IIC EEPROM Driver Usage Instructions

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Introduction

This example demonstrates how to use the RT-Thread I2C framework on the EtherKit to perform read and write operations on the onboard EEPROM.

Hardware Description

The EEPROM used on the EtherKit is an AT24C16, which is connected to the I2C0 of the R9A07G084M08GBG chip.

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FSP Configuration Instructions

Create a new stack and select r_iic_master. Then, configure the I2C0 settings as shown below:

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RT-Thread Settings Configuration

Enable the RT-Thread I2C driver framework and the AT24C16 driver software package in the configuration.

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Example Project Description

The example uses the AT24C16 driver package to perform read and write operations at EEPROM addresses 0x00 and 0x20.

#ifdef PKG_USING_AT24CXX
#include "at24cxx.h"
#define EEPROM_I2C_NAME "i2c0"
static at24cxx_device_t at24c02_dev;
static void eeprom_test(void)
{
    char str1[] = "test string-hello rtthread\n";
    char str2[] = "test string-rzt2m eeprom testcase\n";
    uint8_t read_buffer1[50];
    uint8_t read_buffer2[50];
    at24c02_dev = at24cxx_init(EEPROM_I2C_NAME, 0x0);
    if (at24c02_dev == RT_NULL)
    {
        rt_kprintf("eeprom init failed\n");
        return;
    }
    rt_memset(read_buffer1, 0x0, sizeof(read_buffer1));
    rt_memset(read_buffer2, 0x0, sizeof(read_buffer2));
    at24cxx_write(at24c02_dev, 0x0, (uint8_t *)str1, (sizeof(str1) - 1));
    rt_kprintf("write eeprom data to 0x0: %s\n", str1);
    rt_thread_mdelay(1000);
    at24cxx_read(at24c02_dev, 0x0, read_buffer1, (sizeof(str1) - 1));
    rt_kprintf("read eeprom data from 0x0: %s\n", read_buffer1);
    at24cxx_write(at24c02_dev, 0x20, (uint8_t *)str2, (sizeof(str2) - 1));
    rt_kprintf("write eeprom data to 0x20: %s\n", str2);
    rt_thread_mdelay(1000);
    at24cxx_read(at24c02_dev, 0x20, read_buffer2, (sizeof(str2) - 1));
    rt_kprintf("read eeprom data from 0x20: %s\n", read_buffer2);
    if (rt_strcmp((const char *)str1, (const char *)read_buffer1) != 0 && rt_strcmp((const char *)str2, (const char *)read_buffer2) != 0)
        rt_kprintf("eeprom test fail\n");
    else
        rt_kprintf("eeprom test success\n");
    at24cxx_deinit(at24c02_dev);
}
MSH_CMD_EXPORT(eeprom_test, eeprom test sample);
#endif

Compilation & Download

  • RT-Thread Studio: In RT-Thread Studio’s package manager, download the EtherKit resource package, create a new project, and compile it.

  • IAR: First, double-click mklinks.bat to create symbolic links between RT-Thread and the libraries folder. Then, use the Env tool to generate the IAR project. Finally, double-click project.eww to open the IAR project and compile it.

After compilation, connect the development board’s JLink interface to the PC and download the firmware to the development board.

Run Effect

To test the EEPROM, enter the eeprom_test command in the serial terminal:

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