LedDisplay.h

/*
  LedDisplay -- controller library for Avago HCMS-297x displays -- version 0.3
  27 Jan 2010 ML: extended a bit to support up to four (4) 8 character displays.
  
   Copyright (c) 2009 Tom Igoe. Some right reserved.
 
   Revisions on version 0.2 and 0.3 by Mark Liebman, 27 Jan 2010
    * extended a bit to support up to four (4) 8 character displays.
  vim: set ts=4:
   
  Controls an Avago HCMS29xx display. This display has 8 characters, each 5x7 LEDs
   
  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA 
  
  Version changes:
  * Version 3 adds support for multiple displays.  Just change the displayLength to 
    the total number of characters (for example, 3 8-character displays, displayLength = 24).

*/


// ensure this library description is only included once
#ifndef LedDisplay_h
#define LedDisplay_h

// supports up to four 8 character displays, connected as documented here,
// under "Multiple Displays" http://playground.arduino.cc/Main/LedDisplay
#define LEDDISPLAY_MAXCHARS  32

// include types & constants of Wiring core API
#if ARDUINO >= 100
#include "Arduino.h"
#else
#include "WProgram.h"
#endif

// Arduino Print library provides print() and println() functionality
#include "Print.h"

// library interface description

class LedDisplay : public Print {
  public:
    // constructor:
   LedDisplay(uint8_t _dataPin,
			  uint8_t _registerSelect,
			  uint8_t _clockPin,
			  uint8_t _chipEnable,
			  uint8_t _resetPin,
			  uint8_t _displayLength);


	// initializer method:
	void begin();

	void clear();						// clear the display
	void home();						// set cursor to far left hand position
	void setCursor(int whichPosition);	// set cursor to any position
	int  getCursor();					// get the cursor position

#if ARDUINO >= 100
	virtual size_t write(uint8_t b);	// write a character to the display and advance cursor
#else
	virtual void write(uint8_t b);		// write a character to the display and advance cursor
#endif
	using Print::write;

	void setString(const char* _stringToDisplay);	// set the displayString variable
	const char * getString();						// get the displayString
	int stringLength();							// get the length of displayString

	void scroll(int direction);			// scroll whatever string is stored in library's displayString variable

	void setBrightness(uint8_t bright);			// set display brightness, 0 - 15

	// Control register setters. for addressing the display directly:
	void loadControlRegister(uint8_t dataByte);
	void loadAllControlRegisters(uint8_t dataByte);
	void loadDotRegister();

    int version(void);							// return library version

  private:
  	// Character display setters:
	void writeCharacter(char whatCharacter, byte whatPosition);	// write a character to a buffer which will
																// be sent to the display by loadDotRegister()

	int cursorPos;				// position of the cursor
	uint8_t dotRegister[LEDDISPLAY_MAXCHARS * 5]; // 5 bytes per character * maxchars

	// Define pins for the LED display:
	uint8_t dataPin;         	// connects to the display's data in
	uint8_t registerSelect;   	// the display's register select pin
	uint8_t clockPin;         	// the display's clock pin
	uint8_t chipEnable;       	// the display's chip enable pin
	uint8_t resetPin;         	// the display's reset pin
	uint8_t displayLength;    	// number of bytes needed to pad the string
	char stringBuffer[LEDDISPLAY_MAXCHARS+1];  // buffer to hold initial display string
	const char * displayString;	// string for scrolling
};

#endif