LCD Library 1.2.0
LCD Library - LCD control class hierarchy library. Drop in replacement for the LiquidCrystal Library.
/Users/fmalpartida/development/ardWorkspace/LiquidCrystal_I2C/LiquiCrystal_I2C/LiquidCrystal_SR.h
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00001 // ---------------------------------------------------------------------------
00002 // Created by Francisco Malpartida on 20/08/11.
00003 // Copyright 2011 - Under creative commons license 3.0:
00004 //        Attribution-ShareAlike CC BY-SA
00005 //
00006 // This software is furnished "as is", without technical support, and with no 
00007 // warranty, express or implied, as to its usefulness for any purpose.
00008 //
00009 // Thread Safe: No
00010 // Extendable: Yes
00011 //
00012 // @file LiquidCrystal_SR.h
00013 //  Connects an LCD using 2 or 3 pins from the Arduino, via an 8-bit 
00014 // ShiftRegister (SR from now on).
00015 // 
00016 // @brief 
00017 // This is a port of the ShiftRegLCD library from raron and ported to the
00018 // LCD library.
00019 //
00020 // The functionality provided by this class and its base class is identical
00021 // to the original functionality of the Arduino LiquidCrystal library and can
00022 // be used as such.
00023 //
00024 // Modified to work serially with the shiftOut() function, an 8-bit
00025 // unlatched, no-tristate, unidirectional SIPO (Serial-In-Parallel-Out)
00026 // shift register (IE a very simple SR), and an LCD in 4-bit mode.
00027 // Any such shift register should do (pref. 74LS family IC's for 2-wire).
00028 // I used 74LS164, for the reason that's what I had at hand.
00029 //
00030 // Connection description:
00031 //
00032 // SR output:
00033 // Bit  #0   - N/C - not connected, used to hold a zero
00034 // Bit  #1   - N/C
00035 // Bit  #2   - connects to RS (Register Select) on the LCD
00036 // Bits #3-6 - connects to LCD data inputs D4 - D7.
00037 // Bit  #7   - enables the LCD enable-puls (via the diode-resistor AND "gate")
00038 //
00039 // 2 or 3 Pins required from the Arduino for Data, Clock and (optional) Enable
00040 // If not using Enable, the Data pin is used for the enable signal by defining
00041 // the same pin for Enable as for Data. Data and Clock outputs/pins goes to
00042 // the shiftregister.
00043 // LCD RW-pin hardwired to LOW (only writing to LCD).
00044 // Busy Flag (BF, data bit D7) is not read.
00045 //
00046 //  Original project homepage: http://code.google.com/p/arduinoshiftreglcd/
00047 //
00048 //
00049 // History
00050 // 2011.10.29  fmalpartida - adaption of the library to the LCD class hierarchy.
00051 // 2011.07.02  Fixed a minor flaw in setCursor function. No functional change, 
00052 //             just a bit more memory efficient.
00053 //             Thanks to CapnBry (from google code and github) who noticed it.
00054 //             URL to his version of shiftregLCD:
00055 //             https://github.com/CapnBry/HeaterMeter/commit/c6beba1b46b092ab0b33bcbd0a30a201fd1f28c1
00056 // 2009.07.30  raron - minor corrections to the comments.
00057 //             Fixed timing to datasheet safe. Fixed keyword highlights.
00058 // 2009.07.28  Mircho / raron - a new modification to the schematics, and a
00059 //             more streamlined interface
00060 // 2009.07.27  Thanks to an excellent suggestion from mircho at the Arduiono 
00061 //             playgrond forum, the number of wires now required is only two!
00062 // 2009.07.25  raron - Fixed comments. I really messed up the comments before 
00063 //             posting this, so I had to fix it.
00064 //             Renamed a function, but no improvements or functional changes.
00065 // 2009.07.23  Incorporated some proper initialization routines
00066 //             inspired (lets say copy-paste-tweaked) from LiquidCrystal
00067 //             library improvements from LadyAda.
00068 // 2009.05.23  raron - first version, but based mostly (as in almost verbatim)
00069 //             on the "official" LiquidCrystal library.
00070 //
00071 //
00072 //
00073 // @author F. Malpartida - fmalpartida@gmail.com
00074 // ---------------------------------------------------------------------------
00075 #ifndef _LIQUIDCRYSTAL_SR_
00076 #define _LIQUIDCRYSTAL_SR_
00077 
00078 #include <inttypes.h>
00079 #include "LCD.h"
00080 #include "FastIO.h"
00081 
00082 
00083 // two-wire indicator constant
00084 // ---------------------------------------------------------------------------
00085 #define TWO_WIRE  204
00086 #define SR_RS_BIT 0x04
00087 #define SR_EN_BIT 0x80
00088 
00089 class LiquidCrystal_SR : public LCD
00090 {
00091 public:
00103    LiquidCrystal_SR ( uint8_t srdata, uint8_t srclock, uint8_t enable );
00104    
00117    virtual void send(uint8_t value, uint8_t mode);
00118    
00128    void setBacklight ( uint8_t mode );
00129    
00137    void setBacklightPin ( uint8_t pin );
00138    
00139    
00140    
00141 private:
00142    
00148    void init ( uint8_t srdata, uint8_t srclock, uint8_t enable, uint8_t lines, 
00149               uint8_t font );
00150    
00155    void shiftIt (uint8_t val);
00156 
00157    uint8_t _enable_pin;  // Enable Pin
00158    uint8_t _two_wire;    // two wire mode
00159 
00160    fio_register _srDataRegister; // Serial Data pin
00161    fio_bit _srDataBit;
00162    fio_register _srClockRegister; // Clock Pin
00163    fio_bit _srClockBit;
00164    fio_register _srEnableRegister; // Enable Pin
00165    fio_bit _srEnableBit;
00166 
00167 };
00168 
00169 #endif
00170 
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