diff --git a/MSOS_ESP/main/CMakeLists.txt b/MSOS_ESP/main/CMakeLists.txt
index 28ab405..0a1cfe1 100644
--- a/MSOS_ESP/main/CMakeLists.txt
+++ b/MSOS_ESP/main/CMakeLists.txt
@@ -1,3 +1,3 @@
-idf_component_register(SRCS "hello_world_main.c"
-                       PRIV_REQUIRES spi_flash
-                       INCLUDE_DIRS "")
+idf_component_register(SRCS "hello_world_main.c" "iic.c" "oled.c"
+                       PRIV_REQUIRES spi_flash esp_driver_i2c log
+                       INCLUDE_DIRS ".")
diff --git a/MSOS_ESP/main/hello_world_main.c b/MSOS_ESP/main/hello_world_main.c
index 7010f3e..34fe9b0 100644
--- a/MSOS_ESP/main/hello_world_main.c
+++ b/MSOS_ESP/main/hello_world_main.c
@@ -13,6 +13,9 @@
 #include "esp_flash.h"
 #include "esp_system.h"
 
+#include "iic.h"
+#include "oled.h"
+
 void app_main(void)
 {
     printf("Hello world!\n");
@@ -42,11 +45,11 @@ void app_main(void)
 
     printf("Minimum free heap size: %" PRIu32 " bytes\n", esp_get_minimum_free_heap_size());
 
-    for (int i = 10; i >= 0; i--) {
-        printf("Restarting in %d seconds...\n", i);
+    iic_init();
+    oled_init();
+
+    while(1){
+
         vTaskDelay(1000 / portTICK_PERIOD_MS);
     }
-    printf("Restarting now.\n");
-    fflush(stdout);
-    esp_restart();
 }
diff --git a/MSOS_ESP/main/iic.c b/MSOS_ESP/main/iic.c
new file mode 100644
index 0000000..bc0bbb5
--- /dev/null
+++ b/MSOS_ESP/main/iic.c
@@ -0,0 +1,65 @@
+#include "iic.h"
+#include "driver/i2c_master.h"
+#include "esp_log.h"
+#include <stdint.h>
+
+static const char *TAG = "IIC";
+
+static i2c_master_bus_handle_t s_iic_bus = NULL;
+static i2c_master_dev_handle_t s_iic_dev = NULL;
+
+esp_err_t iic_init(void)
+{
+    i2c_master_bus_config_t bus_cfg = {
+        .i2c_port = -1,
+        .sda_io_num = (gpio_num_t)IIC_SDA_IO,
+        .scl_io_num = (gpio_num_t)IIC_SCL_IO,
+        .clk_source = I2C_CLK_SRC_DEFAULT,
+        .glitch_ignore_cnt = 7,
+        .trans_queue_depth = 0,
+        .flags.enable_internal_pullup = true,
+    };
+    esp_err_t ret = i2c_new_master_bus(&bus_cfg, &s_iic_bus);
+    if (ret != ESP_OK) {
+        ESP_LOGE(TAG, "IIC总线初始化失败");
+        return ret;
+    }
+
+    i2c_device_config_t dev_cfg = {
+        .dev_addr_length = I2C_ADDR_BIT_LEN_7,
+        .device_address = 0x00,
+        .scl_speed_hz = IIC_FREQ_HZ,
+    };
+    ret = i2c_master_bus_add_device(s_iic_bus, &dev_cfg, &s_iic_dev);
+    if (ret != ESP_OK) {
+        ESP_LOGE(TAG, "IIC总线初始化失败");
+        return ret;
+    }
+    ESP_LOGI(TAG, "IIC IO总线初始化成功");
+    return ESP_OK;
+}
+
+esp_err_t iic_send_bytes(unsigned char addr, unsigned char *txd, unsigned int len)
+{
+    if (txd == NULL || len == 0 || s_iic_dev == NULL) {
+        return ESP_ERR_INVALID_STATE;
+    }
+    esp_err_t ret = i2c_master_device_change_address(s_iic_dev, (uint16_t)addr, IIC_TIMEOUT_MS);
+    if (ret != ESP_OK) {
+        return ret;
+    }
+    return i2c_master_transmit(s_iic_dev, (const uint8_t *)txd, (size_t)len, IIC_TIMEOUT_MS);
+}
+
+unsigned char iic_read_byte(unsigned char addr)
+{
+    uint8_t byte = 0;
+    if (s_iic_dev == NULL) {
+        return 0;
+    }
+    if (i2c_master_device_change_address(s_iic_dev, (uint16_t)addr, IIC_TIMEOUT_MS) != ESP_OK) {
+        return 0;
+    }
+    i2c_master_receive(s_iic_dev, &byte, 1, IIC_TIMEOUT_MS);
+    return (unsigned char)byte;
+}
diff --git a/MSOS_ESP/main/iic.h b/MSOS_ESP/main/iic.h
new file mode 100644
index 0000000..2c8e12d
--- /dev/null
+++ b/MSOS_ESP/main/iic.h
@@ -0,0 +1,15 @@
+#ifndef IIC_H_
+#define IIC_H_
+
+#include "esp_err.h"
+
+#define IIC_SDA_IO          0
+#define IIC_SCL_IO          1
+#define IIC_FREQ_HZ         100000
+#define IIC_TIMEOUT_MS      1000
+
+esp_err_t iic_init(void);
+esp_err_t iic_send_bytes(unsigned char addr, unsigned char *txd, unsigned int len);
+unsigned char iic_read_byte(unsigned char addr);
+
+#endif
diff --git a/MSOS_ESP/main/oled.c b/MSOS_ESP/main/oled.c
new file mode 100644
index 0000000..406de7f
--- /dev/null
+++ b/MSOS_ESP/main/oled.c
@@ -0,0 +1,77 @@
+#include "oled.h"
+#include "iic.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+void oled_cmd(unsigned char IIC_Command)
+{
+    unsigned char buf[2] = {0x00, IIC_Command};
+    iic_send_bytes(OLED_ADDRESS, buf, 2);
+}
+
+void oled_dat(unsigned char IIC_Data)
+{
+    unsigned char buf[2] = {0x40, IIC_Data};
+    iic_send_bytes(OLED_ADDRESS, buf, 2);
+}
+
+void oled_set_pos(unsigned char x, unsigned char y)
+{
+    x += OLED_COL_OFFSET;
+    oled_cmd(0xb0 + 7 - y);
+    oled_cmd(((x & 0xf0) >> 4) | 0x10);
+    oled_cmd((x & 0x0f) | 0x00);
+}
+
+void oled_init_dram(char a)
+{
+    for (unsigned char y = 0; y < Y_WIDTH_; y++) {
+        oled_set_pos(0, y);
+        for (unsigned char x = 0; x < X_WIDTH; x++) {
+            oled_dat(a);
+        }
+    }
+}
+
+void oled_set_lum(unsigned char a)
+{
+    oled_cmd(0x81);
+    oled_cmd((unsigned char)(a * 255 / 100));
+}
+
+void oled_init(void)
+{
+    vTaskDelay(pdMS_TO_TICKS(200));
+
+    oled_cmd(0xAE);
+    oled_cmd(0xD5);
+    oled_cmd(0x80);
+    oled_cmd(0xA8);
+    oled_cmd(0x3F);
+    oled_cmd(0xD3);
+    oled_cmd(0x00);
+    oled_cmd(0x40);
+#if (OLED_CONTROLLER == OLED_CTRL_SH1106)
+    oled_cmd(0xAD);
+    oled_cmd(0x8B);
+#elif (OLED_CONTROLLER == OLED_CTRL_ST7315)
+    oled_cmd(0x8D);
+    oled_cmd(0x14);
+#endif
+    oled_cmd(0x20);
+    oled_cmd(0x10);
+    oled_cmd(0xA1);
+    oled_cmd(0xC0);
+    oled_cmd(0xD9);
+    oled_cmd(0xf1);
+    oled_cmd(0xDB);
+    oled_cmd(0x30);
+    oled_cmd(0xA4);
+    oled_cmd(0xA6);
+    oled_cmd(0xAF);
+
+    oled_cmd(0x81);
+    oled_cmd(0xff);
+
+    oled_init_dram(0);
+}
diff --git a/MSOS_ESP/main/oled.h b/MSOS_ESP/main/oled.h
new file mode 100644
index 0000000..4c07e95
--- /dev/null
+++ b/MSOS_ESP/main/oled.h
@@ -0,0 +1,27 @@
+#ifndef OLED_H_
+#define OLED_H_
+
+#define OLED_ADDRESS    0x3C
+#define X_WIDTH         128
+#define Y_WIDTH_        8
+
+#define OLED_CTRL_SH1106   0
+#define OLED_CTRL_ST7315   1
+#define OLED_CONTROLLER    OLED_CTRL_SH1106
+
+#if   (OLED_CONTROLLER == OLED_CTRL_SH1106)
+  #define OLED_COL_OFFSET   2
+#elif (OLED_CONTROLLER == OLED_CTRL_ST7315)
+  #define OLED_COL_OFFSET   0
+#else
+  #error "unknown OLED_CONTROLLER"
+#endif
+
+void oled_cmd(unsigned char IIC_Command);
+void oled_dat(unsigned char IIC_Data);
+void oled_set_pos(unsigned char x, unsigned char y);
+void oled_init_dram(char a);
+void oled_set_lum(unsigned char a);
+void oled_init(void);
+
+#endif