

adc port

hosal_adc_config_t config

adc config

hosal_dma_chan_t dma_chan

adc dma channel

hosal_adc_irq_t cb

adc callback

void *p_arg

p_arg data

void *priv

priv data

Macros

HOSAL_WAIT_FOREVER

Define the wait forever timeout macro.

Type Definitions

typedef enum __ADC_INT_EVENTS__ hosal_adc_event_t

ADC interrupt events.

typedef void (*hosal_adc_irq_t)(void *parg)

ADC interrupt function.

Parameters
  • parg: Set the custom parameters specified

typedef void (*hosal_adc_cb_t)(hosal_adc_event_t event, void *data, uint32_t size)

ADC interrupt callback.

Parameters
  • parg: Set the custom parameters specified when the callback function is set

Enumerations

enum __ADC_INT_EVENTS__

ADC interrupt events.

Values:

HOSAL_ADC_INT_OV

Overrun error.

HOSAL_ADC_INT_EOS

End of sample.

HOSAL_ADC_INT_DMA_TRH

DMA transceive half.

HOSAL_ADC_INT_DMA_TRC

DMA transceive complete.

HOSAL_ADC_INT_DMA_TRE

@briefDMA transceive error

enum hosal_adc_sample_mode_t

ADC MODE type.

Values:

HOSAL_ADC_ONE_SHOT

Single time sampling.

HOSAL_ADC_CONTINUE

Continuous sampling.