diff --git a/ports/stm/Makefile b/ports/stm/Makefile
index 08cb36ddf2..a982de765b 100755
--- a/ports/stm/Makefile
+++ b/ports/stm/Makefile
@@ -81,12 +81,12 @@ INC += -I../../supervisor/shared/usb
 
 #Debugging/Optimization
 ifeq ($(DEBUG), 1)
-	CFLAGS += -ggdb
+	CFLAGS += -ggdb3
 	# You may want to enable these flags to make setting breakpoints easier.
 	CFLAGS += -fno-inline -fno-ipa-sra
 else
 	CFLAGS += -Os -DNDEBUG
-	CFLAGS += -ggdb
+	CFLAGS += -ggdb3
 	# TODO: Test with -flto
 	# CFLAGS += -flto
 endif
diff --git a/ports/stm/st_driver b/ports/stm/st_driver
index 3fc2e0f3db..1900834751 160000
--- a/ports/stm/st_driver
+++ b/ports/stm/st_driver
@@ -1 +1 @@
-Subproject commit 3fc2e0f3db155b33177bb0705e0dd65cadb58412
+Subproject commit 1900834751fd6754457874b8c971690bab33e0a7