diff --git a/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py b/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py
index 6d5bc8e595..31c3bd40bd 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py
+++ b/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py
@@ -725,7 +725,7 @@ def get_ram_map():
         ram_map = get_mcu_config('RAM_MAP_EXTERNAL_FLASH', False)
         if ram_map is not None:
             return ram_map
-    elif int(env_vars.get('USE_ALT_RAM_MAP',0)) == '1':
+    elif int(env_vars.get('USE_ALT_RAM_MAP',0)) == 1:
         print("Using ALT_RAM_MAP")
         return get_mcu_config('ALT_RAM_MAP', True)
     return get_mcu_config('RAM_MAP', True)