diff --git a/left/src/debug_over_spi.c b/left/src/debug_over_spi.c
index 28752ed..bd5524b 100644
--- a/left/src/debug_over_spi.c
+++ b/left/src/debug_over_spi.c
@@ -1,8 +1,9 @@
+#ifdef DEBUG_OVER_SPI
+
 #include "debug_over_spi.h"
 #include "config.h"
 #include "fsl_gpio.h"
 
-#ifdef DEBUG_OVER_SPI
 
 #define EXAMPLE_SPI_MASTER (SPI0)
 #define EXAMPLE_SPI_MASTER_SOURCE_CLOCK (kCLOCK_BusClk)
@@ -16,19 +17,13 @@ spi_master_handle_t handle;
 
 static volatile bool masterFinished = true;
 
-#endif
-
 static void masterCallback(SPI_Type *base, spi_master_handle_t *masterHandle, status_t status, void *userData)
 {
-#ifdef DEBUG_OVER_SPI
     masterFinished = true;
-#endif
 }
 
 void DebugOverSpi_Init(void)
 {
-#ifdef DEBUG_OVER_SPI
-
     CLOCK_EnableClock(DEBUG_OVER_SPI_MOSI_CLOCK);
     CLOCK_EnableClock(DEBUG_OVER_SPI_SCK_CLOCK);
 
@@ -45,12 +40,10 @@ void DebugOverSpi_Init(void)
     uint32_t srcFreq = CLOCK_GetFreq(EXAMPLE_SPI_MASTER_SOURCE_CLOCK);
     SPI_MasterInit(EXAMPLE_SPI_MASTER, &userConfig, srcFreq);
     SPI_MasterTransferCreateHandle(EXAMPLE_SPI_MASTER, &handle, masterCallback, NULL);
-#endif
 }
 
 void DebugOverSpi_Send(uint8_t *tx, uint8_t len)
 {
-#ifdef DEBUG_OVER_SPI
     if (masterFinished) {
         masterFinished = false;
         memcpy(srcBuff, tx, MIN(BUFFER_SIZE, len));
@@ -58,5 +51,6 @@ void DebugOverSpi_Send(uint8_t *tx, uint8_t len)
         xfer.dataSize = len;
         SPI_MasterTransferNonBlocking(EXAMPLE_SPI_MASTER, &handle, &xfer);
     }
-#endif
 }
+
+#endif
diff --git a/left/src/debug_over_spi.h b/left/src/debug_over_spi.h
index a97d8ae..4fcd263 100644
--- a/left/src/debug_over_spi.h
+++ b/left/src/debug_over_spi.h
@@ -1,3 +1,5 @@
+#ifdef DEBUG_OVER_SPI
+
 #ifndef __DEBUG_OVER_SPI_H__
 #define __DEBUG_OVER_SPI_H__
 
@@ -25,3 +27,8 @@
     void DebugOverSpi_Send(uint8_t *tx, uint8_t len);
 
 #endif
+
+#else
+    #define DebugOverSpi_Init()
+    #define DebugOverSpi_Send(tx, len)
+#endif