diff --git a/srv/debug.c b/srv/debug.c
index 00f1265..23d3794 100644
--- a/srv/debug.c
+++ b/srv/debug.c
@@ -11,6 +11,8 @@
 #include "dma_mbuf.h"
 #include "format.h"
 
+#if DEBUG_TRACE || DEBUG_WARN || DEBUG_ERROR
+
 
 //--local definitions-----------------------------------------------------------
 
@@ -27,8 +29,6 @@ static uint8_t tx_buffer[BUFFER_SIZE];
 
 //--public functions------------------------------------------------------------
 
-#if DEBUG_TRACE || DEBUG_WARN || DEBUG_ERROR
-
 void _debug_init(enum UsartPeriph usart, enum GpioPort tx_port,
 		enum GpioPin tx_pin)
 {
@@ -45,16 +45,12 @@ void _debug_init(enum UsartPeriph usart, enum GpioPort tx_port,
 	debug_trace("------------------------------------------------------------------------------\n");
 }
 
-#endif
-
-#if DEBUG_TRACE
-
-void _debug_trace(char* format, ...)
+void _debug_print(const char* restrict header,
+		const char* restrict format, ...)
 {
-	write_debug('T', nullptr);
-	write_debug(':', nullptr);
 	va_list va;
 	va_start(va, format);
+	format_vfctprintf(write_debug, nullptr, header, va);
 	format_vfctprintf(write_debug, nullptr, format, va);
 	va_end(va);
 	write_debug('\n', nullptr);
@@ -63,40 +59,13 @@ void _debug_trace(char* format, ...)
 	while (dma_mbuf_switch(&mbuf)) {}
 }
 
-#endif
-
-#if DEBUG_WARN
-
-void _debug_warn(char* format, ...)
-{
-	print_debug("W:");
-	print_debug(format);
-
-	//ensure everything is written when done
-	while (dma_mbuf_switch(&mbuf)) {}
-}
-
-#endif
-
-#if DEBUG_ERROR
-
-void _debug_error(char* format, ...)
-{
-	print_debug("E:");
-	print_debug(format);
-
-	//ensure everything is written when done
-	while (dma_mbuf_switch(&mbuf)) {}
-}
-
-#endif
 
 //--local functions-------------------------------------------------------------
 
-#if DEBUG_TRACE || DEBUG_WARN || DEBUG_ERROR
-
 static uint32_t write_debug(uint8_t c, void* arg)
 {
+	(void)arg; //unused, required because of FormatCallback
+
 	while (dma_mbuf_write_byte(&mbuf, c))
 	{
 		//buffer is full, wait until transfer started
@@ -106,5 +75,6 @@ static uint32_t write_debug(uint8_t c, void* arg)
 	return 0;
 }
 
-#endif
+#endif //DEBUG_TRACE || DEBUG_WARN || DEBUG_ERROR
+
 
diff --git a/srv/debug.h b/srv/debug.h
index b954511..7fcb31d 100644
--- a/srv/debug.h
+++ b/srv/debug.h
@@ -14,8 +14,8 @@
 #include "../drv/gpio.h"
 
 #define DEBUG_TRACE 1
-#define DEBUG_WARN 0
-#define DEBUG_ERROR 0
+#define DEBUG_WARN 1
+#define DEBUG_ERROR 1
 
 
 //--type definitions------------------------------------------------------------
@@ -27,19 +27,22 @@
 #endif
 
 #if DEBUG_TRACE
-#define debug_trace(format, ...) _debug_trace(format __VA_OPT__(,) __VA_ARGS__)
+#define debug_trace(format, ...) _debug_print("T:", \
+		format __VA_OPT__(,) __VA_ARGS__)
 #else
 #define debug_trace(format, ...) do {} while (0)
 #endif
 
 #if DEBUG_WARN
-#define debug_warn(format, ...) _debug_warn(format __VA_OPT__(,) __VA_ARGS__)
+#define debug_warn(format, ...) _debug_print("W:", \
+		format __VA_OPT__(,) __VA_ARGS__)
 #else
 #define debug_warn(format, ...) do {} while (0)
 #endif
 
 #if DEBUG_ERROR
-#define debug_error(format, ...) _debug_error(format __VA_OPT__(,) __VA_ARGS__)
+#define debug_error(format, ...) _debug_print("E:", \
+		format __VA_OPT__(,) __VA_ARGS__)
 #else
 #define debug_error(format, ...) do {} while (0)
 #endif
@@ -47,12 +50,15 @@
 
 //--functions-------------------------------------------------------------------
 
+#if DEBUG_TRACE || DEBUG_WARN || DEBUG_ERROR
+
 void _debug_init(enum UsartPeriph usart, enum GpioPort tx_port,
 		enum GpioPin tx_pin);
-void _debug_trace(char* format, ...);
-void _debug_warn(char* format, ...);
-void _debug_error(char* format, ...);
 
+void _debug_print(const char* restrict header,
+		const char* restrict format, ...);
+
+#endif
 
 #endif //_DEBUG_H_