From 0186fabb3bafd823f1ca9d48f44f0de15e90f4e8 Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <tridge@samba.org>
Date: Mon, 24 Dec 2012 07:30:50 +1100
Subject: [PATCH] build: allow building with the "Empty" HAL

useful for porting
---
 libraries/AP_HAL/AP_HAL_Boards.h | 2 ++
 mk/Arduino.mk                    | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/libraries/AP_HAL/AP_HAL_Boards.h b/libraries/AP_HAL/AP_HAL_Boards.h
index 4b4e8fd635..3b987afbb1 100644
--- a/libraries/AP_HAL/AP_HAL_Boards.h
+++ b/libraries/AP_HAL/AP_HAL_Boards.h
@@ -27,6 +27,8 @@
 #define AP_HAL_BOARD_DRIVER AP_HAL_AVR_APM2
 #elif CONFIG_HAL_BOARD == HAL_BOARD_AVR_SITL
 #define AP_HAL_BOARD_DRIVER AP_HAL_AVR_SITL
+#elif CONFIG_HAL_BOARD == HAL_BOARD_EMPTY
+#define AP_HAL_BOARD_DRIVER AP_HAL_Empty
 #else
 #error "Unknown CONFIG_HAL_BOARD type"
 #endif
diff --git a/mk/Arduino.mk b/mk/Arduino.mk
index 00ef242c4d..b2ba451846 100644
--- a/mk/Arduino.mk
+++ b/mk/Arduino.mk
@@ -499,6 +499,10 @@ apm2: HAL_BOARD = HAL_BOARD_APM2
 apm2: TOOLCHAIN = AVR
 apm2: all
 
+empty: HAL_BOARD = HAL_BOARD_EMPTY
+empty: TOOLCHAIN = AVR
+empty: all
+
 .PHONY: upload
 upload: $(SKETCHHEX)
 	$(AVRDUDE) -c $(UPLOAD_PROTOCOL) -p $(MCU) -P $(PORT) -b$(UPLOAD_SPEED) $(USERAVRDUDEFLAGS) -U flash:w:$(SKETCHHEX):i