dac.c

philips arm7 lpc2103的常用功能的库函数第二部分

/***********************************************Copyright (c)*********************************************
**                                Guangzou ZLG-MCU Development Co.,LTD.
**                                     
**                                       http://www.zlgmcu.com
**
**--------------File Info---------------------------------------------------------------------------------
** File name:			    DAC.c
** Last modified Date:      2007-12-01
** Last Version:		    1.0
** Descriptions:		    I2C函数实现，采用设备描述符来操作
**
**--------------------------------------------------------------------------------------------------------
** Created by:			    lixiaocheng
** Created date:		    2007-12-01
** Version:				    1.0
** Descriptions:		    无
**
*********************************************************************************************************/
#include "Config.h"
#include "DacPrivate.h"
#include "Dac.h"                                                        
                                                        
/*********************************************************************************************************
   定义操作I2C器件的结构体，有多个器件就需要声明多个结构体
*********************************************************************************************************/
static __DAC_INFO   __Dac0Data;

/*********************************************************************************************************
   下面使用指针数组来保存结构体指针,方便对该驱动的扩展
*********************************************************************************************************/
const __PDAC_INFO   __GpdacDateTab[__DAC_MAX_NUM] = {&__Dac0Data};

/*********************************************************************************************************
   下面定义了I2C0基地址值，如果有多个I2C器件可以在该位置添加相应的基地址即可
*********************************************************************************************************/
const uint32        __GuiDacBaseAddrTab[__DAC_MAX_NUM] = {DAC_BASE_ADDR};

/*********************************************************************************************************
** Function name:           dacInit()
** Descriptions:            DAC初始化函数，返回错误表示ID错误
** Input parameters:        uiArgID DAC的ID
** Output parameters:       NONE
** Returned value:          OPERATE_FAIL    操作失败
**                          OPERATE_SUCCESS 操作成功
*********************************************************************************************************/
int32 dacInit (uint32 uiArgID)
{
    if (uiArgID >= __DAC_MAX_NUM) {
        return OPERATE_FAIL;
    }

    __GpdacDateTab[uiArgID]->puiAddrBase = (uint32 *)__GuiDacBaseAddrTab[uiArgID];
    __GpdacDateTab[uiArgID]->uiOffBase   = 0;
    
    return OPERATE_SUCCESS;
}

/*********************************************************************************************************
** Function name:           dacWrite()
** Descriptions:            DAC转换电压输出函数，注意写完值要等待3us时间，才能使转换结束，返回错误表示ID错误
** Input parameters:        uiArgID         DAC的设备号
**                          uiArgValue      要输出的电压值单位mv
** Output parameters:       NONE
** Returned value:          OPERATE_FAIL    操作失败
**                          OPERATE_SUCCESS 操作成功
*********************************************************************************************************/
int32 dacWrite (uint32 uiArgID, uint32 uiArgValue)
{
    volatile    uint32     *puiAddrBase;
                uint32      uiOffBase;
                uint32      uiValue = 0;
    
    if (uiArgID >= __DAC_MAX_NUM) {
        return OPERATE_FAIL;
    }
    
    puiAddrBase = __GpdacDateTab[uiArgID]->puiAddrBase;
    uiOffBase   = __GpdacDateTab[uiArgID]->uiOffBase;
    
    
    if (uiArgValue > __DAC_REF ) {
        uiArgValue = __DAC_REF;
    }
    
    uiArgValue = (uiArgValue * 1024) / __DAC_REF;
    
    uiValue = (__DAC_MAX_OUT_CURRENT << 16) |
              (uiArgValue << 6);
              
    puiAddrBase[__B_DAC_CR << uiOffBase] = uiValue;
    
    return OPERATE_SUCCESS;
} 
/*********************************************************************************************************
   END FILE
*********************************************************************************************************/