Add CRC classes CRC8, CRC16, CRC32, CRC64 (#3)

* version 0.1.1
RobTillaart · Jan 20, 2021 · 783d437 · 783d437
1 parent 2dac155
commit 783d437
Show file tree

Hide file tree

Showing 21 changed files with 1,040 additions and 133 deletions.
diff --git a/CRC.h b/CRC.h
@@ -2,17 +2,16 @@
 //
 //    FILE: CRC.h
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.1.0
+// VERSION: 0.1.1
 // PURPOSE: Arduino library fir CRC8, CRC16, CRC16-CCITT, CRC32
 //     URL: https://github.com/RobTillaart/CRC
 //
 
 
-
 #include "Arduino.h"
 
 
-#define CRC_LIB_VERSION       (F("0.1.0"))
+#define CRC_LIB_VERSION       (F("0.1.1"))
 
 
 ////////////////////////////////////////////////////////////////
@@ -68,7 +67,7 @@ uint64_t reverse64(uint64_t in)
 ///////////////////////////////////////////////////////////////////////////////////
 
 // CRC POLYNOME = x8 + x5 + x4 + 1 = 1001 1000 = 0x8C
-uint8_t CRC8(uint8_t *array, uint8_t length, uint8_t polynome = 0xD5, uint8_t startmask = 0x00, uint8_t endmask = 0x00, bool reverseIn = false, bool reverseOut = false)
+uint8_t crc8(uint8_t *array, uint8_t length, uint8_t polynome = 0xD5, uint8_t startmask = 0x00, uint8_t endmask = 0x00, bool reverseIn = false, bool reverseOut = false)
 {
   uint8_t crc = startmask;
   while (length--) 
@@ -96,7 +95,7 @@ uint8_t CRC8(uint8_t *array, uint8_t length, uint8_t polynome = 0xD5, uint8_t st
 
 
 // CRC POLYNOME = x15 + 1 =  1000 0000 0000 0001 = 0x8001
-uint16_t CRC16(uint8_t *array, uint8_t length, uint16_t polynome = 0x8001, uint16_t startmask = 0x0000, uint16_t endmask = 0x0000, bool reverseIn = false, bool reverseOut = false)
+uint16_t crc16(uint8_t *array, uint8_t length, uint16_t polynome = 0x8001, uint16_t startmask = 0x0000, uint16_t endmask = 0x0000, bool reverseIn = false, bool reverseOut = false)
 {
   uint16_t crc = startmask;
   while (length--) 
@@ -124,14 +123,14 @@ uint16_t CRC16(uint8_t *array, uint8_t length, uint16_t polynome = 0x8001, uint1
 
 
 // CRC-CCITT POLYNOME = x13 + X5 + 1 =  0001 0000 0010 0001 = 0x1021
-uint16_t CRC16_CCITT(uint8_t *array, uint8_t length)
+uint16_t crc16_CCITT(uint8_t *array, uint8_t length)
 {
-  return CRC16(array, length, 0x1021, 0xFFFF);
+  return crc16(array, length, 0x1021, 0xFFFF);
 }
 
 
 // CRC-32 POLYNOME =  x32 + ..... + 1
-uint32_t CRC32(uint8_t *array, uint8_t length, uint32_t polynome = 0x04C11DB7, uint32_t startmask = 0, uint32_t endmask = 0, bool reverseIn = false, bool reverseOut = false)
+uint32_t crc32(uint8_t *array, uint8_t length, uint32_t polynome = 0x04C11DB7, uint32_t startmask = 0, uint32_t endmask = 0, bool reverseIn = false, bool reverseOut = false)
 {
   uint32_t crc = startmask;
   while (length--) 
@@ -159,7 +158,7 @@ uint32_t CRC32(uint8_t *array, uint8_t length, uint32_t polynome = 0x04C11DB7, u
 
 
 // CRC-CCITT POLYNOME =  x64 + ..... + 1
-uint64_t CRC64(uint8_t *array, uint8_t length, uint64_t polynome, uint64_t startmask, uint64_t endmask, bool reverseIn, bool reverseOut)
+uint64_t crc64(uint8_t *array, uint8_t length, uint64_t polynome, uint64_t startmask, uint64_t endmask, bool reverseIn, bool reverseOut)
 {
   uint64_t crc = startmask;
   while (length--) 
@@ -185,7 +184,5 @@ uint64_t CRC64(uint8_t *array, uint8_t length, uint64_t polynome, uint64_t start
   return crc;
 }
 
-///////////////////////////////////////////////////////////////
-
 
 // -- END OF FILE --
diff --git a/CRC16.cpp b/CRC16.cpp
@@ -0,0 +1,96 @@
+//
+//    FILE: CRC16.cpp
+//  AUTHOR: Rob Tillaart
+// PURPOSE: Arduino class for CRC16
+//     URL: https://github.com/RobTillaart/CRC
+
+
+#include "CRC16.h"
+
+
+CRC16::CRC16()
+{
+  reset();
+}
+
+
+void CRC16::reset()
+{
+  _polynome   = CRC16_DEFAULT_POLYNOME;
+  _startMask  = 0;
+  _endMask    = 0;
+  _crc        = 0;
+  _reverseIn  = false;
+  _reverseOut = false;
+  _started    = false;
+  _count      = 0;
+}
+
+
+void CRC16::restart()
+{
+  _started = true;
+  _crc     = _startMask;
+  _count   = 0;
+}
+
+
+void CRC16::add(uint8_t value)
+{
+  _count++;
+  _update(value);
+}
+
+
+void CRC16::add(uint8_t * array, uint32_t length)
+{
+  _count += length;
+  while (length--)
+  {
+    yield();
+    uint8_t data = *array++;
+    _update(data);
+  }
+}
+
+
+uint16_t CRC16::getCRC()
+{
+  uint16_t rv = _crc;
+  if (_reverseOut) rv = _reverse(rv);
+  rv ^= _endMask;
+  return rv;
+}
+
+
+void CRC16::_update(uint8_t value)
+{
+  if (!_started) restart();
+  if (_reverseIn) value = _reverse(value);
+  _crc ^= ((uint16_t)value) << 8;;
+  for (uint8_t i = 8; i; i--) 
+  {
+    if (_crc & (1UL << 15))
+    {
+      _crc <<= 1;
+      _crc ^= _polynome;
+    }
+    else
+    {
+      _crc <<= 1;
+    }
+  }
+}
+
+
+uint16_t CRC16::_reverse(uint16_t in)
+{
+  uint16_t x = in;
+  x = (((x & 0XAAAA) >> 1) | ((x & 0X5555) << 1));
+  x = (((x & 0xCCCC) >> 2) | ((x & 0X3333) << 2));
+  x = (((x & 0xF0F0) >> 4) | ((x & 0X0F0F) << 4));
+  x = (( x >> 8) | (x << 8));
+  return x;
+}
+
+// -- END OF FILE --
diff --git a/CRC16.h b/CRC16.h
@@ -0,0 +1,50 @@
+#pragma once
+//
+//    FILE: CRC16.h
+//  AUTHOR: Rob Tillaart
+// PURPOSE: Arduino class for CRC16
+//     URL: https://github.com/RobTillaart/CRC
+
+
+#include "Arduino.h"
+
+#define CRC16_DEFAULT_POLYNOME      0x1021
+
+
+class CRC16
+{
+public:
+  CRC16();
+
+  // set parameters to default
+  void     reset();       // set all to constructor defaults
+  void     restart();     // reset crc with same parameters.
+
+  // set parameters
+  void     setPolynome(uint16_t polynome) { _polynome = polynome; };
+  void     setStartXOR(uint16_t start)    { _startMask = start; };
+  void     setEndXOR(uint16_t end)        { _endMask = end; };
+  void     setReverseIn(bool reverseIn)   { _reverseIn = reverseIn; };
+  void     setReverseOut(bool reverseOut) { _reverseOut = reverseOut; };
+
+  void     add(uint8_t value);
+  void     add(uint8_t * array, uint32_t length);
+
+  uint16_t getCRC();  // returns CRC
+  uint32_t count()    { return _count; };
+
+private:
+  uint16_t _reverse(uint16_t value);
+  void     _update(uint8_t value);
+
+  uint16_t _polynome;
+  uint16_t _startMask;
+  uint16_t _endMask;
+  uint16_t _crc;
+  bool     _reverseIn;
+  bool     _reverseOut;
+  bool     _started;
+  uint32_t _count;
+};
+
+// -- END OF FILE --
diff --git a/CRC32.cpp b/CRC32.cpp
@@ -0,0 +1,96 @@
+//
+//    FILE: CRC32.cpp
+//  AUTHOR: Rob Tillaart
+// PURPOSE: Arduino class for CRC32;
+//     URL: https://github.com/RobTillaart/CRC
+
+
+#include "CRC32.h"
+
+
+CRC32::CRC32()
+{
+  reset();
+}
+
+
+void CRC32::reset()
+{
+  _polynome   = CRC32_DEFAULT_POLYNOME;
+  _startMask  = 0;
+  _endMask    = 0;
+  _crc        = 0;
+  _reverseIn  = false;
+  _reverseOut = false;
+  _started    = false;
+  _count      = 0;
+}
+
+
+void CRC32::restart()
+{
+  _started = true;
+  _crc     = _startMask;
+  _count   = 0;
+}
+
+
+void CRC32::add(uint8_t value)
+{
+  _count++;
+  _update(value);
+}
+
+
+void CRC32::add(uint8_t * array, uint32_t length)
+{
+  _count += length;
+  while (length--)
+  {
+    yield();
+    _update(*array++);
+  }
+}
+
+
+uint32_t CRC32::getCRC()
+{
+  uint32_t rv = _crc;
+  if (_reverseOut) rv = _reverse(rv);
+  rv ^=_endMask;
+  return rv;
+}
+
+
+void CRC32::_update(uint8_t value)
+{
+  if (!_started) restart();
+  if (_reverseIn) value = _reverse(value);
+  _crc ^= ((uint32_t)value) << 24;;
+  for (uint8_t i = 8; i; i--) 
+  {
+    if (_crc & (1UL << 31))
+    {
+      _crc <<= 1;
+      _crc ^= _polynome;
+    }
+    else
+    {
+      _crc <<= 1;
+    }
+  }
+}
+
+
+uint32_t CRC32::_reverse(uint32_t in)
+{
+  uint32_t x = in;
+  x = (((x & 0xAAAAAAAA) >> 1)  | ((x & 0x55555555) << 1));
+  x = (((x & 0xCCCCCCCC) >> 2)  | ((x & 0x33333333) << 2));
+  x = (((x & 0xF0F0F0F0) >> 4)  | ((x & 0x0F0F0F0F) << 4));
+  x = (((x & 0xFF00FF00) >> 8)  | ((x & 0x00FF00FF) << 8));
+  x = (x >> 16) | (x << 16);
+  return x;
+}
+
+// -- END OF FILE --
diff --git a/CRC32.h b/CRC32.h
@@ -0,0 +1,50 @@
+#pragma once
+//
+//    FILE: CRC32.h
+//  AUTHOR: Rob Tillaart
+// PURPOSE: Arduino class for CRC32
+//     URL: https://github.com/RobTillaart/CRC
+
+
+#include "Arduino.h"
+
+#define CRC32_DEFAULT_POLYNOME      0x04C11DB7
+
+
+class CRC32
+{
+public:
+  CRC32();
+
+  // set parameters to default
+  void     reset();       // set all to constructor defaults
+  void     restart();     // reset crc with same parameters.
+
+  // set parameters
+  void     setPolynome(uint32_t polynome) { _polynome = polynome; };
+  void     setStartXOR(uint32_t start)    { _startMask = start; };
+  void     setEndXOR(uint32_t end)        { _endMask = end; };
+  void     setReverseIn(bool reverseIn)   { _reverseIn = reverseIn; };
+  void     setReverseOut(bool reverseOut) { _reverseOut = reverseOut; };
+
+  void     add(uint8_t value);
+  void     add(uint8_t * array, uint32_t length);
+
+  uint32_t getCRC();  // returns CRC
+  uint32_t count()    { return _count; };
+
+private:
+  uint32_t _reverse(uint32_t value);
+  void     _update(uint8_t value);
+
+  uint32_t _polynome;
+  uint32_t _startMask;
+  uint32_t _endMask;
+  uint32_t _crc;
+  bool     _reverseIn;
+  bool     _reverseOut;
+  bool     _started;
+  uint32_t _count;
+};
+
+// -- END OF FILE --