实验目的

1.使用PSoc62™芯片读取内部rtc时间

2.OLED屏幕显示当前时间戳

实验准备

• PSoc62™开发板
• SSD1306 OLED模块
• 公母头杜邦线

芯片资源

PSoC 6系列MCU时钟系统由以下几部分组成，PSoc62™开发板没有接外部时钟源，所以只能从IMO、ILO、PILO里边配置

• 三个内部的时钟源
  • 8-MHz internal main oscillator (IMO)
  • 32-kHz internal low-speed oscillator (ILO)
  • Precision 32-kHz internal low-speed oscillator (PILO)
• 三个外部的时钟源
  • External clock (EXTCLK) generated using a signal from an I/O pin
  • External 16–35 MHz crystal oscillator (ECO)
  • External 32-kHz watch crystal oscillator (WCO)

组件配置

rtc配置，这里的RTC_USING_LSI指的是ILO

使能u8g2软件包，这里使用软件的方式模拟i2c时序

注意要在代码里边绑定i2c引脚，pin number和GPIO的对应关系：P8.0 : 8 x 8 = 64，P8.1 : 8 x 8 + 1 = 65

#define OLED_I2C_PIN_SCL                    64  // P8.0
#define OLED_I2C_PIN_SDA                    65  // P8.1

模块电路

GPIO引脚

MCU_ARD_SCL -> P8.0

MCU_ARD_SDA -> P8.1

模块连接图

右侧排母从上往下第1、2引脚分别对应SCL、SDA

实物连接

依次连接OLED模块的VCC、GND、SDL、SDA引脚

程序设计

Infineon PSoc™62时钟源设置代码

#ifdef   BSP_RTC_USING_LSE
    Cy_RTC_SelectClockSource(CY_RTC_CLK_SELECT_WCO);
#else
    Cy_RTC_SelectClockSource(CY_RTC_CLK_SELECT_ILO);
#endif

由于RT-Thread HAL_Drivers不太完善，这里需要修改RTC HAL层的代码，把上面的代码添加到rt_hw_rtc_init里边去

static int rt_hw_rtc_init(void)
{
    rt_err_t result = RT_EOK;

    ifx32_rtc_dev.ops = &_rtc_ops;

    if (rt_hw_rtc_register(&ifx32_rtc_dev, "rtc", RT_DEVICE_FLAG_RDWR, RT_NULL) != RT_EOK)
    {
        LOG_E("rtc init failed");
        result = -RT_ERROR;
    }
    else
    {
        LOG_D("rtc init success");
    }

#ifdef   BSP_RTC_USING_LSE
    Cy_RTC_SelectClockSource(CY_RTC_CLK_SELECT_WCO);
#else
    Cy_RTC_SelectClockSource(CY_RTC_CLK_SELECT_ILO);
#endif
    if (cyhal_rtc_init(&rtc_obj) != RT_EOK)
    {
        LOG_E("rtc init failed.");
        return -RT_ERROR;
    }

    return RT_EOK;


    return result;
}

OLED驱动，读取当前系统时间戳并显示到屏幕

void oled_display()
{
    time_t now;
    struct tm *p_tm;
    u8g2_t u8g2;
    char buffer[50];

    // Initialization
    u8g2_Setup_ssd1306_i2c_128x64_noname_f( &u8g2, U8G2_R0, u8x8_byte_sw_i2c, u8x8_gpio_and_delay_rtthread);
    u8x8_SetPin(u8g2_GetU8x8(&u8g2), U8X8_PIN_I2C_CLOCK, OLED_I2C_PIN_SCL);
    u8x8_SetPin(u8g2_GetU8x8(&u8g2), U8X8_PIN_I2C_DATA, OLED_I2C_PIN_SDA);

    u8g2_InitDisplay(&u8g2);
    u8g2_SetPowerSave(&u8g2, 0);

    // Draw Graphics
    /* full buffer example, setup procedure ends in _f */
    u8g2_ClearBuffer(&u8g2);
    u8g2_SetFont(&u8g2, u8g2_font_ncenB08_tr);
    u8g2_DrawStr(&u8g2, 1, 18, "U8g2 on RT-Thread");
    u8g2_SendBuffer(&u8g2);

    u8g2_SetFont(&u8g2, u8g2_font_unifont_t_symbols);
    u8g2_DrawGlyph(&u8g2, 112, 56, 0x2603 );
    u8g2_SendBuffer(&u8g2);

    for (;;)
    {
        u8g2_ClearBuffer(&u8g2);
        u8g2_SetFont(&u8g2, u8g2_font_ncenB08_tr);
        now = time(RT_NULL);
        p_tm = localtime(&now);
        memset(buffer, 0, 50);
        snprintf(buffer, 50, "%d-%d-%d %d:%d:%d\n", p_tm->tm_year+ 1900, p_tm->tm_mon + 1, p_tm->tm_mday, p_tm->tm_hour, p_tm->tm_min, p_tm->tm_sec);
        u8g2_DrawStr(&u8g2, 1, 18, buffer);
        u8g2_SendBuffer(&u8g2);
        rt_thread_mdelay(1000);
    }
}

整合代码

#include <rtthread.h>
#include <rtdevice.h>
#include <time.h>
#include "drv_gpio.h"
#include "drivers/alarm.h"
#include <rtdbg.h>
#include <u8g2_port.h>

#define OLED_I2C_PIN_SCL                    64  // P8.0
#define OLED_I2C_PIN_SDA                    65  // P8.1

#define RTC_NAME "rtc"

static rt_device_t device = RT_NULL;

static int uesr_rtc_init(void)
{
    rt_err_t ret = RT_EOK;
    time_t now;

    device = rt_device_find(RTC_NAME);
    if (!device)
    {
        rt_kprintf("find %s failed!", RTC_NAME);
        return RT_ERROR;
    }

    if(rt_device_open(device, 0) != RT_EOK)
    {
        rt_kprintf("open %s failed!", RTC_NAME);
        return RT_ERROR;
    }

    ret = set_date(2024, 1, 20);
    if (ret != RT_EOK)
    {
        rt_kprintf("set RTC date failed\n");
        return ret;
    }

    ret = set_time(16, 55, 50);
    if (ret != RT_EOK)
    {
        rt_kprintf("set RTC time failed\n");
        return ret;
    }

    now = time(RT_NULL);
    rt_kprintf("RTC device init success,now time is %s\n", ctime(&now));

    return ret;
}

INIT_APP_EXPORT(uesr_rtc_init);

void oled_display()
{
    time_t now;
    struct tm *p_tm;
    u8g2_t u8g2;
    char buffer[50];

    // Initialization
    u8g2_Setup_ssd1306_i2c_128x64_noname_f( &u8g2, U8G2_R0, u8x8_byte_sw_i2c, u8x8_gpio_and_delay_rtthread);
    u8x8_SetPin(u8g2_GetU8x8(&u8g2), U8X8_PIN_I2C_CLOCK, OLED_I2C_PIN_SCL);
    u8x8_SetPin(u8g2_GetU8x8(&u8g2), U8X8_PIN_I2C_DATA, OLED_I2C_PIN_SDA);

    u8g2_InitDisplay(&u8g2);
    u8g2_SetPowerSave(&u8g2, 0);

    // Draw Graphics
    /* full buffer example, setup procedure ends in _f */
    u8g2_ClearBuffer(&u8g2);
    u8g2_SetFont(&u8g2, u8g2_font_ncenB08_tr);
    u8g2_DrawStr(&u8g2, 1, 18, "U8g2 on RT-Thread");
    u8g2_SendBuffer(&u8g2);

    u8g2_SetFont(&u8g2, u8g2_font_unifont_t_symbols);
    u8g2_DrawGlyph(&u8g2, 112, 56, 0x2603 );
    u8g2_SendBuffer(&u8g2);

    for (;;)
    {
        u8g2_ClearBuffer(&u8g2);
        u8g2_SetFont(&u8g2, u8g2_font_ncenB08_tr);
        now = time(RT_NULL);
        p_tm = localtime(&now);
        memset(buffer, 0, 50);
        snprintf(buffer, 50, "%d-%d-%d %d:%d:%d\n", p_tm->tm_year+ 1900, p_tm->tm_mon + 1, p_tm->tm_mday, p_tm->tm_hour, p_tm->tm_min, p_tm->tm_sec);
        u8g2_DrawStr(&u8g2, 1, 18, buffer);
        u8g2_SendBuffer(&u8g2);
        rt_thread_mdelay(1000);
    }
}

int main(void)
{
    oled_display();
    return 0;
}

实验效果

在msh终端敲命令date，即可查看开发板rtc时间

同时OLED模块实时显示当前时间