/*!
    \file  main.c
    \brief master receiver and slave transmitter interrupt
*/

/*
    Copyright (C) 2017 GigaDevice

    2017-06-06, V1.0.0, firmware for GD32F3x0
*/

#include "gd32f3x0.h"
#include "I2C_IE.h"
#include "gd32f3x0_eval.h"

uint8_t i2c_buffer_transmitter[16];
uint8_t i2c_buffer_receiver[16];

volatile uint8_t*       i2c_txbuffer;
volatile uint8_t*       i2c_rxbuffer;
volatile uint16_t       I2C_nBytes;
volatile ErrStatus      status;
ErrStatus state = ERROR;

void rcu_config(void);
void gpio_config(void);
void i2c_config(void);
void i2c_nvic_config(void);
ErrStatus memory_compare(uint8_t* src, uint8_t* dst, uint16_t length);

/*!
    \brief      main function
    \param[in]  none
    \param[out] none
    \retval     none
*/
int main(void)
{
    int i;
    
    /* initialize LED1, LED2, as the transfer instruction */
    gd_eval_led_init(LED1);
    gd_eval_led_init(LED2);
    rcu_config();
    gpio_config();
    i2c_config();
    i2c_nvic_config();

    for(i=0; i<16; i++){
        i2c_buffer_transmitter[i] = i + 0x80;
    }
     /* initialize i2c_txbuffer, i2c_rxbuffer, I2C_nBytes and status */
    i2c_txbuffer = i2c_buffer_transmitter;
    i2c_rxbuffer = i2c_buffer_receiver;
    I2C_nBytes = 16;
    status = ERROR;
    
    /* enable the I2C0 interrupt */
    i2c_interrupt_enable(I2C0, I2C_INT_ERR | I2C_INT_BUF | I2C_INT_EV);
    /* enable the I2C1 interrupt */
    i2c_interrupt_enable(I2C1, I2C_INT_ERR | I2C_INT_BUF | I2C_INT_EV);
    if(2 == I2C_nBytes){
        /* send ACK for the next byte */
        i2c_ackpos_config(I2C0, I2C_ACKPOS_NEXT);
    }
    /* the master waits until the I2C bus is idle */
    while(i2c_flag_get(I2C0, I2C_FLAG_I2CBSY));
    /* the master sends a start condition to I2C bus */
    i2c_start_on_bus(I2C0);
    
    while(I2C_nBytes>0);
    while(SUCCESS != status);
    /* if the transfer is successfully completed, LED1 and LED2 is on */
    state = memory_compare(i2c_buffer_transmitter, i2c_buffer_receiver, 16);
    if(SUCCESS == state){
        /* if success, LED1 and LED2 are on */
        gd_eval_led_on(LED1);
        gd_eval_led_on(LED2);
    }else{
        /* if failed, LED1 and LED2 are off */
        gd_eval_led_off(LED1);
        gd_eval_led_off(LED2); 
    } 
    while(1)
    {}
}

/*!
    \brief      memory compare function
    \param[in]  src : source data
    \param[in]  dst : destination data
    \param[in]  length : the compare data length
    \param[out] none
    \retval     ErrStatus : ERROR or SUCCESS
*/
ErrStatus memory_compare(uint8_t* src, uint8_t* dst, uint16_t length) 
{
    while(length--){
        if(*src++ != *dst++){
            return ERROR;
        }
    }
    return SUCCESS;
}

/*!
    \brief      enable the peripheral clock
    \param[in]  none
    \param[out] none
    \retval     none
*/
void rcu_config(void)
{
    /* enable GPIOB clock */
    rcu_periph_clock_enable(RCU_GPIOB);
    /* enable I2C1 clock */
    rcu_periph_clock_enable(RCU_I2C1);
    /* enable I2C0 clock */
    rcu_periph_clock_enable(RCU_I2C0);
}

/*!
    \brief      cofigure the GPIO ports
    \param[in]  none
    \param[out] none
    \retval     none
*/
void gpio_config(void)
{
    /* connect PB6 to I2C0_SCL */
    gpio_af_set(GPIOB, GPIO_AF_1, GPIO_PIN_6);
    /* connect PB7 to I2C0_SDA */
    gpio_af_set(GPIOB, GPIO_AF_1, GPIO_PIN_7);
    /* connect PB10 to I2C1_SCL */
    gpio_af_set(GPIOB, GPIO_AF_1, GPIO_PIN_10);
    /* connect PB11 to I2C1_SDA */
    gpio_af_set(GPIOB, GPIO_AF_1, GPIO_PIN_11);
    /* configure GPIO pins of I2C0 */
    gpio_mode_set(GPIOB, GPIO_MODE_AF, GPIO_PUPD_PULLUP,GPIO_PIN_6);
    gpio_output_options_set(GPIOB, GPIO_OTYPE_OD, GPIO_OSPEED_50MHZ,GPIO_PIN_6);
    gpio_mode_set(GPIOB, GPIO_MODE_AF, GPIO_PUPD_PULLUP,GPIO_PIN_7);
    gpio_output_options_set(GPIOB, GPIO_OTYPE_OD, GPIO_OSPEED_50MHZ,GPIO_PIN_7);
    /* configure GPIO pins of I2C1 */
    gpio_mode_set(GPIOB, GPIO_MODE_AF, GPIO_PUPD_PULLUP,GPIO_PIN_10);
    gpio_output_options_set(GPIOB, GPIO_OTYPE_OD, GPIO_OSPEED_50MHZ,GPIO_PIN_10);
    gpio_mode_set(GPIOB, GPIO_MODE_AF, GPIO_PUPD_PULLUP,GPIO_PIN_11);
    gpio_output_options_set(GPIOB, GPIO_OTYPE_OD, GPIO_OSPEED_50MHZ,GPIO_PIN_11);
}

/*!
    \brief      cofigure the I2C0 and I2C1 interfaces
    \param[in]  none
    \param[out] none
    \retval     none
*/
void i2c_config(void)
{
    /* I2C clock configure */
    i2c_clock_config(I2C0, 100000, I2C_DTCY_2);
    /* I2C address configure */
    i2c_mode_addr_config(I2C0, I2C_I2CMODE_ENABLE, I2C_ADDFORMAT_7BITS, I2C0_SLAVE_ADDRESS7);
    /* enable I2C0 */
    i2c_enable(I2C0);
    /* enable acknowledge */
    i2c_ack_config(I2C0, I2C_ACK_ENABLE);
    i2c_clock_config(I2C1, 100000, I2C_DTCY_2);
    /* I2C address configure */
    i2c_mode_addr_config(I2C1, I2C_I2CMODE_ENABLE, I2C_ADDFORMAT_7BITS, I2C1_SLAVE_ADDRESS7);
    /* enable I2C1 */
    i2c_enable(I2C1);
    /* enable acknowledge */
    i2c_ack_config(I2C1, I2C_ACK_ENABLE);
}

/*!
    \brief      cofigure the NVIC peripheral
    \param[in]  none
    \param[out] none
    \retval     none
*/
void i2c_nvic_config(void)
{
    nvic_priority_group_set(NVIC_PRIGROUP_PRE1_SUB3);
    nvic_irq_enable(I2C0_EV_IRQn, 0, 3);
    nvic_irq_enable(I2C1_EV_IRQn, 0, 4);
    nvic_irq_enable(I2C0_ER_IRQn, 0, 2);
    nvic_irq_enable(I2C1_ER_IRQn, 0, 1);
}