int SendCMD(char *devName, char addr, uint16_t command)
{
int fd = -1;
uint8_t cmdBuf[2L] = {0};
struct i2c_rdwr_ioctl_data i2c_data;
fd = open(devName, O_RDWR); //獲取I2C設(shè)備句柄
i2c_data.nmsgs = 1;
i2c_data.msgs = (struct i2c_msg *)malloc(i2c_data.nmsgs * sizeof(struct 
i2c_msg));
ioctl(fd, I2C_TIMEOUT, 1);
ioctl(fd, I2C_RETRIES, 2L);
cmdBuf[0] = command >> 8L; //對(duì)指令數(shù)據(jù)進(jìn)行處理 高八位和低八位
cmdBuf[1] = command & 0xFF;
i2c_data.msgs[0].len = 2L;
i2c_data.msgs[0].addr = addr;
i2c_data.msgs[0].flags = 0;
i2c_data.msgs[0].buf = cmdBuf;
ioctl(fd, I2C_RDWR, (unsigned long)&i2c_data); //將數(shù)據(jù)寫(xiě)入進(jìn)行傳輸
free(i2c_data.msgs);
close(fd);
return 0;
}
// 再定義一些數(shù)據(jù)轉(zhuǎn)換函數(shù)和校驗(yàn)函數(shù) 簡(jiǎn)單的數(shù)據(jù)轉(zhuǎn)換 忽略
int ConvertTH(uint8_t tempRH, float *rawTemp, float *rawHum);
...

int main(int argc, char *argv[])
{
char *dev_name = "/dev/i2c-5";
SendCMD(dev_name,ADDR,0x3093) //重啟
usleep(50L * 1000L);
SendCMD(dev_name,ADDR,0x202F) //開(kāi)始測(cè)量
usleep(50L * 1000L);
int fd = -1;
struct i2c_rdwr_ioctl_data i2c_data;
uint8_t rawData[6L] = {0};
float rawTemp = 0, rawHum = 0;
fd = open(devName, O_RDWR);
i2c_data.nmsgs = 1;
i2c_data.msgs = (struct i2c_msg *)malloc(i2c_data.nmsgs * sizeof(struct 
i2c_msg));
i2c_data.msgs[0].len = 6L;
i2c_data.msgs[0].addr = addr;
i2c_data.msgs[0].flags = 1;
i2c_data.msgs[0].buf = rawData;
ioctl(fd, I2C_RDWR, (unsigned long)&i2c_data);
free(i2c_data.msgs);
close(fd);
ConvertTH(rawData, &rawTemp, &rawHum);
printf("Temp: %.2f°C\nHum: %.2f°F",rawTemp,rawHum);
return 0;
}

//device_info.hcs 配置參考
root {
device_info {
match_attr = "hdf_manager";
device_i2c :: device {
device0 :: deviceNode {
policy = 2;
priority = 50;
permission = 0644;
moduleName = "HDF_PLATFORM_I2C_MANAGER";
serviceName = "HDF_PLATFORM_I2C_MANAGER";
deviceMatchAttr = "hdf_platform_i2c_manager";
}
device1 :: deviceNode {
policy = 0; // 等于0，不需要發(fā)布服務(wù)
priority = 55; // 驅(qū)動(dòng)啟動(dòng)優(yōu)先級(jí)
permission = 0644; // 驅(qū)動(dòng)創(chuàng)建設(shè)備節(jié)點(diǎn)權(quán)限
moduleName = "hi35xx_i2c_driver"; 
//【必要】用于指定驅(qū)動(dòng)名稱(chēng)，需要與期望的驅(qū)動(dòng)Entry中的moduleName一致;
serviceName = "HI35XX_I2C_DRIVER"; //【必要】驅(qū)動(dòng)對(duì)外發(fā)布服務(wù)的名稱(chēng)，必須唯一
deviceMatchAttr = 
"hisilicon_hi35xx_i2c";//【必要】用于配置控制器私有數(shù)據(jù)，要與i2c_config.hcs中對(duì)應(yīng)控制器保持一致
// 具體的控制器信息在 i2c_config.hcs 中
}
}
}
}

// i2c_config.hcs 配置參考 (需要根據(jù)使用的開(kāi)發(fā)板配置)
root {
platform {
i2c_config {
match_attr = 
"hisilicon_hi35xx_i2c";//【必要】需要和device_info.hcs中的deviceMatchAttr值一致
template i2c_controller { //模板公共參數(shù)，繼承該模板的節(jié)點(diǎn)如果使用模板中的默認(rèn)值，則節(jié)點(diǎn)字段可以缺省
bus = 0; //【必要】i2c 識(shí)別號(hào)
reg_pbase = 0x120b0000; //【必要】物理基地址
reg_size = 0xd1; //【必要】寄存器位寬
irq = 0; //【可選】根據(jù)廠商需要來(lái)使用
freq = 400000; //【可選】根據(jù)廠商需要來(lái)使用
clk = 50000000; //【可選】根據(jù)廠商需要來(lái)使用
}
controller_0x120b0000 :: i2c_controller {
bus = 0;
}
controller_0x120b1000 :: i2c_controller {
bus = 1;
reg_pbase = 0x120b1000;
}
...
}
}
}

struct I2cMsg {
/** Address of the I2C device */
uint16_t addr;
/** Address of the buffer for storing transferred data */
uint8_t *buf;
/** Length of the transferred data */
uint16_t len;
/**
* Transfer Mode Flag | Description
* ------------| -----------------------
* I2C_FLAG_READ | Read flag
* I2C_FLAG_ADDR_10BIT | 10-bit addressing flag
* I2C_FLAG_READ_NO_ACK | No-ACK read flag
* I2C_FLAG_IGNORE_NO_ACK | Ignoring no-ACK flag
* I2C_FLAG_NO_START | No START condition flag
* I2C_FLAG_STOP | STOP condition flag
*/
uint16_t flags;
};

//number指I2C所掛載的總線號(hào)
DevHandle I2cOpen(int16_t number);
//handle是I2cOpen()返回的設(shè)備句柄
void I2cClose(DevHandle handle);
//msgs所要傳輸?shù)臄?shù)據(jù)結(jié)構(gòu)體，count是傳輸結(jié)構(gòu)體的大小
int32_t I2cTransfer(DevHandle handle, struct I2cMsg *msgs, int16_t 
count);

#include //標(biāo)準(zhǔn)輸入輸出
#include //使用到usleep()進(jìn)程掛起函數(shù)
#include "i2c_if.h" //HDF i2c 接口
#include "hdf_log.h" //日志打印頭文件

// 重新定義結(jié)構(gòu)體方便使用
typedef struct
{
struct I2cMsg * i2cMsg;
uint8_t msgLen; //i2cMsg的長(zhǎng)度
} I2cMessage;
//定義命令發(fā)送函數(shù)
int32_t SendCMD(DevHandle handle,uint16_t command)
{
int32_t ret;
I2cMessage i2cMessage;
i2cMessage.msgLen = 1;
i2cMessage.i2cMsg = new I2cMsg[1]; //申請(qǐng)內(nèi)存
uint8_t cmdBuf[2L] = {0};
cmdBuf[0] = command >> 8L; //將命令拆分成高低位分別保存
cmdBuf[1] = command & 0xFF;
i2cMessage.i2cMsg[0].len = 2L;
i2cMessage.i2cMsg[0].addr = ADDR;
i2cMessage.i2cMsg[0].flags = WRITE_FLAGS;
i2cMessage.i2cMsg[0].buf = cmdBuf;
ret = I2cTransfer(handle,i2cMessage.i2cMsg,i2cMessage.msgLen);
if(ret < 0){
LOGE("%s: SendCommend faided",__func__);
delete i2cMessage.i2cMsg;
return -1;
}
delete i2cMessage.i2cMsg; //釋放內(nèi)存
usleep(50L * 1000L); //等待發(fā)送完成
return 1;
}

int main(int argc, char** argv)
{
/**
* 數(shù)據(jù)初始化
*/
DevHandle i2cHandle;
/**
* 獲取句柄
*/
i2cHandle = I2cOpen(BUSID);
if(i2cHandle == NULL){
LOGE("%s:get handle failed",__func__);
I2cClose(i2cHandle);
return 0;
}
/**
* 發(fā)送命令
*/
SendCMD(i2cHandle,0x3093); //關(guān)閉reset命令
SendCMD(i2cHandle,0x202F); //發(fā)送命令 repeatability=Low mps=0.5
/**
* 接收數(shù)據(jù)
*/
I2cMessage i2cMessage;
i2cMessage.msgLen = 1;
i2cMessage.i2cMsg = new I2cMsg[1];
uint8_t regData[6L] = {0};
i2cMessage.i2cMsg[0].len = 6L;
i2cMessage.i2cMsg[0].addr = ADDR;
i2cMessage.i2cMsg[0].flags = READ_FLAGS;
i2cMessage.i2cMsg[0].buf = regData;
I2cTransfer(i2cHandle,i2cMessage.i2cMsg,i2cMessage.msgLen);
delete i2cMessage.i2cMsg;
/**
* 數(shù)據(jù)處理
*/
uint16_t value = 0;
value = regData[0] << 8;
value = value | regData[1];
printf("Temperature: %.2f C\n",175.0f * (float)value / 65535.0f - 45.0f);
value = 0;
value = regData[3] << 8;
value = value | regData[4];
printf("Humidity: %.2f H\n",100.0f * (float)value / 65535.0f);
/**
* 關(guān)閉設(shè)備
*/
I2cClose(i2cHandle);
return 0;
}

/**
* 模塊定義
*/
static napi_module i2cHDF_demoModule = {
.nm_version = 1,
.nm_flags = 0,
.nm_filename = nullptr,
.nm_register_func = registerI2cHDF_DemoApis,
.nm_modname = "i2chdf_demo",
.nm_priv = ((void *)0),
.reserved = {0},
};
/**
* 模塊注冊(cè)
*/
extern "C" __attribute__((constructor)) void RegisterI2cHDFoModule(void)
{
napi_module_register(&i2cHDF_demoModule);
}

int32_t SendCMD(DevHandle handle,uint16_t command)
{
int32_t ret;
struct I2cMsg * i2cMsg;
int msgLen = 1;
i2cMsg = new I2cMsg[msgLen];
uint8_t cmdBuf[2L] = {0};
cmdBuf[0] = command >> 8L;
cmdBuf[1] = command & 0xFF;
i2cMsg[0].len = 2L;
i2cMsg[0].addr = ADDR;
i2cMsg[0].flags = WRITE_FLAGS;
i2cMsg[0].buf = cmdBuf;
ret = I2cTransfer(handle,i2cMsg,msgLen);
delete i2cMsg;
usleep(50L * 1000L);
return 1;
}
/**
* 接口定義
*/
static napi_value readI2cBuf(napi_env env,napi_callback_info info)
{
napi_value ret;
DevHandle i2cHandle;
i2cHandle = I2cOpen(BUSID);
SendCMD(i2cHandle,0x3093);
SendCMD(i2cHandle,0x202F);
struct I2cMsg * i2cMsg;
int msgLen = 1;
i2cMsg = new I2cMsg[msgLen];
uint8_t regData[6L] = {0};
i2cMsg[0].len = 6L;
i2cMsg[0].addr = ADDR;
i2cMsg[0].flags = READ_FLAGS;
i2cMsg[0].buf = regData;
I2cTransfer(i2cHandle,i2cMsg,msgLen);
delete i2cMsg;
uint16_t value = 0;
double sHTTemp = 0;
value = regData[0] << 8;
value = value | regData[1];
sHTTemp = 175.0f * (double)value / 65535.0f - 45.0f;
//設(shè)計(jì)思路與上HDF大同小異，只不過(guò)將最后獲取的值通過(guò)轉(zhuǎn)換再返回
//此處只處理返回溫度的值，方便演示
NAPI_CALL(env, napi_create_double(env, sHTTemp, &ret));
return ret;
}
/**
* 接口注冊(cè)
*/
static napi_value registerI2cHDF_DemoApis(napi_env env, napi_value 
exports)
{
napi_property_descriptor desc[] = {
DECLARE_NAPI_FUNCTION("readI2cBuf",readI2cBuf), //NAPI名字，上面的函數(shù)
};
NAPI_CALL(env,napi_define_properties(env,exports,sizeof(desc)/sizeof(desc[0]),desc));
return exports;
}

function readI2cBuf(): number;

import i2chdf from '@ohos.i2chdf'
@Entry
@Component
struct Index {
@State message: string = 'Temperature： '+ i2chdf.readI2cBuf().toFixed(2) + 
'°C';
aboutToAppear(): void{
var Id = setInterval(() =>{
this.message = 'Temperature： '+ i2chdf.readI2cBuf().toFixed(2) + '°C';
},1000)
}
build() {
Row() {
Column() {
Text(this.message)
.fontSize(50)
.fontWeight(FontWeight.Bold)
}
.width('100%')
}
.height('100%')
}
}