203 lines
8.0 KiB
C++
203 lines
8.0 KiB
C++
// ---------------------------------------------------------------------------
|
|
// Created by Francisco Malpartida on 7.3.2012.
|
|
// Copyright 2011 - Under creative commons license 3.0:
|
|
// Attribution-ShareAlike CC BY-SA
|
|
//
|
|
// This software is furnished "as is", without technical support, and with no
|
|
// warranty, express or implied, as to its usefulness for any purpose.
|
|
//
|
|
// Thread Safe: No
|
|
// Extendable: Yes
|
|
//
|
|
// @file LiquidCrystal_SR3W.h
|
|
// This file implements a basic liquid crystal library that comes as standard
|
|
// in the Arduino SDK but using a generic SHIFT REGISTER extension board.
|
|
//
|
|
// @brief
|
|
// This is a basic implementation of the LiquidCrystal library of the
|
|
// Arduino SDK. The original library has been reworked in such a way that
|
|
// this class implements the all methods to command an LCD based
|
|
// on the Hitachi HD44780 and compatible chipsets using a 3 wire latching
|
|
// shift register. While it has been tested with a 74HC595N shift register
|
|
// it should also work with other latching shift registers such as the MC14094
|
|
// and the HEF4094
|
|
//
|
|
// This particular driver has been created as generic as possible to enable
|
|
// users to configure and connect their LCDs using just 3 digital IOs from the
|
|
// AVR or Arduino, and connect the LCD to the outputs of the shiftregister
|
|
// in any configuration. The library is configured by passing the IO pins
|
|
// that control the strobe, data and clock of the shift register and a map
|
|
// of how the shiftregister is connected to the LCD.
|
|
//
|
|
//
|
|
// +--------------------------------------------+
|
|
// | MCU |
|
|
// | IO1 IO2 IO3 |
|
|
// +----+-------------+-------------+-----------+
|
|
// | | |
|
|
// | | |
|
|
// +----+-------------+-------------+-----------+
|
|
// | Strobe Data Clock |
|
|
// | 8-bit shift/latch register | 74HC595N
|
|
// | Qa0 Qb1 Qc2 Qd3 Qe4 Qf5 Qg6 Qh7 |
|
|
// +----+----+----+----+----+----+----+----+----+
|
|
// | | | | | | |
|
|
// |11 |12 |13 |14 |6 |5 |4 (LCD pins)
|
|
// +----+----+----+----+----+----+----+----+----+
|
|
// | DB4 DB5 DB6 DB7 E Rw RS |
|
|
// | LCD Module |
|
|
//
|
|
// NOTE: Rw is not used by the driver so it can be connected to GND.
|
|
//
|
|
// The functionality provided by this class and its base class is identical
|
|
// to the original functionality of the Arduino LiquidCrystal library.
|
|
//
|
|
//
|
|
// @author F. Malpartida - fmalpartida@gmail.com
|
|
// ---------------------------------------------------------------------------
|
|
#ifndef _LIQUIDCRYSTAL_SR3W_H_
|
|
#define _LIQUIDCRYSTAL_SR3W_H_
|
|
|
|
#include <inttypes.h>
|
|
#include "LCD.h"
|
|
#include "FastIO.h"
|
|
|
|
|
|
class LiquidCrystal_SR3W : public LCD
|
|
{
|
|
public:
|
|
|
|
/*!
|
|
@method
|
|
@abstract Class constructor.
|
|
@discussion Initializes class variables and defines the IO driving the
|
|
shift register. The constructor does not initialize the LCD.
|
|
Default configuration:
|
|
Shift register LCD
|
|
QA - 0 DB4
|
|
QB - 1 DB5
|
|
QC - 2 DB6
|
|
QD - 3 DB7
|
|
QE - 4 E
|
|
QF - 5
|
|
QG - 6 Rs
|
|
GND Rw
|
|
|
|
@param strobe[in] digital IO connected to shiftregister strobe pin.
|
|
@param data[in] digital IO connected to the shiftregister data pin.
|
|
@param clk[in] digital IO connected to the shiftregister clock pin.
|
|
*/
|
|
LiquidCrystal_SR3W(uint8_t data, uint8_t clk, uint8_t strobe);
|
|
// Constructor with backlight control
|
|
LiquidCrystal_SR3W(uint8_t data, uint8_t clk, uint8_t strobe,
|
|
uint8_t backlighPin, t_backlighPol pol);
|
|
|
|
/*!
|
|
@method
|
|
@abstract Class constructor.
|
|
@discussion Initializes class variables and defines the control lines of
|
|
the LCD and the shiftregister. The constructor does not initialize the LCD.
|
|
|
|
@param strobe[in] digital IO connected to shiftregister strobe pin.
|
|
@param data[in] digital IO connected to shiftregister data pin.
|
|
@param clk[in] digital IO connected to shiftregister clock pin.
|
|
@param En[in] LCD En (Enable) pin connected to SR output pin.
|
|
@param Rw[in] LCD Rw (Read/write) pin connected to SR output pin.
|
|
@param Rs[in] LCD Rs (Reg Select) pin connected to SR output pin.
|
|
@param d4[in] LCD data 4 pin map to the SR output pin.
|
|
@param d5[in] LCD data 5 pin map to the SR output pin.
|
|
@param d6[in] LCD data 6 pin map to the SR output pin.
|
|
@param d7[in] LCD data 7 pin map to the SR output pin.
|
|
*/
|
|
LiquidCrystal_SR3W(uint8_t data, uint8_t clk, uint8_t strobe,
|
|
uint8_t En, uint8_t Rw, uint8_t Rs,
|
|
uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7 );
|
|
// Constructor with backlight control
|
|
LiquidCrystal_SR3W( uint8_t data, uint8_t clk, uint8_t strobe,
|
|
uint8_t En, uint8_t Rw, uint8_t Rs,
|
|
uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7,
|
|
uint8_t backlighPin, t_backlighPol pol);
|
|
|
|
/*!
|
|
@function
|
|
@abstract Send a particular value to the LCD.
|
|
@discussion Sends a particular value to the LCD for writing to the LCD or
|
|
as an LCD command.
|
|
|
|
Users should never call this method.
|
|
|
|
@param value[in] Value to send to the LCD.
|
|
@param mode[in] DATA - write to the LCD CGRAM, COMMAND - write a
|
|
command to the LCD.
|
|
*/
|
|
virtual void send(uint8_t value, uint8_t mode);
|
|
|
|
/*!
|
|
@function
|
|
@abstract Sets the pin to control the backlight.
|
|
@discussion Sets the pin in the device to control the backlight. This device
|
|
doesn't support dimming backlight capability.
|
|
|
|
@param 0: backlight off, 1..255: backlight on.
|
|
*/
|
|
void setBacklightPin ( uint8_t value, t_backlighPol pol );
|
|
|
|
/*!
|
|
@function
|
|
@abstract Switch-on/off the LCD backlight.
|
|
@discussion Switch-on/off the LCD backlight.
|
|
The setBacklightPin has to be called before setting the backlight for
|
|
this method to work. @see setBacklightPin.
|
|
|
|
@param value: backlight mode (HIGH|LOW)
|
|
*/
|
|
void setBacklight ( uint8_t value );
|
|
|
|
private:
|
|
|
|
/*!
|
|
@method
|
|
@abstract Initializes the LCD class
|
|
@discussion Initializes the LCD class and IO expansion module.
|
|
*/
|
|
int init(uint8_t data, uint8_t clk, uint8_t strobe,
|
|
uint8_t Rs, uint8_t Rw, uint8_t En,
|
|
uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7);
|
|
|
|
/*!
|
|
@method
|
|
@abstract Writes an 4 bit value to the LCD.
|
|
@discussion Writes 4 bits (the least significant) to the LCD control data lines.
|
|
@param value[in] Value to write to the LCD
|
|
@param more[in] Value to distinguish between command and data.
|
|
COMMAND == command, DATA == data.
|
|
*/
|
|
void write4bits(uint8_t value, uint8_t mode);
|
|
|
|
/*!
|
|
@function
|
|
@abstract load into the shift register a byte
|
|
@discussion loads into the shift register a byte
|
|
@param value[in]: value to be loaded into the shiftregister.
|
|
*/
|
|
void loadSR(uint8_t value);
|
|
|
|
|
|
fio_bit _strobe; // shift register strobe pin
|
|
fio_register _strobe_reg; // SR strobe pin MCU register
|
|
fio_bit _data; // shift register data pin
|
|
fio_register _data_reg; // SR data pin MCU register
|
|
fio_bit _clk; // shift register clock pin
|
|
fio_register _clk_reg; // SR clock pin MCU register
|
|
uint8_t _En; // LCD expander word for enable pin
|
|
uint8_t _Rw; // LCD expander word for R/W pin
|
|
uint8_t _Rs; // LCD expander word for Register Select pin
|
|
uint8_t _data_pins[4]; // LCD data lines
|
|
uint8_t _backlightPinMask; // Backlight IO pin mask
|
|
uint8_t _backlightStsMask; // Backlight status mask
|
|
|
|
};
|
|
|
|
#endif
|
|
|