diff --git a/ch32v003fun/ch32v003fun.c b/ch32v003fun/ch32v003fun.c
index 327c5af7..f2776fc2 100644
--- a/ch32v003fun/ch32v003fun.c
+++ b/ch32v003fun/ch32v003fun.c
@@ -762,7 +762,7 @@ extern uint32_t * _edata;
 void DefaultIRQHandler( void )
 {
 	// Infinite Loop
-#if defined( DEBUG )
+#if FUNCONF_DEBUG
 	printf( "DefaultIRQHandler MSTATUS:%08x MTVAL:%08x MCAUSE:%08x MEPC:%08x\n", (int)__get_MSTATUS(), (int)__get_MTVAL(), (int)__get_MCAUSE(), (int)__get_MEPC() );
 #endif
 	asm volatile( "1: j 1b" );
diff --git a/ch32v003fun/ch32v003fun.h b/ch32v003fun/ch32v003fun.h
index 4fa76063..7ded648e 100644
--- a/ch32v003fun/ch32v003fun.h
+++ b/ch32v003fun/ch32v003fun.h
@@ -68,6 +68,7 @@
 #define FUNCONF_DEBUGPRINTF_TIMEOUT 160000 // Arbitrary time units
 #define FUNCONF_ENABLE_HPE 1            // Enable hardware interrupt stack.  Very good on QingKeV4, i.e. x035, v10x, v20x, v30x, but questionable on 003.
 #define FUNCONF_USE_5V_VDD 0            // Enable this if you plan to use your part at 5V - affects USB and PD configration on the x035.
+#define FUNCONF_DEBUG      0            // Log fatal errors with "printf"
 */
 
 // Sanity check for when porting old code.
@@ -110,6 +111,10 @@
 	#endif
 #endif
 
+#if !defined( FUNCONF_DEBUG )
+	#define FUNCONF_DEBUG 0
+#endif
+
 #if defined( CH32X03x ) && FUNCONF_USE_PLL
 	#error No PLL on the X03x
 #endif
@@ -13432,8 +13437,6 @@ static inline void __set_MCAUSE(uint32_t value)
 	__ASM volatile("csrw mcause, %0":: "r"(value));
 }
 
-#if defined(CH32V10x) || defined(CH32V20x) || defined(CH32V30x)
-
 /*********************************************************************
  * @fn      __get_MTVAL
  * @brief   Return the Machine Trap Value Register
@@ -13457,8 +13460,6 @@ static inline void __set_MTVAL(uint32_t value)
 	__ASM volatile ("csrw mtval, %0" : : "r" (value) );
 }
 
-#endif
-
 /*********************************************************************
  * @fn      __get_MVENDORID
  * @brief   Return Vendor ID Register
diff --git a/ch32v003fun/ch32v003fun.mk b/ch32v003fun/ch32v003fun.mk
index 1ebc330a..de92615c 100644
--- a/ch32v003fun/ch32v003fun.mk
+++ b/ch32v003fun/ch32v003fun.mk
@@ -29,6 +29,10 @@ MINICHLINK?=$(CH32V003FUN)/../minichlink
 WRITE_SECTION?=flash
 SYSTEM_C?=$(CH32V003FUN)/ch32v003fun.c
 
+ifeq ($(DEBUG),1)
+	EXTRA_CFLAGS+=-DFUNCONF_DEBUG=1
+endif
+
 CFLAGS?=-g -Os -flto -ffunction-sections -fdata-sections -fmessage-length=0 -msmall-data-limit=8
 LDFLAGS+=-Wl,--print-memory-usage