nrf52832 IIC读取sht30温湿度传感器
1、平台的条件
1.1 软件平台：sdk14.2
1.2 硬件平台: nrf52832
2 说明：
只是介绍代码怎么使用，直接点
QQ: 1297311998 ,如果有什么问题，请高手不吝赐教
2、nrf模拟 iic 驱动
以下是模拟iic驱动代码，基于nrf，可以直接用
2.1 添加.h文件
#ifndef IIC_H
#define IIC_H
#include 2.2 添加 iic .c文件
/* Copyright (c) 2009 Nordic Semiconductor. All Rights Reserved.
*
* The information contained herein is property of Nordic Semiconductor ASA.
* Terms and conditions of usage are described in detail in NORDIC
* SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
*
* Licensees are granted free, non-transferable use of the information. NO
* WARRANTY of ANY KIND is provided. This heading must NOT be removed from
* the file.
*
*/
#include "iic_io.h"
#include "utility.h"
#define TWI_DELAY_HRS() delay_us(1)
#define IIC_DELAY(A) delay_us((A)*100)
uint8_t sda_hrs,scl_hrs;
static bool twi_master_clear_bus(void);
static bool twi_master_issue_startcondition(void);
static bool twi_master_issue_stopcondition(void);
static bool twi_master_clock_byte(uint_fast8_t databyte);
static bool twi_master_clock_byte_in(uint8_t * databyte, bool ack);
static bool twi_master_wait_while_scl_low(void);
bool hrs_iic_init(uint8_t sda_pin,uint8_t scl_pin)
{
// Configure both pins to output Standard 0, No-drive (open-drain) 1
sda_hrs =sda_pin;
scl_hrs=scl_pin;
TWI_SDA_STANDARD0_NODRIVE1_HRS();
TWI_SCL_STANDARD0_NODRIVE1_HRS(); /*lint !e416 "Creation of out of bounds pointer" */
// Configure SCL as output
TWI_SCL_HIGH_HRS();
TWI_SCL_OUTPUT_HRS();
// Configure SDA as output
TWI_SDA_HIGH_HRS();
TWI_SDA_OUTPUT_HRS();
return twi_master_clear_bus();
}
bool hrs_iic_transfer(uint8_t address, uint8_t * data, uint16_t data_length, bool issue_stop_condition)
{
bool transfer_succeeded = true;
transfer_succeeded &= twi_master_issue_startcondition();
transfer_succeeded &= twi_master_clock_byte(address);
if (address & TWI_READ_BIT_HRS)
{
/* Transfer direction is from Slave to Master */
while (data_length-- && transfer_succeeded)
{
// To indicate to slave that we've finished transferring last data byte
// we need to NACK the last transfer.
if (data_length == 0)
{
transfer_succeeded &= twi_master_clock_byte_in(data, (bool)false);
}
else
{
transfer_succeeded &= twi_master_clock_byte_in(data, (bool)true);
}
data++;
}
}
else
{
/* Transfer direction is from Master to Slave */
while (data_length-- && transfer_succeeded)
{
transfer_succeeded &= twi_master_clock_byte(*data);
data++;
}
}
if (issue_stop_condition || !transfer_succeeded)
{
transfer_succeeded &= twi_master_issue_stopcondition();
}
return transfer_succeeded;
}
/**
* @brief Function for detecting stuck slaves and tries to clear the bus.
*
* @return
* @retval false Bus is stuck.
* @retval true Bus is clear.
*/
static bool twi_master_clear_bus(void)
{
bool bus_clear;
uint_fast8_t i;
TWI_SDA_HIGH_HRS();
TWI_SCL_HIGH_HRS();
TWI_DELAY_HRS();
if (TWI_SDA_READ_HRS() == 1 && TWI_SCL_READ_HRS() == 1)
{
bus_clear = true;
}
else if (TWI_SCL_READ_HRS() == 1)
{
bus_clear = false;
// Clock max 18 pulses worst case scenario(9 for master to send the rest of command and 9 for slave to respond) to SCL line and wait for SDA come high
for ( i = 18; i--;)
{
TWI_SCL_LOW_HRS();
TWI_DELAY_HRS();
TWI_SCL_HIGH_HRS();
TWI_DELAY_HRS();
if (TWI_SDA_READ_HRS() == 1)
{
bus_clear = true;
break;
}
}
}
else
{
bus_clear = false;
}
return bus_clear;
}
/**
* @brief Function for issuing TWI START condition to the bus.
*
* START condition is signaled by pulling SDA low while SCL is high. After this function SCL and SDA will be low.
*
* @return
* @retval false Timeout detected
* @retval true Clocking succeeded
*/
static bool twi_master_issue_startcondition(void)
{
// Make sure both SDA and SCL are high before pulling SDA low.
TWI_SDA_HIGH_HRS();
TWI_DELAY_HRS();
if (!twi_master_wait_while_scl_low())
{
return false;
}
TWI_SDA_LOW_HRS();
TWI_DELAY_HRS();
// Other module function expect SCL to be low
TWI_SCL_LOW_HRS();
TWI_DELAY_HRS();
return true;
}
/**
* @brief Function for issuing TWI STOP condition to the bus.
*
* STOP condition is signaled by pulling SDA high while SCL is high. After this function SDA and SCL will be high.
*
* @return
* @retval false Timeout detected
* @retval true Clocking succeeded
*/
static bool twi_master_issue_stopcondition(void)
{
TWI_SDA_LOW_HRS();
TWI_DELAY_HRS();
if (!twi_master_wait_while_scl_low())
{
return false;
}
TWI_SDA_HIGH_HRS();
TWI_DELAY_HRS();
return true;
}
/**
* @brief Function for clocking one data byte out and reads slave acknowledgment.
*
* Can handle clock stretching.
* After calling this function SCL is low and SDA low/high depending on the
* value of LSB of the data byte.
* SCL is expected to be output and low when entering this function.
*
* @param databyte Data byte to clock out.
* @return
* @retval true Slave acknowledged byte.
* @retval false Timeout or slave didn't acknowledge byte.
*/
static bool twi_master_clock_byte(uint_fast8_t databyte)
{
uint_fast8_t i;
bool transfer_succeeded = true;
/** @snippet [TWI SW master write] */
// Make sure SDA is an output
TWI_SDA_OUTPUT_HRS();
// MSB first
for ( i = 0x80; i != 0; i >>= 1)
{
TWI_SCL_LOW_HRS();
TWI_DELAY_HRS();
if (databyte & i)
{
TWI_SDA_HIGH_HRS();
}
else
{
TWI_SDA_LOW_HRS();
}
if (!twi_master_wait_while_scl_low())
{
transfer_succeeded = false; // Timeout
break;
}
}
// Finish last data bit by pulling SCL low
TWI_SCL_LOW_HRS();
TWI_DELAY_HRS();
/** @snippet [TWI SW master write] */
// Configure TWI_SDA pin as input for receiving the ACK bit
TWI_SDA_INPUT_HRS();
// Give some time for the slave to load the ACK bit on the line
TWI_DELAY_HRS();
// Pull SCL high and wait a moment for SDA line to settle
// Make sure slave is not stretching the clock
transfer_succeeded &= twi_master_wait_while_scl_low();
// Read ACK/NACK. NACK == 1, ACK == 0
transfer_succeeded &= !(TWI_SDA_READ_HRS());
// Finish ACK/NACK bit clock cycle and give slave a moment to release control
// of the SDA line
TWI_SCL_LOW_HRS();
TWI_DELAY_HRS();
// Configure TWI_SDA pin as output as other module functions expect that
TWI_SDA_OUTPUT_HRS();
return transfer_succeeded;
}
/**
* @brief Function for clocking one data byte in and sends ACK/NACK bit.
*
* Can handle clock stretching.
* SCL is expected to be output and low when entering this function.
* After calling this function, SCL is high and SDA low/high depending if ACK/NACK was sent.
*
* @param databyte Data byte to clock out.
* @param ack If true, send ACK. Otherwise send NACK.
* @return
* @retval true Byte read succesfully
* @retval false Timeout detected
*/
static bool twi_master_clock_byte_in(uint8_t *databyte, bool ack)
{
uint_fast8_t i;
uint_fast8_t byte_read = 0;
bool transfer_succeeded = true;
/** @snippet [TWI SW master read] */
// Make sure SDA is an input
TWI_SDA_INPUT_HRS();
// SCL state is guaranteed to be high here
// MSB first
for ( i = 0x80; i != 0; i >>= 1)
{
if (!twi_master_wait_while_scl_low())
{
transfer_succeeded = false;
break;
}
if (TWI_SDA_READ_HRS())
{
byte_read |= i;
}
else
{
// No need to do anything
}
TWI_SCL_LOW_HRS();
TWI_DELAY_HRS();
}
// Make sure SDA is an output before we exit the function
TWI_SDA_OUTPUT_HRS();
/** @snippet [TWI SW master read] */
*databyte = (uint8_t)byte_read;
// Send ACK bit
// SDA high == NACK, SDA low == ACK
if (ack)
{
TWI_SDA_LOW_HRS();
}
else
{
TWI_SDA_HIGH_HRS();
}
// Let SDA line settle for a moment
TWI_DELAY_HRS();
// Drive SCL high to start ACK/NACK bit transfer
// Wait until SCL is high, or timeout occurs
if (!twi_master_wait_while_scl_low())
{
transfer_succeeded = false; // Timeout
}
// Finish ACK/NACK bit clock cycle and give slave a moment to react
TWI_SCL_LOW_HRS();
TWI_DELAY_HRS();
return transfer_succeeded;
}
#include "nrf_delay.h"
/**
* @brief Function for pulling SCL high and waits until it is high or timeout occurs.
*
* SCL is expected to be output before entering this function.
* @note If TWI_MASTER_TIMEOUT_COUNTER_LOAD_VALUE is set to zero, timeout functionality is not compiled in.
* @return
* @retval true SCL is now high.
* @retval false Timeout occurred and SCL is still low.
*/
static bool twi_master_wait_while_scl_low(void)
{
#if TWI_MASTER_TIMEOUT_COUNTER_LOAD_VALUE_HRS != 0
uint32_t volatile timeout_counter = TWI_MASTER_TIMEOUT_COUNTER_LOAD_VALUE_HRS;
#endif
// Pull SCL high just in case if something left it low
TWI_SCL_HIGH_HRS();
TWI_DELAY_HRS();
while (TWI_SCL_READ_HRS() == 0)
{
// If SCL is low, one of the slaves is busy and we must wait
#if TWI_MASTER_TIMEOUT_COUNTER_LOAD_VALUE_HRS != 0
IIC_DELAY(20);
// TWI_DELAY_HRS();
if (timeout_counter-- == 0)
{
// If timeout_detected, return false
return false;
}
#endif
}
return true;
}
/*lint --flb "Leave library region" */
3 sht30 应用读取函数
3.1 添加.h文件
#ifndef shtsensor_iicApi_h_
#define shtsensor_iicApi_h_
#include 3.2 添加.c文件
sht30 初始化
uint8_t TemHum_buff[6] = {0x00,0x00,0x00,0x00,0x00,0x00};
bool sht30_setModeInit(void)
{
uint8_t i;
uint8_t Cmptem_humdata[6] = {0x00,0x00,0x00,0x00,0x00,0x00};
uint8_t Cmptem_humdata1[6] = {0xff,0xff,0xff,0xff,0xff,0xff};
// iic 初始化
hrs_iic_init(SH30_SDA_PIN,SH30_SCL_PIN);
delay_ms(100);
sht30_writeReg(0X88,0x30,0xA2);
sht30_writeReg(0X88,0x30,0x93);//Stop Periodic Data Acquisition Mode
Read_temHum_valu();
return false;
}
sht30 写寄存器函数
void sht30_writeReg(uint8_t dev_addr,uint8_t savHigaddr,uint8_t sav_lowaddr)
{
uint8_t send_buff[2] = {0};
send_buff[0] = savHigaddr;
send_buff[1] = sav_lowaddr;
hrs_iic_transfer(dev_addr, send_buff, 2, TWI_ISSUE_STOP);
}
sht30 写入读取寄存器函数
/*****************************************************************************
*@function name: sht30_WR_data
*@description : write and read reg
*@Para : dev_addr: device addr ;
* savHigaddr: savle hig addr;
* sav_lowaddr: savle low addr;
* rdatalen : read data len if_Rtemp_hum: set read temp_hum_mode =0,0ther reg =1
*******************************************************************************/
void sht30_WR_data(uint8_t dev_addr,uint8_t savHigaddr,uint8_t sav_lowaddr,uint8_t rdatalen,uint8_t if_Rtemp_hum)
{
uint8_t send_buff[2] = {0};
send_buff[0] = savHigaddr;
send_buff[1] = sav_lowaddr;
hrs_iic_transfer(dev_addr, send_buff, 2, TWI_DONT_ISSUE_STOP);
hrs_iic_transfer(dev_addr|0x01, TemHum_buff, rdatalen, TWI_ISSUE_STOP);
}
crc校验函数，用于检查读取数据是否正确
unsigned char crc_high_first(unsigned char *ptr, unsigned char len)
{
unsigned char i;
unsigned char crc=0xff; /* ?????crc? */
while(len--)
{
crc ^= *ptr++; /* ?????????????,????????? */
for (i=8; i>0; --i) /* ???????????????crc?? */
{
if (crc & 0x80)
crc = (crc << 1) ^ 0x31;
else
crc = (crc << 1);
}
}
return (crc);
}
读取sht30温湿度函数
void Read_temHum_valu(void)
{
uint16_t start_position;
// 寄存器函数
sht30_writeReg(0X88,0x2C,0x10);
hrs_iic_transfer(0x89, TemHum_buff, 6, TWI_ISSUE_STOP);
// 检测数据函数
if(TemHum_buff[2]!=crc_high_first(TemHum_buff,2) || TemHum_buff[5]!=crc_high_first(TemHum_buff+3,2)) return ;
// int
Temp_valu = (TemHum_buff[0]<<8|TemHum_buff[1]);
Temp_valu = ((100 * Temp_valu * 175) / 65535 - 45 * 100)/10;
Hum_valu = (TemHum_buff[3]<<8|TemHum_buff[4]);
Hum_valu = (100 * Hum_valu * 100)/65535/10;
Get_temHumValu[0] = (Temp_valu>>8); // ¸ßλΪf,¸ºÊýʱºò£¬¸ßλÊÇf
Get_temHumValu[1] = (Temp_valu);
Get_temHumValu[2] = (Hum_valu>>8);
Get_temHumValu[3] = (Hum_valu&0x0FF);
BLE_RTT("t:%d H:%d\r\n",Temp_valu,Hum_valu);
}