diff --git a/Makefile b/Makefile
index 4e2896a6..71f77103 100644
--- a/Makefile
+++ b/Makefile
@@ -458,6 +458,9 @@ retest:
 TWISTER_RESULTS=../twister-out.unit_testing
 .PHONY: twister
 twister:
+ifndef ZEPHYR_BASE
+	$(error ZEPHYR_BASE is undefined)
+endif
 	$(ZEPHYR_BASE)/scripts/twister -O $(TWISTER_RESULTS) -p unit_testing -T zephyr/tests
 
 .PHONY: twister-clean
diff --git a/src/bacnet/basic/object/lo.c b/src/bacnet/basic/object/lo.c
index 9a951334..85509002 100644
--- a/src/bacnet/basic/object/lo.c
+++ b/src/bacnet/basic/object/lo.c
@@ -997,7 +997,7 @@ static bool Lighting_Output_Lighting_Command_Write(
                 debug_printf("LO[%u]: Lighting-Command@%u Fade-To "
                     "Target=%f Fade=%u\n",
                     object_instance, priority,
-                    value->target_level, value->fade_time);
+                    (double)value->target_level, value->fade_time);
                 Lighting_Command_Fade_To(pObject, priority,
                     value->target_level, value->fade_time);
                 status = true;
@@ -1006,7 +1006,7 @@ static bool Lighting_Output_Lighting_Command_Write(
                 debug_printf("LO[%u]: Lighting-Command@%u Ramp-To "
                     "Target=%f Ramp-Rate=%f\n",
                     object_instance, priority,
-                    value->target_level, value->ramp_rate);
+                    (double)value->target_level, (double)value->ramp_rate);
                 Lighting_Command_Ramp_To(pObject, priority,
                     value->target_level, value->ramp_rate);
                 status = true;
@@ -1018,7 +1018,7 @@ static bool Lighting_Output_Lighting_Command_Write(
                 debug_printf("LO[%u]: Lighting-Command@%u Step "
                     "Step-Increment=%f\n",
                     object_instance, priority,
-                    value->step_increment);
+                    (double)value->step_increment);
                 Lighting_Command_Step(pObject,priority,
                     value->operation,value->step_increment);
                 status = true;
@@ -2307,7 +2307,7 @@ Lighting_Output_Fade_Handler(uint32_t object_instance, uint16_t milliseconds)
             object_instance,
             bactext_lighting_operation_name(
             pObject->Lighting_Command.operation),
-            pObject->Tracking_Value);
+            (double)pObject->Tracking_Value);
     }
 }
 
@@ -2371,7 +2371,7 @@ Lighting_Output_Ramp_Handler(uint32_t object_instance, uint16_t milliseconds)
             }
         } else if (isgreater(old_value, target_value)) {
             debug_printf("LO[%u] Ramp Handler Down steps=%f tracking=%f\n",
-                object_instance, steps, old_value);
+                object_instance, (double)steps, (double)old_value);
             if (isgreater(old_value, steps)) {
                 step_value = old_value - steps;
             } else {
@@ -2383,7 +2383,7 @@ Lighting_Output_Ramp_Handler(uint32_t object_instance, uint16_t milliseconds)
             }
         } else {
             debug_printf("LO[%u] Ramp Handler at target=%f tracking=%f\n",
-                object_instance, target_value, old_value);
+                object_instance, (double)target_value, (double)old_value);
             /* stop ramping */
             pObject->Lighting_Command.operation = BACNET_LIGHTS_STOP;
         }
@@ -2410,7 +2410,7 @@ Lighting_Output_Ramp_Handler(uint32_t object_instance, uint16_t milliseconds)
             object_instance,
             bactext_lighting_operation_name(
             pObject->Lighting_Command.operation),
-            pObject->Tracking_Value);
+            (double)pObject->Tracking_Value);
     }
 }
 
@@ -2458,7 +2458,7 @@ static void Lighting_Output_Step_Up_Handler(uint32_t object_instance)
                 object_instance,
                 bactext_lighting_operation_name(
                 pObject->Lighting_Command.operation),
-                pObject->Tracking_Value);
+                (double)pObject->Tracking_Value);
         }
     }
 }
@@ -2509,7 +2509,7 @@ static void Lighting_Output_Step_Down_Handler(uint32_t object_instance)
             object_instance,
             bactext_lighting_operation_name(
             pObject->Lighting_Command.operation),
-            pObject->Tracking_Value);
+            (double)pObject->Tracking_Value);
     }
 }
 
@@ -2555,7 +2555,7 @@ static void Lighting_Output_Step_On_Handler(uint32_t object_instance)
             object_instance,
             bactext_lighting_operation_name(
             pObject->Lighting_Command.operation),
-            pObject->Tracking_Value);
+            (double)pObject->Tracking_Value);
     }
 }
 
@@ -2606,7 +2606,7 @@ static void Lighting_Output_Step_Off_Handler(uint32_t object_instance)
             object_instance,
             bactext_lighting_operation_name(
             pObject->Lighting_Command.operation),
-            pObject->Tracking_Value);
+            (double)pObject->Tracking_Value);
     }
 }
 
diff --git a/test/bacnet/basic/object/lo/CMakeLists.txt b/test/bacnet/basic/object/lo/CMakeLists.txt
index 005109d4..551fee8d 100644
--- a/test/bacnet/basic/object/lo/CMakeLists.txt
+++ b/test/bacnet/basic/object/lo/CMakeLists.txt
@@ -48,6 +48,7 @@ add_executable(${PROJECT_NAME}
 	${SRC_DIR}/bacnet/basic/sys/bigend.c
 	${SRC_DIR}/bacnet/basic/sys/days.c
 	${SRC_DIR}/bacnet/basic/sys/color_rgb.c
+	${SRC_DIR}/bacnet/basic/sys/debug.c
 	${SRC_DIR}/bacnet/basic/sys/keylist.c
 	${SRC_DIR}/bacnet/basic/sys/linear.c
 	${SRC_DIR}/bacnet/datetime.c
diff --git a/zephyr/tests/bacnet/basic/object/lo/CMakeLists.txt b/zephyr/tests/bacnet/basic/object/lo/CMakeLists.txt
index 3b5e4a68..bba50f09 100644
--- a/zephyr/tests/bacnet/basic/object/lo/CMakeLists.txt
+++ b/zephyr/tests/bacnet/basic/object/lo/CMakeLists.txt
@@ -57,6 +57,7 @@ if(BOARD STREQUAL unit_testing)
     ${BACNET_SRC}/special_event.c
     ${BACNET_SRC}/basic/sys/bigend.c
     ${BACNET_SRC}/basic/sys/linear.c
+    ${BACNET_SRC}/basic/sys/debug.c
     ${BACNET_SRC}/basic/sys/keylist.c
     ${BACNET_SRC}/bactimevalue.c
     )