diff --git a/ports/renesas-ra/boards/ARDUINO_PORTENTA_C33/manifest.py b/ports/renesas-ra/boards/ARDUINO_PORTENTA_C33/manifest.py
index b3c6b02e5b..7b35b54c7a 100644
--- a/ports/renesas-ra/boards/ARDUINO_PORTENTA_C33/manifest.py
+++ b/ports/renesas-ra/boards/ARDUINO_PORTENTA_C33/manifest.py
@@ -10,3 +10,9 @@ require("logging")
 
 # Bluetooth
 require("aioble")
+
+# Register external library
+add_library("arduino-lib", "$(ARDUINO_LIB_DIR)")
+
+# CMWX1 Lora module.
+require("cmwx1", library="arduino-lib")
diff --git a/ports/renesas-ra/boards/ARDUINO_PORTENTA_C33/mpconfigboard.mk b/ports/renesas-ra/boards/ARDUINO_PORTENTA_C33/mpconfigboard.mk
index de9902c16c..9bb336d65e 100644
--- a/ports/renesas-ra/boards/ARDUINO_PORTENTA_C33/mpconfigboard.mk
+++ b/ports/renesas-ra/boards/ARDUINO_PORTENTA_C33/mpconfigboard.mk
@@ -18,5 +18,8 @@ MICROPY_SSL_MBEDTLS = 1
 MICROPY_PY_NETWORK = 1
 MICROPY_PY_NETWORK_ESP_HOSTED = 1
 
+ARDUINO_LIB_DIR = lib/arduino-lib
+GIT_SUBMODULES += $(ARDUINO_LIB_DIR)
 FROZEN_MANIFEST = $(BOARD_DIR)/manifest.py
+MICROPY_MANIFEST_ARDUINO_LIB_DIR = $(TOP)/$(ARDUINO_LIB_DIR)
 MBEDTLS_CONFIG_FILE = '"$(BOARD_DIR)/mbedtls_config_board.h"'