diff --git a/build/.gitignore b/build/.gitignore
index 8c762d0..5c37b4f 100644
--- a/build/.gitignore
+++ b/build/.gitignore
@@ -1,5 +1,5 @@
 *
 
 !.gitignore
-!.system_same54.c
-!.gcc/*
+!system_same54.c
+!gcc/*
diff --git a/build/system_same54.c b/build/system_same54.c
new file mode 100644
index 0000000..468990e
--- /dev/null
+++ b/build/system_same54.c
@@ -0,0 +1,64 @@
+/**
+ * \file
+ *
+ * \brief Low-level initialization functions called upon chip startup.
+ *
+ * Copyright (c) 2019 Microchip Technology Inc.
+ *
+ * \asf_license_start
+ *
+ * \page License
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the Licence at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * \asf_license_stop
+ *
+ */
+
+#include "same54.h"
+
+/**
+ * Initial system clock frequency. The System RC Oscillator (RCSYS) provides
+ *  the source for the main clock at chip startup.
+ */
+#define __SYSTEM_CLOCK (48000000)
+
+uint32_t SystemCoreClock = __SYSTEM_CLOCK; /*!< System Clock Frequency (Core Clock)*/
+
+/**
+ * Initialize the system
+ *
+ * @brief  Setup the microcontroller system.
+ *         Initialize the System and update the SystemCoreClock variable.
+ */
+void SystemInit(void)
+{
+	// Keep the default device state after reset
+	SystemCoreClock = __SYSTEM_CLOCK;
+	return;
+}
+
+/**
+ * Update SystemCoreClock variable
+ *
+ * @brief  Updates the SystemCoreClock with current core Clock
+ *         retrieved from cpu registers.
+ */
+void SystemCoreClockUpdate(void)
+{
+	// Not implemented
+	SystemCoreClock = __SYSTEM_CLOCK;
+	return;
+}