DAC

DAC 的协作图:

结构体
struct	rt_dac_ops
struct	rt_dac_device

类型定义
typedef struct rt_dac_device *	rt_dac_device_t

枚举
enum	rt_dac_cmd_t { RT_DAC_CMD_ENABLE = RT_DEVICE_CTRL_BASE(DAC) + 0 , RT_DAC_CMD_DISABLE = RT_DEVICE_CTRL_BASE(DAC) + 1 , RT_DAC_CMD_GET_RESOLUTION = RT_DEVICE_CTRL_BASE(DAC) + 2 }

函数
rt_err_t	rt_hw_dac_register (rt_dac_device_t dac, const char *name, const struct rt_dac_ops *ops, const void *user_data)
rt_err_t	rt_dac_write (rt_dac_device_t dev, rt_uint32_t channel, rt_uint32_t value)
rt_err_t	rt_dac_enable (rt_dac_device_t dev, rt_uint32_t channel)
rt_err_t	rt_dac_disable (rt_dac_device_t dev, rt_uint32_t channel)

详细描述

DAC driver api

Example

#include <rtthread.h>
#include <rtdevice.h>
#include <stdlib.h>
#define DAC_DEV_NAME        "dac1"
#define DAC_DEV_CHANNEL     1
#define REFER_VOLTAGE       330
#define CONVERT_BITS        (1 << 12)
 
static int dac_vol_sample(int argc, char *argv[])
{
    rt_dac_device_t dac_dev;
    rt_uint32_t value, vol;
    rt_err_t ret = RT_EOK;
 
    dac_dev = (rt_dac_device_t)rt_device_find(DAC_DEV_NAME);
    if (dac_dev == RT_NULL)
    {
        rt_kprintf("dac sample run failed! can't find %s device!\n", DAC_DEV_NAME);
        return -RT_ERROR;
    }
 
    ret = rt_dac_enable(dac_dev, DAC_DEV_CHANNEL);
 
    value = atoi(argv[1]);
    rt_dac_write(dac_dev, DAC_DEV_NAME, DAC_DEV_CHANNEL, value);
    rt_kprintf("the value is :%d \n", value);
 
    vol = value * REFER_VOLTAGE / CONVERT_BITS;
    rt_kprintf("the voltage is :%d.%02d \n", vol / 100, vol % 100);
 
    rt_thread_mdelay(500);
 
    ret = rt_dac_disable(dac_dev, DAC_DEV_CHANNEL);
 
    return ret;
}
MSH_CMD_EXPORT(dac_vol_sample, dac voltage convert sample);

类型定义说明

rt_dac_device_t

typedef struct rt_dac_device* rt_dac_device_t

在文件 dac.h 第 90 行定义.

枚举类型说明

rt_dac_cmd_t

enum rt_dac_cmd_t

枚举值
RT_DAC_CMD_ENABLE	RT_DEVICE_CTRL_BASE(DAC) + 0
RT_DAC_CMD_DISABLE	RT_DEVICE_CTRL_BASE(DAC) + 1
RT_DAC_CMD_GET_RESOLUTION	RT_DEVICE_CTRL_BASE(DAC) + 2

在文件 dac.h 第 92 行定义.

{
    RT_DAC_CMD_ENABLE = RT_DEVICE_CTRL_BASE(DAC) + 0,
    RT_DAC_CMD_DISABLE = RT_DEVICE_CTRL_BASE(DAC) + 1,
    RT_DAC_CMD_GET_RESOLUTION = RT_DEVICE_CTRL_BASE(DAC) + 2,
} rt_dac_cmd_t;

函数说明

rt_hw_dac_register()

rt_err_t rt_hw_dac_register	(	rt_dac_device_t	dac,
		const char *	name,
		const struct rt_dac_ops *	ops,
		const void *	user_data )

Register a DAC device

参数

dac	DAC device
name	DAC name
ops	the operations of DAC device
user_data	device private data

返回

rt_err_t error code

rt_dac_write()

rt_err_t rt_dac_write	(	rt_dac_device_t	dev,
		rt_uint32_t	channel,
		rt_uint32_t	value )

set the value of DAC

参数

dev	DAC device
channel	DAC channel
value	the value of DAC

返回

rt_err_t error code

rt_dac_enable()

rt_err_t rt_dac_enable	(	rt_dac_device_t	dev,
		rt_uint32_t	channel )

enable the DAC channel

参数

dev	DAC device
channel	DAC channel

返回

rt_err_t error code

rt_dac_disable()

rt_err_t rt_dac_disable	(	rt_dac_device_t	dev,
		rt_uint32_t	channel )

disable the DAC channel

参数

dev	DAC device
channel	DAC channel

返回

rt_err_t error code