added ptc.h to instance folder

CMSIS-Atmel/CMSIS/Device/ATMEL/samd21/include/instance/ptc.h

@@ -0,0 +1,36 @@
+/**
+ * \file
+ *
+ * \brief Instance description for PTC
+ *
+ * Copyright (c) 2018 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
+ *
+ */
+
+#ifndef _SAMD21_PTC_INSTANCE_
+#define _SAMD21_PTC_INSTANCE_
+
+/* ========== Instance parameters for PTC peripheral ========== */
+#define PTC_GCLK_ID                 34       // Index of Generic Clock
+
+#endif /* _SAMD21_PTC_INSTANCE_ */