diff --git a/ports/atmel-samd/boards/hallowing_m0_express/mpconfigboard.mk b/ports/atmel-samd/boards/hallowing_m0_express/mpconfigboard.mk
index 0669939260..222a217b30 100644
--- a/ports/atmel-samd/boards/hallowing_m0_express/mpconfigboard.mk
+++ b/ports/atmel-samd/boards/hallowing_m0_express/mpconfigboard.mk
@@ -18,4 +18,4 @@ FROZEN_MPY_DIRS += $(TOP)/frozen/Adafruit_CircuitPython_LIS3DH
 FROZEN_MPY_DIRS += $(TOP)/frozen/Adafruit_CircuitPython_NeoPixel
 
 # To keep the build small
-CFLAGS_INLINE_LIMIT = 50
+CIRCUITPY_I2CSLAVE = 0