NFC: application + rfal + driver.

lib/ST25RFAL002/source/rfal_crc.c

@@ -0,0 +1,86 @@
+
+/******************************************************************************
+  * \attention
+  *
+  * <h2><center>&copy; COPYRIGHT 2020 STMicroelectronics</center></h2>
+  *
+  * Licensed under ST MYLIBERTY SOFTWARE LICENSE AGREEMENT (the "License");
+  * You may not use this file except in compliance with the License.
+  * You may obtain a copy of the License at:
+  *
+  *        www.st.com/myliberty
+  *
+  * 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,
+  * AND SPECIFICALLY DISCLAIMING THE IMPLIED WARRANTIES OF MERCHANTABILITY,
+  * FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
+  * See the License for the specific language governing permissions and
+  * limitations under the License.
+  *
+******************************************************************************/
+
+/*
+ *      PROJECT:   ST25R391x firmware
+ *      Revision:
+ *      LANGUAGE:  ISO C99
+ */
+
+/*! \file rfal_crc.c
+ *
+ *  \author Oliver Regenfelder
+ *
+ *  \brief CRC calculation implementation
+ *
+ */
+
+/*
+******************************************************************************
+* INCLUDES
+******************************************************************************
+*/
+#include "rfal_crc.h"
+
+/*
+******************************************************************************
+* LOCAL FUNCTION PROTOTYPES
+******************************************************************************
+*/
+static uint16_t rfalCrcUpdateCcitt(uint16_t crcSeed, uint8_t dataByte);
+
+/*
+******************************************************************************
+* GLOBAL FUNCTIONS
+******************************************************************************
+*/
+uint16_t rfalCrcCalculateCcitt(uint16_t preloadValue, const uint8_t* buf, uint16_t length)
+{
+    uint16_t crc = preloadValue;
+    uint16_t index;
+
+    for (index = 0; index < length; index++)
+    {
+        crc = rfalCrcUpdateCcitt(crc, buf[index]);
+    }
+
+    return crc;
+}
+
+/*
+******************************************************************************
+* LOCAL FUNCTIONS
+******************************************************************************
+*/
+static uint16_t rfalCrcUpdateCcitt(uint16_t crcSeed, uint8_t dataByte)
+{
+    uint16_t crc = crcSeed;
+    uint8_t  dat = dataByte;
+    
+    dat ^= (uint8_t)(crc & 0xFFU);
+    dat ^= (dat << 4);
+
+    crc = (crc >> 8)^(((uint16_t) dat) << 8)^(((uint16_t) dat) << 3)^(((uint16_t) dat) >> 4);
+
+    return crc;
+}
+