diff --git a/makefiles/tools/pyocd.inc.mk b/makefiles/tools/pyocd.inc.mk
index 4b1593f841..aa386540ea 100644
--- a/makefiles/tools/pyocd.inc.mk
+++ b/makefiles/tools/pyocd.inc.mk
@@ -8,3 +8,8 @@ FFLAGS ?= flash $(FLASHFILE)
 DEBUGGER_FLAGS ?= debug $(ELFFILE)
 DEBUGSERVER_FLAGS ?= debug-server
 RESET_FLAGS ?= reset
+
+# Add serial matching command, only if DEBUG_ADAPTER_ID was specified
+ifneq (,$(DEBUG_ADAPTER_ID))
+  export PYOCD_ADAPTER_INIT += -u $(DEBUG_ADAPTER_ID)
+endif