1 files changed, 1 insertions, 1 deletions
diff --git a/Arduino.mk b/Arduino.mk
index 60bec1c..f9819eb 100644
--- a/Arduino.mk
+++ b/Arduino.mk
@@ -1340,7 +1340,7 @@ size:	$(TARGET_HEX)
 		$(call avr_size,$(TARGET_ELF),$(TARGET_HEX))
 
 show_boards:
-		@$(CAT) "$(BOARDS_TXT)" | grep -E "^[[:alnum:]]+.name" | sort -uf | sed 's/.name=/:/' | column -s: -t
+		@$(CAT) "$(BOARDS_TXT)" | grep -E "^[a-zA-Z0-9_]+.name" | sort -uf | sed 's/.name=/:/' | column -s: -t
 
 monitor:
 		$(MONITOR_CMD) $(call get_monitor_port) $(MONITOR_BAUDRATE)