diff --git a/core/esp_spi.c b/core/esp_spi.c
index 7a4c359..720da18 100644
--- a/core/esp_spi.c
+++ b/core/esp_spi.c
@@ -248,33 +248,33 @@ size_t spi_transfer(uint8_t bus, const void *out_data, void *in_data, size_t len
 
 static void _repeat_send(uint8_t bus, uint32_t* dword,int32_t* repeats,spi_word_size_t size)
 {
-	uint8_t i = 0 ;
-	while(*repeats > 0)
-	{
-		uint16_t bytes_to_transfer = __min(*repeats * size , _SPI_BUF_SIZE);
-		_wait(bus);
-		_set_size(bus,bytes_to_transfer);
-		for(i = 0; i < (bytes_to_transfer + 3) / 4;i++)
-			SPI(bus).W[i] = *dword; //need test with memcpy !
-		_start(bus);
-		*repeats -= (bytes_to_transfer / size ) ;
-	}
-	_wait(bus);
+    uint8_t i = 0 ;
+    while(*repeats > 0)
+    {
+        uint16_t bytes_to_transfer = __min(*repeats * size , _SPI_BUF_SIZE);
+        _wait(bus);
+        _set_size(bus,bytes_to_transfer);
+        for(i = 0; i < (bytes_to_transfer + 3) / 4;i++)
+            SPI(bus).W[i] = *dword; //need test with memcpy !
+        _start(bus);
+        *repeats -= (bytes_to_transfer / size ) ;
+    }
+    _wait(bus);
 }
 
 void spi_repeat_send_8(uint8_t bus, uint8_t data,int32_t repeats)
 {
-	uint32_t dword = data << 24 | data << 16 | data << 8 | data;
-	_repeat_send(bus,&dword,&repeats, SPI_8BIT);
+    uint32_t dword = data << 24 | data << 16 | data << 8 | data;
+    _repeat_send(bus,&dword,&repeats, SPI_8BIT);
 }
 
 void spi_repeat_send_16(uint8_t bus, uint16_t data,int32_t repeats)
 {
-	uint32_t dword = data << 16 | data;
-	_repeat_send(bus,&dword,&repeats, SPI_16BIT);
+    uint32_t dword = data << 16 | data;
+    _repeat_send(bus,&dword,&repeats, SPI_16BIT);
 }
 
 void spi_repeat_send_32(uint8_t bus, uint32_t data,int32_t repeats)
 {
-	_repeat_send(bus,&data,&repeats, SPI_32BIT);
+    _repeat_send(bus,&data,&repeats, SPI_32BIT);
 }
diff --git a/core/include/esp/spi.h b/core/include/esp/spi.h
index d825cb1..4b31144 100644
--- a/core/include/esp/spi.h
+++ b/core/include/esp/spi.h
@@ -186,7 +186,7 @@ void spi_set_frequency_div(uint8_t bus, uint32_t divider);
 inline uint32_t spi_get_frequency_div(uint8_t bus)
 {
     return (FIELD2VAL(SPI_CLOCK_DIV_PRE, SPI(bus).CLOCK) + 1) |
-           (FIELD2VAL(SPI_CLOCK_COUNT_NUM, SPI(bus).CLOCK) + 1);
+            (FIELD2VAL(SPI_CLOCK_COUNT_NUM, SPI(bus).CLOCK) + 1);
 }
 /**
  * \brief Get SPI bus frequency in Hz
@@ -196,8 +196,8 @@ inline uint32_t spi_get_frequency_div(uint8_t bus)
 inline uint32_t spi_get_frequency_hz(uint8_t bus)
 {
     return APB_CLK_FREQ /
-        (FIELD2VAL(SPI_CLOCK_DIV_PRE, SPI(bus).CLOCK) + 1) /
-        (FIELD2VAL(SPI_CLOCK_COUNT_NUM, SPI(bus).CLOCK) + 1);
+            (FIELD2VAL(SPI_CLOCK_DIV_PRE, SPI(bus).CLOCK) + 1) /
+            (FIELD2VAL(SPI_CLOCK_COUNT_NUM, SPI(bus).CLOCK) + 1);
 }
 
 /**
@@ -230,8 +230,8 @@ void spi_set_endianness(uint8_t bus, spi_endianness_t endianness);
 inline spi_endianness_t spi_get_endianness(uint8_t bus)
 {
     return SPI(bus).USER0 & (SPI_USER0_WR_BYTE_ORDER | SPI_USER0_RD_BYTE_ORDER)
-        ? SPI_BIG_ENDIAN
-        : SPI_LITTLE_ENDIAN;
+            ? SPI_BIG_ENDIAN
+                    : SPI_LITTLE_ENDIAN;
 }
 
 /**
@@ -291,12 +291,12 @@ size_t spi_transfer(uint8_t bus, const void *out_data, void *in_data, size_t len
  */
 static inline void spi_set_command(uint8_t bus,uint8_t bits, uint16_t data)
 {
-	if(!bits) return ;
-	SPI(bus).USER0 |= SPI_USER0_COMMAND ; //enable COMMAND function in SPI module
-	uint16_t command = data << (16-bits); //align command data to high bits
-	command = ((command>>8)&0xff) | ((command<<8)&0xff00); //swap byte order
-	SPI(bus).USER2 =  SET_FIELD(SPI(bus).USER2, SPI_USER2_COMMAND_BITLEN, --bits);
-	SPI(bus).USER2 =  SET_FIELD(SPI(bus).USER2, SPI_USER2_COMMAND_VALUE, command);
+    if(!bits) return ;
+    SPI(bus).USER0 |= SPI_USER0_COMMAND ; //enable COMMAND function in SPI module
+    uint16_t command = data << (16-bits); //align command data to high bits
+    command = ((command>>8)&0xff) | ((command<<8)&0xff00); //swap byte order
+    SPI(bus).USER2 =  SET_FIELD(SPI(bus).USER2, SPI_USER2_COMMAND_BITLEN, --bits);
+    SPI(bus).USER2 =  SET_FIELD(SPI(bus).USER2, SPI_USER2_COMMAND_VALUE, command);
 }
 
 /**
@@ -316,10 +316,10 @@ static inline void spi_set_command(uint8_t bus,uint8_t bits, uint16_t data)
  */
 static inline void spi_set_address(uint8_t bus,uint8_t bits, uint32_t data)
 {
-	if(!bits) return ;
-	SPI(bus).USER1 = SET_FIELD(SPI(bus).USER1, SPI_USER1_ADDR_BITLEN, --bits);
-	SPI(bus).USER0 |= SPI_USER0_ADDR ; //enable ADDRess function in SPI module
-	SPI(bus).ADDR = data<<(32-bits) ; //align address data to high bits
+    if(!bits) return ;
+    SPI(bus).USER1 = SET_FIELD(SPI(bus).USER1, SPI_USER1_ADDR_BITLEN, --bits);
+    SPI(bus).USER0 |= SPI_USER0_ADDR ; //enable ADDRess function in SPI module
+    SPI(bus).ADDR = data<<(32-bits) ; //align address data to high bits
 }
 
 /**
@@ -335,14 +335,14 @@ static inline void spi_set_address(uint8_t bus,uint8_t bits, uint32_t data)
  *
  * \param bus Bus ID: 0 - system, 1 - user
  * \param bits Number of bits
- * \param pos Address to send for each transfert.
+ * \param pos Position of dummy bit, between Dout and Din if true.
  */
 static inline void spi_set_dummy_bits(uint8_t bus, uint8_t bits, bool pos)
 {
-	if(!bits) return ;
-	if(pos) { SPI(bus).USER0 |= SPI_USER0_MISO; } // Dummy bit will be between Dout and Din data if set
-	SPI(bus).USER0 |= SPI_USER0_DUMMY; //enable dummy bits
-	SPI(bus).USER1 = SET_FIELD(SPI(bus).USER1, SPI_USER1_DUMMY_CYCLELEN, --bits);
+    if(!bits) return ;
+    if(pos) { SPI(bus).USER0 |= SPI_USER0_MISO; } // Dummy bit will be between Dout and Din data if set
+    SPI(bus).USER0 |= SPI_USER0_DUMMY; //enable dummy bits
+    SPI(bus).USER1 = SET_FIELD(SPI(bus).USER1, SPI_USER1_DUMMY_CYCLELEN, --bits);
 }
 
 /**
@@ -351,7 +351,7 @@ static inline void spi_set_dummy_bits(uint8_t bus, uint8_t bits, bool pos)
  */
 static inline void spi_clear_address(uint8_t bus)
 {
-	SPI(bus).USER0 &= ~(SPI_USER0_ADDR) ;
+    SPI(bus).USER0 &= ~(SPI_USER0_ADDR) ;
 }
 
 /**
@@ -361,7 +361,7 @@ static inline void spi_clear_address(uint8_t bus)
 
 static inline void spi_clear_command(uint8_t bus)
 {
-	SPI(bus).USER0 &= ~(SPI_USER0_COMMAND) ;
+    SPI(bus).USER0 &= ~(SPI_USER0_COMMAND) ;
 }
 
 /**
@@ -370,7 +370,7 @@ static inline void spi_clear_command(uint8_t bus)
  */
 static inline void spi_clear_dummy(uint8_t bus)
 {
-	SPI(bus).USER0 &= ~(SPI_USER0_DUMMY | SPI_USER0_MISO ) ;
+    SPI(bus).USER0 &= ~(SPI_USER0_DUMMY | SPI_USER0_MISO);
 }
 
 /**
diff --git a/examples/spi_test/spi_test.c b/examples/spi_test/spi_test.c
index a746ba2..0baccc3 100644
--- a/examples/spi_test/spi_test.c
+++ b/examples/spi_test/spi_test.c
@@ -22,43 +22,43 @@
 
 void loop(void *pvParameters)
 {
-	uint32_t time = 0 ; // SPI transmission time
-	float avr_time = 0 ; // Average of SPI transmission
-	float u = 0 ;
+    uint32_t time = 0 ; // SPI transmission time
+    float avr_time = 0 ; // Average of SPI transmission
+    float u = 0 ;
 
-	spi_init(1, SPI_MODE0, SPI_FREQ_DIV_1M, 1, SPI_LITTLE_ENDIAN, false); // init SPI module
+    spi_init(1, SPI_MODE0, SPI_FREQ_DIV_1M, 1, SPI_LITTLE_ENDIAN, false); // init SPI module
 
 
-	while(1) {
+    while(1) {
 
-		time = sdk_system_get_time();
+        time = sdk_system_get_time();
 
-		spi_set_command(1,1,1) ; // Set one command bit to 1
-		spi_set_address(1,4,8) ; // Set 4 address bits to 8
-		spi_set_dummy_bits(1,4,false); // Set 4 dummy bit before Dout
+        spi_set_command(1,1,1) ; // Set one command bit to 1
+        spi_set_address(1,4,8) ; // Set 4 address bits to 8
+        spi_set_dummy_bits(1,4,false); // Set 4 dummy bit before Dout
 
-		spi_repeat_send_16(1,0xC584,10);  // Send 1 bit command + 4 bits address + 4 bits dummy + 160 bits data
+        spi_repeat_send_16(1,0xC584,10);  // Send 1 bit command + 4 bits address + 4 bits dummy + 160 bits data
 
-		spi_clear_address(1); // remove address
-		spi_clear_command(1); // remove command
-		spi_clear_dummy(1); // remove dummy
+        spi_clear_address(1); // remove address
+        spi_clear_command(1); // remove command
+        spi_clear_dummy(1); // remove dummy
 
 
-		time = sdk_system_get_time() -time ;
-		avr_time = ((avr_time * (float)u ) + (float)time)/((float)u+1.0)  ; // compute average
-		u++;
-		if (u==100) {
-			u=0 ;
-			printf("Time: %f\n",avr_time);
-		}
-		vTaskDelay(100/portTICK_PERIOD_MS);
-	}
+        time = sdk_system_get_time() -time ;
+        avr_time = ((avr_time * (float)u ) + (float)time)/((float)u+1.0)  ; // compute average
+        u++;
+        if (u==100) {
+            u=0 ;
+            printf("Time: %f\n",avr_time);
+        }
+        vTaskDelay(100/portTICK_PERIOD_MS);
+    }
 }
 
 
 void user_init(void)
 {
-	uart_set_baud(0, 115200);
-	printf("SDK version:%s\n", sdk_system_get_sdk_version());
-	xTaskCreate(loop, "loop", 1024, NULL, 2, NULL);
+    uart_set_baud(0, 115200);
+    printf("SDK version:%s\n", sdk_system_get_sdk_version());
+    xTaskCreate(loop, "loop", 1024, NULL, 2, NULL);
 }