NRF52832模拟IIC

NRF52832没有内置模拟IIC，但可以使用软件模拟实现。以下是一个简单的软件模拟IIC实现代码示例：

#include "nrf_gpio.h"
#include "nrf_delay.h"

#define SDA_PIN  5
#define SCL_PIN  6

#define SDA_HIGH() nrf_gpio_pin_set(SDA_PIN)
#define SDA_LOW() nrf_gpio_pin_clear(SDA_PIN)
#define SCL_HIGH() nrf_gpio_pin_set(SCL_PIN)
#define SCL_LOW() nrf_gpio_pin_clear(SCL_PIN)
#define SDA_READ() nrf_gpio_pin_read(SDA_PIN)

void iic_start(void)
{
    SDA_HIGH();
    SCL_HIGH();
    nrf_delay_us(5);
    SDA_LOW();
    nrf_delay_us(5);
    SCL_LOW();
}

void iic_stop(void)
{
    SDA_LOW();
    SCL_HIGH();
    nrf_delay_us(5);
    SDA_HIGH();
    nrf_delay_us(5);
}

uint8_t iic_write_byte(uint8_t data)
{
    uint8_t i, ack;
    for (i = 0; i < 8; i++) {
        if (data & 0x80) {
            SDA_HIGH();
        } else {
            SDA_LOW();
        }
        nrf_delay_us(5);
        SCL_HIGH();
        nrf_delay_us(5);
        SCL_LOW();
        data <<= 1;
    }
    SDA_HIGH();
    nrf_delay_us(5);
    SCL_HIGH();
    nrf_delay_us(5);
    ack = SDA_READ();
    SCL_LOW();
    return ack;
}

uint8_t iic_read_byte(uint8_t ack)
{
    uint8_t i, data = 0;
    SDA_HIGH();
    for (i = 0; i < 8; i++) {
        nrf_delay_us(5);
        SCL_HIGH();
        nrf_delay_us(5);
        data <<= 1;
        if (SDA_READ()) {
            data |= 0x01;
        }
        SCL_LOW();
    }
    if (ack) {
        SDA_LOW();
    } else {
        SDA_HIGH();
    }
    nrf_delay_us(5);
    SCL_HIGH();
    nrf_delay_us(5);
    SCL_LOW();
    SDA_HIGH();
    return data;
}

使用示例：

iic_start();
iic_write_byte(0x3C << 1);
iic_write_byte(0x00);
iic_stop();

iic_start();
iic_write_byte(0x3C << 1 | 0x01);
uint8_t data = iic_read_byte(0);
iic_stop();