serialmessage 0.2.0

Pack serial data into a fast, reliable, and packetized form for communicating with e.g. a Microcontroller.
Documentation 
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#pragma once
#include "Arduino.h"


class PacketCRC
{
  public: // <<---------------------------------------//public
	uint8_t poly = 0;


	PacketCRC(const uint8_t& polynomial = 0x9B, const uint8_t& crcLen = 8)
	{
		poly      = polynomial;
		crcLen_   = crcLen;
		tableLen_ = pow(2, crcLen);
		csTable   = new uint8_t[tableLen_];

		generateTable();
	}

	void generateTable()
	{
		for (uint16_t i = 0; i < tableLen_; ++i)
		{
			int curr = i;

			for (int j = 0; j < 8; ++j)
			{
				if ((curr & 0x80) != 0)
					curr = (curr << 1) ^ (int)poly;
				else
					curr <<= 1;
			}

			csTable[i] = (byte)curr;
		}
	}

	void printTable()
	{
		for (uint16_t i = 0; i < tableLen_; i++)
		{
			Serial.print(csTable[i], HEX);

			if ((i + 1) % 16)
				Serial.print(' ');
			else
				Serial.println();
		}
	}

	uint8_t calculate(const uint8_t& val)
	{
		if (val < tableLen_)
			return csTable[val];
		return 0;
	}

	uint8_t calculate(uint8_t arr[], uint8_t len)
	{
		uint8_t crc = 0;
		for (uint16_t i = 0; i < len; i++)
			crc = csTable[crc ^ arr[i]];

		return crc;
	}


  private: // <<---------------------------------------//private
	uint16_t tableLen_;
	uint8_t  crcLen_;
	uint8_t* csTable;
};


extern PacketCRC crc;