From 51ad2f71c765948d33027f6c9d0768003371aace Mon Sep 17 00:00:00 2001
From: "Ben V. Brown" <Ralim@Ralimtek.com>
Date: Tue, 21 Jun 2022 20:51:47 +1000
Subject: [PATCH] crc32

---
 source/Core/BSP/Magic/crc32.h | 29 +++++++++++++++++++++++++++++
 source/Core/Drivers/crc16.cpp | 19 -------------------
 source/Core/Drivers/crc16.hpp |  6 ------
 3 files changed, 29 insertions(+), 25 deletions(-)
 create mode 100644 source/Core/BSP/Magic/crc32.h
 delete mode 100644 source/Core/Drivers/crc16.cpp
 delete mode 100644 source/Core/Drivers/crc16.hpp

diff --git a/source/Core/BSP/Magic/crc32.h b/source/Core/BSP/Magic/crc32.h
new file mode 100644
index 00000000..c8bc9c09
--- /dev/null
+++ b/source/Core/BSP/Magic/crc32.h
@@ -0,0 +1,29 @@
+#pragma once
+
+#include <stdint.h>
+
+#define DEFAULT_POLY 0x973afb51
+
+template <uint32_t polynomial = DEFAULT_POLY> struct CRC32Table {
+  constexpr CRC32Table() : table() {
+    for (uint32_t i = 0; i < 256; i++) {
+      uint32_t c = i;
+      for (auto j = 0; j < 8; j++) {
+        if (c & 1) {
+          c = polynomial ^ (c >> 1);
+        } else {
+          c >>= 1;
+        }
+      }
+      table[i] = c;
+    }
+  }
+  uint32_t table[256];
+  uint32_t computeCRC32(uint32_t initial, const uint8_t *buf, int len) {
+    uint32_t c = initial ^ 0xFFFFFFFF;
+    for (auto i = 0; i < len; ++i) {
+      c = table[(c ^ buf[i]) & 0xFF] ^ (c >> 8);
+    }
+    return c ^ 0xFFFFFFFF;
+  }
+};
diff --git a/source/Core/Drivers/crc16.cpp b/source/Core/Drivers/crc16.cpp
deleted file mode 100644
index 9966c9f0..00000000
--- a/source/Core/Drivers/crc16.cpp
+++ /dev/null
@@ -1,19 +0,0 @@
-
-#include "crc16.hpp"
-#define POLYNOM 0x8005
-unsigned int crc16(unsigned int crcValue, unsigned char newByte) {
-  unsigned char i;
-
-  for (i = 0; i < 8; i++) {
-
-    if (((crcValue & 0x8000) >> 8) ^ (newByte & 0x80)) {
-      crcValue = (crcValue << 1) ^ POLYNOM;
-    } else {
-      crcValue = (crcValue << 1);
-    }
-
-    newByte <<= 1;
-  }
-
-  return crcValue;
-}
\ No newline at end of file
diff --git a/source/Core/Drivers/crc16.hpp b/source/Core/Drivers/crc16.hpp
deleted file mode 100644
index b598c6fb..00000000
--- a/source/Core/Drivers/crc16.hpp
+++ /dev/null
@@ -1,6 +0,0 @@
-#ifndef DRIVERS_CRC16_H_
-#define DRIVERS_CRC16_H_
-
-unsigned int crc16(unsigned int crcValue, unsigned char newByte);
-
-#endif
\ No newline at end of file