说明
该模块音频传输使用5G通信频率,内部集成双向数据透传功能及低音量静音功能,I2C端口均采用GPIO模拟的方式
STM8代码
GPIO初始化
GPIO_Init(I2C_SCL_PORT, (GPIO_Pin_TypeDef)I2C_SCL_PINS, GPIO_MODE_OUT_OD_LOW_FAST); GPIO_Init(I2C_SDA_PORT, (GPIO_Pin_TypeDef)I2C_SDA_PINS, GPIO_MODE_OUT_OD_LOW_FAST);
宏定义
#define I2C_SCL_PORT (GPIOB)#define I2C_SCL_PINS (GPIO_PIN_4)#define I2C_SDA_PORT (GPIOB)#define I2C_SDA_PINS (GPIO_PIN_5)#define SDA2_IN() {GPIOB->DDR&=~(1<<(5));(GPIOB->DDR|=(0<<(5)));}#define SDA2_OUT() {GPIOB->DDR&=~(1<<(5));(GPIOB->DDR|=(1<<(5)));}#define SCL2_IN() {GPIOB->DDR&=~(1<<(4));(GPIOB->DDR|=(0<<(4)));}#define SCL2_OUT() {GPIOB->DDR&=~(1<<(4));(GPIOB->DDR|=(1<<(4)));}#define READ_SDA2 GPIO_ReadInputPin(I2C_SDA_PORT,I2C_SDA_PINS)#define READ_SCL2 GPIO_ReadInputPin(I2C_SCL_PORT,I2C_SCL_PINS)#define __delay_us(x) delay_us(x*10)#define i2c_Start() i2c_Restart()#define ev01s 0x68 #define I2C_TM_SCL_HIGH 1#define I2C_TM_SCL_LOW 3#define I2C_TM_START_HD 24#define I2C_TM_DATA_SU 5#define I2C_TM_SCL_TO_DATA 5 /* SCL low to data valid */#define I2C_TM_STOP_SU 40#define I2C_TM_SCL_TMO 10 /* clock time out */#define de_ack 0#define de_non_ack 1#define I2C_ERROR (-1)
I2C基础代码
/* * Send (re)start condition * - ensure data is high then issue a start condition * - see also i2c_Start() macro */voidi2c_Restart(void){ SCL_HIGH(); /* ensure clock is low */ SDA_HIGH(); /* ensure data is high */ __delay_us(10); SCL_LOW(); /* ensure clock is low */ SDA_HIGH(); /* ensure data is high */ __delay_us(I2C_TM_DATA_SU); SCL_HIGH(); /* clock pulse high */ __delay_us(I2C_TM_SCL_HIGH); SDA_LOW(); /* the high->low transition */ __delay_us(I2C_TM_START_HD); return; }/* * Send stop condition * - data low-high while clock high */voidi2c_Stop(void){ SCL_LOW(); SDA_LOW(); /* ensure data is low first */ __delay_us(I2C_TM_DATA_SU); SCL_HIGH(); /* float clock high */ __delay_us(I2C_TM_STOP_SU); SDA_HIGH(); /* the low->high data transistion */ return; }/* * Check for an acknowledge * - returns ack or ~ack, or ERROR if a bus error */signed chari2c_ReadAcknowledge(void){ unsigned char ack; SCL_LOW(); /* make clock is low */ __delay_us(I2C_TM_SCL_TO_DATA); /* SCL low to data out valid */ SDA_HIGH(); if(fg_i2c_ev01s) { __delay_us(50);//50 } else { __delay_us(5); } SCL_HIGH(); __delay_us(I2C_TM_DATA_SU); SDA2_IN(); //SDA设置为输入 ack = READ_SDA2; /* read the acknowledge */ SDA2_OUT(); return ack; }/* * Send a byte to the slave * - returns true on error */unsigned chari2c_SendByte(unsigned char byte){ signed char i; for(i=7; i>=0; i--) { SCL_LOW(); /* drive clock low */ if ((byte>>i)&0x01) { /* bit to send */ SDA_HIGH(); } else { SDA_LOW(); } __delay_us(3); SCL_HIGH(); __delay_us(I2C_TM_SCL_HIGH); /* clock high time */ } return FALSE; }/* * wait for the clock line to be released by slow slaves * - returns TRUE if SCL was not released after the * time out period. * - returns FALSE if and when SCL released */unsigned chari2c_WaitForSCL(void){ SCL2_IN(); /* SCL_DIR should be input here */ if(!READ_SCL2) { __delay_us(I2C_TM_SCL_TMO); /* if the clock is still low -> bus error */ if(!READ_SCL2){ SCL2_OUT(); return TRUE; } } SCL2_OUT(); return FALSE; }/* * Read a byte from the slave * - returns the byte, or I2C_ERROR if a bus error */inti2c_ReadByte(void){ unsigned char i; unsigned char byte = 0; unsigned char x; SCL_LOW(); if(fg_i2c_ev01s) { __delay_us(50);//50 } for(i=0; i<8; i++) { SCL_LOW(); /* drive clock low */ __delay_us(1); /* min clock low period */ SDA_HIGH(); /* release data line */ __delay_us(1); SCL_HIGH(); /* float clock high */ __delay_us(1); /* min clock low period */ if(i2c_WaitForSCL()) return I2C_ERROR; __delay_us(1); byte = byte << 1; /* read the next bit */ SDA2_IN(); //x=READ_SDA2&0x01; if(READ_SDA2) { x=0x01; } else { x=0x00; } SDA2_OUT(); byte |=x; } return (int)byte; }/* * send an address and data direction to the slave * - 7-bit address (lsb ignored) * - direction (FALSE = write ) */unsigned chari2c_SendAddress(unsigned char address, unsigned char rw){ return i2c_SendByte(address | (rw?1:0)); }/* * Opens communication with a device at address. mode * indicates I2C_READ or I2C_WRITE. * - returns TRUE if address is not acknowledged */unsigned chari2c_Open(unsigned char address, unsigned char mode){ i2c_Start(); i2c_SendAddress(address, mode); if(i2c_ReadAcknowledge()) return TRUE; return FALSE; }/* * Send an (~)acknowledge to the slave * - status of I2C_LAST implies this is the last byte to be sent */voidi2c_SendAcknowledge(unsigned char status){ SCL_LOW(); if ( status & 0x01) { SDA_LOW(); /* drive line low -> more to come */ }else { SDA_HIGH(); } __delay_us(I2C_TM_DATA_SU); SCL_HIGH(); /* float clock high */ __delay_us(3); return; }/* * Get a byte from the slave and acknowledges the transfer * - returns true on I2C_ERROR or byte */inti2c_GetByte(unsigned char more){ int byte; if((byte = i2c_ReadByte()) == I2C_ERROR) return I2C_ERROR; i2c_SendAcknowledge(more); return byte; }/* * Send a byte to the slave and acknowledges the transfer * - returns I2C_ERROR, ack or ~ack */signed chari2c_PutByte(unsigned char data){// if(i2c_SendByte(data))// return I2C_ERROR; i2c_SendByte(data); return i2c_ReadAcknowledge(); /* returns ack, ~ack */}void i2c_send_dada(unsigned char A,unsigned char B,unsigned char C){ disableInterrupts(); unsigned char f=5; if(fg_i2c_ev01s) { f=50; } __delay_us(f); i2c_Open(A,0); i2c_PutByte(B); i2c_PutByte(C); i2c_Stop(); enableInterrupts(); }//************************************************//* I2C check data *//************************************************void i2c_read_dada(unsigned char a,unsigned char b,unsigned char c){ unsigned char z=0; unsigned char y; unsigned char t; t=5; disableInterrupts(); if(fg_i2c_ev01s) { t=50; } __delay_us(t); i2c_Open(a,0); i2c_PutByte(b); if(a==ev01s) { i2c_Stop(); } __delay_us(t); i2c_Open(a,1); for(;z<c;z++) { y=de_non_ack; if((z+1)==c) { y=de_ack; } ev01s_rcv_buf[z]=i2c_GetByte(y); } i2c_Stop(); enableInterrupts(); }
注意:模块对i2C时序有一定要求,具体可参考数据手册
STM32代码
GPIO初始化
void IIC2_Init(void){ GPIO_InitPara GPIO_InitStructure; RCC_AHBPeriphClock_Enable(RCC_AHBPERIPH_GPIOB, ENABLE); GPIO_InitStructure.GPIO_Pin = GPIO_PIN_8 | GPIO_PIN_9; GPIO_InitStructure.GPIO_Mode = GPIO_MODE_OUT; //推挽输出 GPIO_InitStructure.GPIO_Speed = GPIO_SPEED_50MHZ; GPIO_InitStructure.GPIO_OType = GPIO_OTYPE_OD; GPIO_Init(GPIOB, &GPIO_InitStructure); GPIO_SetBits(GPIOB, GPIO_PIN_8 | GPIO_PIN_9); }/*模块接收中断,外部中断线初始化*/void ev01s_it_Init(void){ EXTI_InitPara EXTI_InitStructure; GPIO_InitPara GPIO_InitStructure; NVIC_InitPara NVIC_InitStructure; RCC_APB2PeriphClock_Enable(RCC_APB2PERIPH_CFG, ENABLE);//使能外部中断时钟 GPIO_InitStructure.GPIO_Pin = GPIO_PIN_0; GPIO_InitStructure.GPIO_Mode = GPIO_MODE_IN; //推挽输出 GPIO_InitStructure.GPIO_PuPd = GPIO_PUPD_PULLUP; GPIO_Init(GPIOB, &GPIO_InitStructure); SYSCFG_EXTILine_Config(EXTI_SOURCE_GPIOB, EXTI_SOURCE_PIN0); EXTI_InitStructure.EXTI_LINE = EXTI_LINE0; EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt; //配置中断模式 EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling; EXTI_InitStructure.EXTI_LINEEnable = ENABLE; //使能中断 EXTI_Init(&EXTI_InitStructure); NVIC_PRIGroup_Enable(NVIC_PRIGROUP_3); NVIC_InitStructure.NVIC_IRQ = EXTI0_1_IRQn; NVIC_InitStructure.NVIC_IRQPreemptPriority = 2;//优先级 NVIC_InitStructure.NVIC_IRQSubPriority = 1; NVIC_InitStructure.NVIC_IRQEnable = ENABLE; NVIC_Init(&NVIC_InitStructure); }
宏定义
//IO方向设置#define SDA2_IN() {GPIOB->CTLR&=~(3<<(9*2));GPIOB->CTLR|=0<<9*2;} #define SDA2_OUT() {GPIOB->CTLR&=~(3<<(9*2));GPIOB->CTLR|=1<<9*2;}#define SCL2_IN() {GPIOB->CTLR&=~(3<<(8*2));GPIOB->CTLR|=0<<8*2;} #define SCL2_OUT() {GPIOB->CTLR&=~(3<<(8*2));GPIOB->CTLR|=1<<8*2;}//IO操作函数#define IIC2_SCL(x) (x==0)?GPIO_ResetBits(GPIOB, GPIO_PIN_8):GPIO_SetBits(GPIOB, GPIO_PIN_8)// PBout(8) //SCL#define IIC2_SDA(x) (x==0)?GPIO_ResetBits(GPIOB, GPIO_PIN_9):GPIO_SetBits(GPIOB, GPIO_PIN_9)// PBout(9) //SDA #define READ_SDA2 GPIO_ReadInputBit(GPIOB,GPIO_PIN_9)//PBin(9) //输入SDA#define READ_SCL2 GPIO_ReadInputBit(GPIOB,GPIO_PIN_8)//PBin(8) //输入SCL#define SCL_LOW() IIC2_SCL(0)#define SCL_HIGH() IIC2_SCL(1)#define SDA_HIGH() IIC2_SDA(1)#define SDA_LOW() IIC2_SDA(0)#define ev01s 0x68 #define I2C_TM_SCL_HIGH 1#define I2C_TM_SCL_LOW 3#define I2C_TM_START_HD 24#define I2C_TM_DATA_SU 5#define I2C_TM_SCL_TO_DATA 5 /* SCL low to data valid */#define I2C_TM_STOP_SU 40#define I2C_TM_SCL_TMO 10 /* clock time out */#define de_ack 0#define de_non_ack 1#define I2C_ERROR (-1)#define __delay_us(x) delay_us(x*10)#define i2c_Start() i2c_Restart()
作者:WangDaS
链接:https://www.jianshu.com/p/1dee046878ad
点击查看更多内容
为 TA 点赞
评论
共同学习,写下你的评论
评论加载中...
作者其他优质文章
正在加载中
感谢您的支持,我会继续努力的~
扫码打赏,你说多少就多少
赞赏金额会直接到老师账户
支付方式
打开微信扫一扫,即可进行扫码打赏哦