diff --git a/libraries/DataFlash/DataFlash.cpp b/libraries/DataFlash/DataFlash.cpp
index 5e490b5734..f7372d4cb0 100644
--- a/libraries/DataFlash/DataFlash.cpp
+++ b/libraries/DataFlash/DataFlash.cpp
@@ -273,7 +273,7 @@ void DataFlash_Class::start_new_log(void)
 
 // This function finds the first and last pages of a log file
 // The first page may be greater than the last page if the DataFlash has been filled and partially overwritten.
-void DataFlash_Class::get_log_boundaries(uint8_t log_num, int & start_page, int & end_page)
+void DataFlash_Class::get_log_boundaries(uint8_t log_num, int16_t & start_page, int16_t & end_page)
 {
 	int num = get_num_logs();
 	int look;
diff --git a/libraries/DataFlash/DataFlash.h b/libraries/DataFlash/DataFlash.h
index 3138471619..a55caebe5d 100644
--- a/libraries/DataFlash/DataFlash.h
+++ b/libraries/DataFlash/DataFlash.h
@@ -84,7 +84,7 @@ class DataFlash_Class
 
 	// high level interface
 	int find_last_log(void);
-	void get_log_boundaries(uint8_t log_num, int & start_page, int & end_page);
+	void get_log_boundaries(uint8_t log_num, int16_t & start_page, int16_t & end_page);
 	uint8_t get_num_logs(void);
 	void start_new_log(void);