#include "stm32f10x.h"
#include "stm32f10x_rcc.h"
#include "stm32f10x_gpio.h"
#include "stm32f10x_tim.h"
#include "stm32f10x_usart.h"

//----------------
#include "stm32f10x_i2c.h"

GPIO_InitTypeDef gpio;
I2C_InitTypeDef i2c;
#define TIMER_PRESCALER 720
#define EXT_TIM_PULSE 150
#define TIM_PULSE 50

uint16_t previousState;
GPIO_InitTypeDef port;
TIM_TimeBaseInitTypeDef timer;
TIM_OCInitTypeDef timerPWM;
uint16_t buttonPreviousState;
GPIO_InitTypeDef GPIO_InitStructure;
I2C_InitTypeDef I2C_InitStructure;
void I2C_init()
{
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO, ENABLE);

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
GPIO_Init(GPIOB, &GPIO_InitStructure);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);

I2C_StructInit(&I2C_InitStructure);
I2C_InitStructure.I2C_ClockSpeed = 100000;
I2C_InitStructure.I2C_OwnAddress1 = 1;
I2C_InitStructure.I2C_Ack = I2C_Ack_Disable;//Enable
I2C_Init(I2C1, &I2C_InitStructure);
I2C_Cmd(I2C1, ENABLE);
I2C_AcknowledgeConfig(I2C1, ENABLE);
}

void I2C_single_write(uint8_t HW_address, uint8_t addr, uint8_t data)
{
I2C_GenerateSTART(I2C1, ENABLE);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C1, HW_address, I2C_Direction_Transmitter);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
I2C_SendData(I2C1, addr);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
I2C_SendData(I2C1, data);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
I2C_GenerateSTOP(I2C1, ENABLE);
while(I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY));
}

uint8_t I2C_single_read(uint8_t HW_address, uint8_t addr)
{
uint8_t data;
while(I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY));
I2C_GenerateSTART(I2C1, ENABLE);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C1, HW_address, I2C_Direction_Transmitter);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
I2C_SendData(I2C1, addr);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
I2C_GenerateSTART(I2C1, ENABLE);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C1, HW_address, I2C_Direction_Receiver);
while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_BYTE_RECEIVED));
data = I2C_ReceiveData(I2C1);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED));
I2C_AcknowledgeConfig(I2C1, DISABLE);
I2C_GenerateSTOP(I2C1, ENABLE);
while(I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY));
return data;
}

void delay(int a)
{
int i = 0;
int f = 0;
while(f < a)
{
while(i<60)
{i++;}
f++;
}
}

int main()
{
uint8_t single_data_read = 0;

I2C_init();
delay(500);
I2C_StretchClockCmd(I2C1, ENABLE);

I2C_single_write(0xA0, 0x00, 0x15);
delay(500);

single_data_read = I2C_single_read(0xA0, 0x03);

while(1);
}

void i2c_init(void)
{
    GPIO_InitTypeDef  GPIO_InitStructure;
    I2C_InitTypeDef  I2C_InitStructure;

    RCC->APB2ENR |= RCC_APB2ENR_AFIOEN;
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);

        /* I2C1 SDA and SCL configuration */
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;
        GPIO_Init(GPIOB, &GPIO_InitStructure);

        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;
        GPIO_Init(GPIOB, &GPIO_InitStructure);

     /* I2C1 configuration */
    I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
    I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
    I2C_InitStructure.I2C_OwnAddress1 = 0;
    I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
    I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
    I2C_InitStructure.I2C_ClockSpeed = 400000;//ClockSpeed;
    I2C_Cmd(I2C1, ENABLE);
    I2C_Init(I2C1, &I2C_InitStructure);
}

unsigned char I2c_Start (I2C_TypeDef* I2Cx)
{
u16 cnt = maxcnt;
if (I2Cx->SR2&I2C_SR2_BUSY) return I2C_BUS_BUSY;
I2Cx->CR1 |= I2C_CR1_START;
while ((I2Cx->SR1 & I2C_SR1_SB) == 0)
{
cnt--;
if (cnt == 0) return I2C_BUS_BUSY;
}
return 0;
}

void I2c_ReStart (I2C_TypeDef* I2Cx)
{
I2Cx->CR1 |= I2C_CR1_START;
while (!(I2Cx->SR1 & I2C_SR1_SB));
}

unsigned char I2c_WriteAddress (I2C_TypeDef* I2Cx, unsigned char i2c_address)
{
u16 cnt = maxcnt;
I2Cx->DR = i2c_address;
while (!(I2Cx->SR1 & (I2C_SR1_ADDR|I2C_SR1_ARLO|I2C_SR1_AF)))//stuck here sometimes
{
cnt--;
if (cnt == 0) return I2C_NOACK;
}
if (I2Cx->SR1&(I2C_SR1_ARLO|I2C_SR1_AF)) return I2C_NOACK;
(void) I2Cx->SR1;
(void) I2Cx->SR2;
if (i2c_address&1) while (!(I2Cx->SR1 & I2C_SR1_RXNE));
return 0;
}

void I2c_WriteByte (I2C_TypeDef* I2Cx, unsigned char data)
{
I2Cx->DR = data;
while (!(I2Cx->SR1 & I2C_SR1_BTF));
}

unsigned char I2c_ReadByte (I2C_TypeDef* I2Cx)
{
while((I2Cx->SR1 & I2C_SR1_RXNE)==0); // wait data
I2Cx->SR1;
I2Cx->SR2;
return I2Cx->DR;
}

unsigned char I2c_Stop (I2C_TypeDef* I2Cx)
{
I2Cx->CR1 |= I2C_CR1_STOP;
while (I2Cx->SR2&I2C_SR2_BUSY);
return I2C_OK;
}

void I2c_ACK (I2C_TypeDef* I2Cx)
{
I2Cx->CR1 |= I2C_CR1_ACK;
}

void I2c_NACK (I2C_TypeDef* I2Cx)
{
I2Cx->CR1 &= ~I2C_CR1_ACK;
}

/* Reads Page with 1-byte pointer */
unsigned char I2c_Read_Page (I2C_TypeDef* I2Cx, unsigned char I2c_Address, unsigned char Reg, unsigned char * buffer, unsigned char Len)
{
I2c_ACK(I2Cx);
if (I2c_Start(I2Cx)) return I2C_BUS_BUSY;
if (I2c_WriteAddress(I2Cx, I2c_Address)) return I2C_NOACK;
I2c_WriteByte(I2Cx, Reg);
I2c_ReStart(I2Cx);
I2c_WriteAddress(I2Cx, I2c_Address|1);
while (Len>1)
{
I2c_ACK(I2Cx);
* buffer++ = I2c_ReadByte(I2Cx);
Len--;
}
I2Cx->CR1&=~I2C_CR1_POS;
I2Cx->CR1 |= I2C_CR1_STOP;
* buffer++ = I2c_ReadByte(I2Cx);
//I2Cx->CR1 |= I2C_CR1_STOP;
I2c_NACK(I2Cx);
return I2C_OK;
}

unsigned char I2c_Write_Page (I2C_TypeDef* I2Cx, unsigned char I2c_Address, unsigned char Reg, unsigned char * buffer, unsigned char Len)
{
I2c_ACK(I2Cx);
if (I2c_Start(I2Cx)) return I2C_BUS_BUSY;
if (I2c_WriteAddress(I2Cx, I2c_Address)) return I2C_NOACK;
I2c_WriteByte(I2Cx, Reg);
while (Len--)
I2c_WriteByte(I2Cx, * buffer++);
I2c_Stop(I2Cx);
return I2C_OK;
}


unsigned char I2c_Write_Register (I2C_TypeDef* I2Cx, unsigned char I2c_Address, unsigned char Reg, unsigned char data)
{
if (I2c_Start(I2Cx)) return I2C_BUS_BUSY;
if (I2c_WriteAddress(I2Cx, I2c_Address)) return I2C_NOACK;
I2c_WriteByte(I2Cx, Reg);
I2c_WriteByte(I2Cx, data);
I2c_Stop(I2Cx);
return I2C_OK;
}

I2C_RESULT CheckI2C (I2C_TypeDef* I2Cx)
{
if (I2Cx->SR2&I2C_SR2_BUSY) return I2C_BUS_BUSY;
return I2C_OK;
}