diff --git a/arch/cpu/arm/Makefile.arm b/arch/cpu/arm/Makefile.arm
index 285031e82..83f9b8a36 100644
--- a/arch/cpu/arm/Makefile.arm
+++ b/arch/cpu/arm/Makefile.arm
@@ -29,10 +29,17 @@ else
   CFLAGS += -O2
 endif
 
-### Use CMSIS and the existing dbg-io from arch/cpu/arm/common
-CONTIKI_ARM_DIRS += . common/dbg-io
+### Use CMSIS from arch/cpu/arm/common
+CONTIKI_ARM_DIRS += . 
 CONTIKI_CPU_DIRS += $(addprefix ../arm/, $(CONTIKI_ARM_DIRS))
 
+### Default to use os/lib/dbg-io unless configured to do otherwise
+MAKE_WITH_LIB_DBG_IO ?= 1
+
+ifeq ($(MAKE_WITH_LIB_DBG_IO),1)
+  MODULES += os/lib/dbg-io
+endif
+
 ### CPU-dependent cleanup files
 CLEAN += *.elf *.bin *.lst *.hex *.i16hex
 
diff --git a/arch/cpu/cc2538/Makefile.cc2538 b/arch/cpu/cc2538/Makefile.cc2538
index 891215093..51a5c40c7 100644
--- a/arch/cpu/cc2538/Makefile.cc2538
+++ b/arch/cpu/cc2538/Makefile.cc2538
@@ -28,8 +28,6 @@ CONTIKI_CPU_SOURCEFILES += slip-arch.c slip.c
 CONTIKI_CPU_SOURCEFILES += i2c.c cc2538-temp-sensor.c vdd3-sensor.c
 CONTIKI_CPU_SOURCEFILES += cfs-coffee.c cfs-coffee-arch.c pwm.c
 
-MODULES += os/lib/dbg-io
-
 USB_SOURCEFILES += usb-core.c cdc-acm.c usb-arch.c usb-serial.c cdc-acm-descriptors.c
 
 CPU_START_SOURCEFILES = startup-gcc.c
diff --git a/arch/cpu/cc26xx-cc13xx/Makefile.cc26xx-cc13xx b/arch/cpu/cc26xx-cc13xx/Makefile.cc26xx-cc13xx
index f54a8d72d..00f9ae232 100644
--- a/arch/cpu/cc26xx-cc13xx/Makefile.cc26xx-cc13xx
+++ b/arch/cpu/cc26xx-cc13xx/Makefile.cc26xx-cc13xx
@@ -45,8 +45,6 @@ CONTIKI_CPU_SOURCEFILES += ble-cc2650.c ble-hal-cc26xx.c ble-addr.c rf-ble-cmd.c
 CONTIKI_CPU_SOURCEFILES += random.c soc-trng.c int-master.c
 CONTIKI_CPU_SOURCEFILES += spi-arch.c
 
-MODULES += os/lib/dbg-io
-
 CONTIKI_SOURCEFILES += $(CONTIKI_CPU_SOURCEFILES)
 
 CPU_START_SOURCEFILES += fault-handlers.c $(TI_XXWARE_STARTUP_SRCS)
diff --git a/arch/cpu/simplelink-cc13xx-cc26xx/Makefile.cc13xx-cc26xx b/arch/cpu/simplelink-cc13xx-cc26xx/Makefile.cc13xx-cc26xx
index 3eb11182d..dfd14637e 100644
--- a/arch/cpu/simplelink-cc13xx-cc26xx/Makefile.cc13xx-cc26xx
+++ b/arch/cpu/simplelink-cc13xx-cc26xx/Makefile.cc13xx-cc26xx
@@ -91,9 +91,6 @@ SDK_DEVICES := $(CORE_SDK)/source/ti/devices/$(SDK_DEVICES_NAME)
 
 EXTERNALDIRS += $(SDK_SOURCE) $(SDK_NORTOS)
 
-# CPU-dependent debug source files
-MODULES += os/lib/dbg-io
-
 # CPU-dependent directories
 CONTIKI_CPU_DIRS += . dev $(SUBFAMILY)
 CONTIKI_CPU_DIRS += rf rf-settings rf-settings/$(DEVICE_FAMILY_LC)
diff --git a/arch/platform/jn516x/Makefile.jn516x b/arch/platform/jn516x/Makefile.jn516x
index 6cff59c65..9ad9488d5 100644
--- a/arch/platform/jn516x/Makefile.jn516x
+++ b/arch/platform/jn516x/Makefile.jn516x
@@ -103,8 +103,6 @@ endif
 CONTIKI_TARGET_DIRS = . dev
 CONTIKI_TARGET_MAIN = platform.c
 
-MODULES += os/lib/dbg-io
-
 ifeq ($(JN516x_WITH_DR1175),1)
 JN516x_WITH_DR1174 = 1
 CFLAGS += -DSENSOR_BOARD_DR1175
diff --git a/arch/platform/nrf52dk/Makefile.nrf52dk b/arch/platform/nrf52dk/Makefile.nrf52dk
index 7e931880a..e1d56c090 100644
--- a/arch/platform/nrf52dk/Makefile.nrf52dk
+++ b/arch/platform/nrf52dk/Makefile.nrf52dk
@@ -9,12 +9,12 @@ CONTIKI_TARGET_DIRS += . dev config
 CONTIKI_SOURCEFILES += platform.c leds-arch.c nrf52dk-sensors.c button-sensor.c temperature-sensor.c
 
 ifeq ($(NRF52_USE_RTT),1)
-### Use the existing debug I/O in arch/cpu/arm/common
+### Suppress the existing debug I/O in os/lib
+MAKE_WITH_LIB_DBG_IO = 0
 CONTIKI_TARGET_DIRS += rtt
 CONTIKI_SOURCEFILES += rtt-printf.c segger-rtt.c segger-rtt-printf.c
 else
 CONTIKI_SOURCEFILES += dbg.c
-MODULES += os/lib/dbg-io
 endif
 
 ### Unless the example dictates otherwise, build with code size optimisations switched off