diff --git a/sdk/examples/spi_master/flash_n25q.c b/sdk/examples/spi_master/flash_n25q.c
index 68a95ca..cd4fda8 100644
--- a/sdk/examples/spi_master/flash_n25q.c
+++ b/sdk/examples/spi_master/flash_n25q.c
@@ -13,6 +13,8 @@
  * 5.擦除的最小单位是子扇区，编程(写)的最小单位是页，读的最小单位是字节
  */
 
+static uint8_t current_spi_mode;
+
 
 void flash_n25q_init(uint16_t clk_div)
 {
@@ -25,6 +27,8 @@ void flash_n25q_init(uint16_t clk_div)
     spi0_set_ss_level(1);
     spi0_set_ss_ctrl_by_sw(1);
     spi0_set_enable(1);
+
+    current_spi_mode = SPI_MODE_STANDARD;
 }
 
 // 写使能
@@ -86,12 +90,16 @@ uint8_t flash_n25q_is_busy()
 
 // 读数据
 // addr: 0, 1, 2, ...
-void flash_n25q_read_data(uint8_t data[], uint32_t len, uint32_t addr)
+void flash_n25q_read(uint8_t data[], uint32_t len, uint32_t addr)
 {
-    uint8_t cmd;
+    uint8_t cmd, i;
     uint8_t tran_addr[3];
 
-    cmd = CMD_READ;
+    if (current_spi_mode == SPI_MODE_STANDARD)
+        cmd = CMD_READ;
+    else
+        cmd = CMD_FAST_READ;
+
     tran_addr[0] = (addr >> 16) & 0xff;
     tran_addr[1] = (addr >> 8)  & 0xff;
     tran_addr[2] = (addr >> 0)  & 0xff;
@@ -99,6 +107,11 @@ void flash_n25q_read_data(uint8_t data[], uint32_t len, uint32_t addr)
     spi0_set_ss_level(0);
     spi0_master_write_bytes(&cmd, 1);
     spi0_master_write_bytes(tran_addr, 3);
+    if (current_spi_mode != SPI_MODE_STANDARD) {
+        for (i = 0; i < (DUMMY_CNT >> 1); i++)
+            spi0_master_read_bytes(data, 1);
+        spi0_reset_rxfifo();
+    }
     spi0_master_read_bytes(data, len);
     spi0_set_ss_level(1);
 }
@@ -208,6 +221,11 @@ void flash_n25q_enable_quad_mode(uint8_t en)
     flash_n25q_write_enhanced_volatile_conf_reg(data);
 
     flash_n25q_write_enable(0);
+
+    if (en)
+        current_spi_mode = SPI_MODE_QUAD;
+    else
+        current_spi_mode = SPI_MODE_STANDARD;
 }
 
 // 设置n25q dummy cycles
@@ -225,56 +243,17 @@ void flash_n25q_set_dummy_clock_cycles(uint8_t num)
     flash_n25q_write_enable(0);
 }
 
-void flash_n25q_quad_output_fast_read(uint32_t addr, uint8_t data[], uint32_t len)
-{
-    uint8_t tran_addr[3];
-    uint8_t cmd, i;
-
-    cmd = CMD_QUAD_OUTPUT_FAST_READ;
-
-    tran_addr[0] = (addr >> 16) & 0xff;
-    tran_addr[1] = (addr >> 8)  & 0xff;
-    tran_addr[2] = (addr >> 0)  & 0xff;
-
-    spi0_set_ss_level(0);
-    spi0_master_write_bytes(&cmd, 1);
-    spi0_master_write_bytes(tran_addr, 3);
-    for (i = 0; i < (DUMMY_CNT >> 1); i++)
-        spi0_master_read_bytes(data, 1);
-    spi0_reset_rxfifo();
-    spi0_master_read_bytes(data, len);
-    spi0_set_ss_level(1);
-}
-
-// 标准SPI模式读flash ID
+// 读flash ID
 n25q_id_t flash_n25q_read_id()
 {
     n25q_id_t id;
     uint8_t cmd;
     uint8_t data[3];
 
-    cmd = CMD_READ_ID;
-
-    spi0_set_ss_level(0);
-    spi0_master_write_bytes(&cmd, 1);
-    spi0_master_read_bytes(data, 3);
-    spi0_set_ss_level(1);
-
-    id.manf_id = data[0];
-    id.mem_type = data[1];
-    id.mem_cap = data[2];
-
-    return id;
-}
-
-// DUAL/QUAD SPI模式读flash ID
-n25q_id_t flash_n25q_multi_io_read_id()
-{
-    n25q_id_t id;
-    uint8_t cmd;
-    uint8_t data[3];
-
-    cmd = CMD_MULTI_IO_READ_ID;
+    if (current_spi_mode == SPI_MODE_STANDARD)
+        cmd = CMD_READ_ID;
+    else
+        cmd = CMD_MULTI_IO_READ_ID;
 
     spi0_set_ss_level(0);
     spi0_master_write_bytes(&cmd, 1);
diff --git a/sdk/examples/spi_master/flash_n25q.h b/sdk/examples/spi_master/flash_n25q.h
index c12040f..4a24910 100644
--- a/sdk/examples/spi_master/flash_n25q.h
+++ b/sdk/examples/spi_master/flash_n25q.h
@@ -13,7 +13,6 @@
 #define CMD_READ 					        (0x03)
 #define CMD_FAST_READ                       (0x0b)
 #define CMD_QUAD_OUTPUT_FAST_READ           (0x6b)
-#define CMD_4_4_4_FAST_READ                 (0xeb)
 #define CMD_WRITE_DISABLE 			        (0x04)
 #define CMD_READ_STATUS_REG 		        (0x05)
 #define CMD_WRITE_ENABLE 			        (0x06)
@@ -32,7 +31,6 @@
 #define CMD_WRITE_VOL_CONF_REG              (0x81)
 #define CMD_READ_NONVOL_CONF_REG            (0xB5)
 
-
 #define DUMMY_CNT                           (0xa)
 
 
@@ -44,13 +42,12 @@ typedef struct {
 
 void flash_n25q_init(uint16_t clk_div);
 n25q_id_t flash_n25q_read_id();
-n25q_id_t flash_n25q_multi_io_read_id();
 void flash_n25q_write_enable(uint8_t en);
 uint8_t flash_n25q_read_reg(uint8_t cmd);
 void flash_n25q_write_reg(uint8_t cmd, uint8_t data);
 uint8_t flash_n25q_read_status_reg();
 uint8_t flash_n25q_is_busy();
-void flash_n25q_read_data(uint8_t data[], uint32_t len, uint32_t addr);
+void flash_n25q_read(uint8_t data[], uint32_t len, uint32_t addr);
 void flash_n25q_subsector_erase(uint32_t subsector);
 void flash_n25q_sector_erase(uint32_t sector);
 void flash_n25q_page_program(uint8_t data[], uint32_t len, uint32_t page);
@@ -58,7 +55,6 @@ uint8_t flash_n25q_read_enhanced_volatile_conf_reg();
 void flash_n25q_write_enhanced_volatile_conf_reg(uint8_t data);
 void flash_n25q_enable_quad_mode(uint8_t en);
 void flash_n25q_set_dummy_clock_cycles(uint8_t num);
-void flash_n25q_quad_output_fast_read(uint32_t addr, uint8_t data[], uint32_t len);
 uint8_t flash_n25q_read_nonvolatile_conf_reg();
 
 #endif
diff --git a/sdk/examples/spi_master/main.c b/sdk/examples/spi_master/main.c
index 6374cde..e487664 100644
--- a/sdk/examples/spi_master/main.c
+++ b/sdk/examples/spi_master/main.c
@@ -16,13 +16,90 @@ uint8_t program_data[BUFFER_SIZE];
 uint8_t read_data[BUFFER_SIZE];
 
 
-int main()
+static void standard_spi_test()
 {
     uint16_t i;
     n25q_id_t id;
 
+    xprintf("Standard SPI test started...\n");
+
+    id = flash_n25q_read_id();
+    xprintf("manf id = 0x%2x\n", id.manf_id);
+    xprintf("mem type = 0x%2x\n", id.mem_type);
+    xprintf("mem cap = 0x%2x\n", id.mem_cap);
+
+    // 初始化要编程的数据
+    for (i = 0; i < BUFFER_SIZE; i++)
+        program_data[i] = i;
+
+    // 擦除第0个子扇区
+    flash_n25q_subsector_erase(0);
+    xprintf("program data: \n");
+    // 打印读出来的数据
+    for (i = 0; i < BUFFER_SIZE; i++)
+        xprintf("0x%x\n", program_data[i]);
+    // 编程第1页
+    flash_n25q_page_program(program_data, BUFFER_SIZE, 1);
+    // 读第1页
+    flash_n25q_read(read_data, BUFFER_SIZE, N25Q_PAGE_TO_ADDR(1));
+    xprintf("read data: \n");
+    // 打印读出来的数据
+    for (i = 0; i < BUFFER_SIZE; i++)
+        xprintf("0x%x\n", read_data[i]);
+
+    xprintf("Standard SPI test end...\n");
+}
+
+static void quad_spi_test()
+{
+    uint16_t i;
+    n25q_id_t id;
+
+    xprintf("\nQuad SPI test started...\n");
+
+    flash_n25q_set_dummy_clock_cycles(DUMMY_CNT);
+    // 使能N25Q QSPI模式
+    flash_n25q_enable_quad_mode(1);
+    // 使能SPI控制器QSPI模式
+    spi0_set_spi_mode(SPI_MODE_QUAD);
+
+    id = flash_n25q_read_id();
+    xprintf("manf id = 0x%2x\n", id.manf_id);
+    xprintf("mem type = 0x%2x\n", id.mem_type);
+    xprintf("mem cap = 0x%2x\n", id.mem_cap);
+
+    // 初始化要编程的数据
+    for (i = 0; i < BUFFER_SIZE; i++)
+        program_data[i] = i;
+
+    // 擦除第1个子扇区
+    flash_n25q_subsector_erase(1);
+    xprintf("program data: \n");
+    // 打印读出来的数据
+    for (i = 0; i < BUFFER_SIZE; i++)
+        xprintf("0x%x\n", program_data[i]);
+    // 编程第16页
+    flash_n25q_page_program(program_data, BUFFER_SIZE, 16);
+    // 读第16页
+    flash_n25q_read(read_data, BUFFER_SIZE, N25Q_PAGE_TO_ADDR(16));
+    xprintf("read data: \n");
+    // 打印读出来的数据
+    for (i = 0; i < BUFFER_SIZE; i++)
+        xprintf("0x%x\n", read_data[i]);
+
+    // 失能N25Q QSPI模式
+    flash_n25q_enable_quad_mode(0);
+    spi0_set_spi_mode(SPI_MODE_STANDARD);
+
+    xprintf("Quad SPI test end...\n");
+}
+
+int main()
+{
+    // UART引脚配置
     pinmux_set_io0_func(IO0_UART0_TX);
     pinmux_set_io3_func(IO3_UART0_RX);
+    // SPI引脚配置
     pinmux_set_io10_func(IO10_SPI_CLK);
     pinmux_set_io11_func(IO11_SPI_SS);
     pinmux_set_io12_func(IO12_SPI_DQ0);
@@ -33,51 +110,8 @@ int main()
     uart0_init(uart0_putc);
     flash_n25q_init(5);
 
-    xprintf("read ID through standard SPI mode\n");
-    id = flash_n25q_read_id();
-    xprintf("manf id = 0x%2x\n", id.manf_id);
-    xprintf("mem type = 0x%2x\n", id.mem_type);
-    xprintf("mem cap = 0x%2x\n", id.mem_cap);
-
-    // 初始化要编程的数据
-    for (i = 0; i < BUFFER_SIZE; i++)
-        program_data[i] = i;
-
-    xprintf("start erase subsector...\n");
-    // 擦除第0个子扇区
-    flash_n25q_subsector_erase(0x00);
-    xprintf("start program page...\n");
-    xprintf("program data: \n");
-    // 打印读出来的数据
-    for (i = 0; i < BUFFER_SIZE; i++)
-        xprintf("0x%x\n", program_data[i]);
-    // 编程第1页
-    flash_n25q_page_program(program_data, BUFFER_SIZE, 0x01);
-    xprintf("start read page...\n");
-    // 读第1页
-    flash_n25q_read_data(read_data, BUFFER_SIZE, N25Q_PAGE_TO_ADDR(1));
-    xprintf("read data: \n");
-    // 打印读出来的数据
-    for (i = 0; i < BUFFER_SIZE; i++)
-        xprintf("0x%x\n", read_data[i]);
-
-
-    flash_n25q_set_dummy_clock_cycles(DUMMY_CNT);
-    // 使能N25Q QSPI模式
-    flash_n25q_enable_quad_mode(1);
-    // 使能SPI控制器QSPI模式
-    spi0_set_spi_mode(SPI_MODE_QUAD);
-    xprintf("read ID through QUAD SPI mode\n");
-    id = flash_n25q_multi_io_read_id();
-    xprintf("manf id = 0x%2x\n", id.manf_id);
-    xprintf("mem type = 0x%2x\n", id.mem_type);
-    xprintf("mem cap = 0x%2x\n", id.mem_cap);
-    flash_n25q_quad_output_fast_read(N25Q_PAGE_TO_ADDR(1), read_data, BUFFER_SIZE);
-    xprintf("fast read data: \n");
-    for (i = 0; i < BUFFER_SIZE; i++)
-        xprintf("0x%x\n", read_data[i]);
-    // 失能N25Q QSPI模式
-    flash_n25q_enable_quad_mode(0);
+    standard_spi_test();
+    quad_spi_test();
 
     while (1);
 }