diff --git a/Tools/ardupilotwaf/chibios.py b/Tools/ardupilotwaf/chibios.py
index faf094c4fd..819b3474c5 100644
--- a/Tools/ardupilotwaf/chibios.py
+++ b/Tools/ardupilotwaf/chibios.py
@@ -578,6 +578,8 @@ def configure(cfg):
     load_env_vars(cfg.env)
     if env.HAL_NUM_CAN_IFACES and not env.AP_PERIPH:
         setup_canmgr_build(cfg)
+    if env.HAL_NUM_CAN_IFACES and env.AP_PERIPH and int(env.HAL_NUM_CAN_IFACES)>1 and not env.BOOTLOADER:
+        env.DEFINES += [ 'CANARD_MULTI_IFACE=1' ]
     setup_optimization(cfg.env)
 
 def generate_hwdef_h(env):