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+/*
+ * @brief LPC17xx/40xx Cyclic Redundancy Check (CRC) Engine driver
+ *
+ * @note
+ * Copyright(C) NXP Semiconductors, 2014
+ * All rights reserved.
+ *
+ * @par
+ * Software that is described herein is for illustrative purposes only
+ * which provides customers with programming information regarding the
+ * LPC products.  This software is supplied "AS IS" without any warranties of
+ * any kind, and NXP Semiconductors and its licenser disclaim any and
+ * all warranties, express or implied, including all implied warranties of
+ * merchantability, fitness for a particular purpose and non-infringement of
+ * intellectual property rights.  NXP Semiconductors assumes no responsibility
+ * or liability for the use of the software, conveys no license or rights under any
+ * patent, copyright, mask work right, or any other intellectual property rights in
+ * or to any products. NXP Semiconductors reserves the right to make changes
+ * in the software without notification. NXP Semiconductors also makes no
+ * representation or warranty that such application will be suitable for the
+ * specified use without further testing or modification.
+ *
+ * @par
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation is hereby granted, under NXP Semiconductors' and its
+ * licensor's relevant copyrights in the software, without fee, provided that it
+ * is used in conjunction with NXP Semiconductors microcontrollers.  This
+ * copyright, permission, and disclaimer notice must appear in all copies of
+ * this code.
+ */
+
+#include "chip.h"
+
+#if defined(CHIP_LPC177X_8X) || defined(CHIP_LPC40XX)
+
+/*****************************************************************************
+ * Private types/enumerations/variables
+ ****************************************************************************/
+
+/*****************************************************************************
+ * Public types/enumerations/variables
+ ****************************************************************************/
+
+/*****************************************************************************
+ * Private functions
+ ****************************************************************************/
+
+/*****************************************************************************
+ * Public functions
+ ****************************************************************************/
+
+/* Sets up the CRC engine with defaults based on the polynomial to be used */
+void Chip_CRC_UseDefaultConfig(CRC_POLY_T poly)
+{
+	switch (poly) {
+	case CRC_POLY_CRC16:
+		LPC_CRC->MODE = MODE_CFG_CRC16;
+		LPC_CRC->SEED = CRC_SEED_CRC16;
+		break;
+
+	case CRC_POLY_CRC32:
+		LPC_CRC->MODE = MODE_CFG_CRC32;
+		LPC_CRC->SEED = CRC_SEED_CRC32;
+		break;
+
+	case CRC_POLY_CCITT:
+	default:
+		LPC_CRC->MODE = MODE_CFG_CCITT;
+		LPC_CRC->SEED = CRC_SEED_CCITT;
+		break;
+	}
+}
+
+/* configure CRC engine and compute CCITT checksum from 8-bit data */
+uint32_t Chip_CRC_CRC8(const uint8_t *data, uint32_t bytes)
+{
+	Chip_CRC_UseDefaultConfig(CRC_POLY_CCITT);
+	while (bytes > 0) {
+		Chip_CRC_Write8(*data);
+		data++;
+		bytes--;
+	}
+	return Chip_CRC_Sum();
+}
+
+/* Convenience function for computing a standard CRC16 checksum from 16-bit data block */
+uint32_t Chip_CRC_CRC16(const uint16_t *data, uint32_t hwords)
+{
+	Chip_CRC_UseDefaultConfig(CRC_POLY_CRC16);
+	while (hwords > 0) {
+		Chip_CRC_Write16(*data);
+		data++;
+		hwords--;
+	}
+	return Chip_CRC_Sum();
+}
+
+/* Convenience function for computing a standard CRC32 checksum from 32-bit data block */
+uint32_t Chip_CRC_CRC32(const uint32_t *data, uint32_t words)
+{
+	Chip_CRC_UseDefaultConfig(CRC_POLY_CRC32);
+	while (words > 0) {
+		Chip_CRC_Write32(*data);
+		data++;
+		words--;
+	}
+	return Chip_CRC_Sum();
+}
+
+#endif /* defined(CHIP_LPC177X_8X) || defined(CHIP_LPC40XX) */