first commit
This commit is contained in:
Jérôme Delacotte
271
libraries/hd44780/hd44780ioClass/hd44780_I2Clcd.h
Normal file
271
libraries/hd44780/hd44780ioClass/hd44780_I2Clcd.h
Normal file
@@ -0,0 +1,271 @@
|
||||
// vi:ts=4
|
||||
// ---------------------------------------------------------------------------
|
||||
// hd44780_I2Clcd.h - hd44780_I2Clcd i/o subclass for hd44780 library
|
||||
// Copyright (c) 2013-2020 Bill Perry
|
||||
//
|
||||
// The API functionality provided by this library class is compatible
|
||||
// with the API functionality of the Arduino LiquidCrystal library.
|
||||
//
|
||||
// ---------------------------------------------------------------------------
|
||||
//
|
||||
// This file is part of the hd44780 library
|
||||
//
|
||||
// hd44780_I2Clcd is free software: you can redistribute it and/or modify
|
||||
// it under the terms of the GNU General Public License as published by
|
||||
// the Free Software Foundation version 3 of the License.
|
||||
//
|
||||
// hd44780_I2Clcd 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 General Public License for more details.
|
||||
//
|
||||
// You should have received a copy of the GNU General Public License
|
||||
// along with hd44780_I2Clcd. If not, see <http://www.gnu.org/licenses/>.
|
||||
//
|
||||
// ---------------------------------------------------------------------------
|
||||
//
|
||||
// It implements all the hd44780 library i/o methods to control an LCD based
|
||||
// on the Hitachi HD44780 and compatible chipsets which have
|
||||
// a native I2C interface rather than use a simple I2C i/o expander chip
|
||||
// such as a PCF8574 or MCP23008
|
||||
//
|
||||
// Here is a example of such a device:
|
||||
// https://seeeddoc.github.io/Grove-LCD_RGB_Backlight/res/JHD1214Y_YG_1.0.pdf
|
||||
// This device uses address 0x3E and incorrectly responds to read requests
|
||||
// It overlaps with the addresses for the PCF8574A
|
||||
// It will lock up module and/or the AVR i2c h/w and require a power cycle to reset.
|
||||
// NOTE:
|
||||
// This device needs pullups on the bus signals.
|
||||
// While it will usually work on an AVR platform without external pullups,
|
||||
// it doesn't always work.
|
||||
//
|
||||
// PCF2119x chips use this protocol and slave addresses are 0x3A and 0x3B
|
||||
// This is defined in the allocated i2c address table Group 7
|
||||
// It overlaps with the addresses for the PCF8574A
|
||||
// This device has extended function set commands that are not directly
|
||||
// supported by the library but can be used through the command() API
|
||||
//
|
||||
// PCF2116 chips use this protocol and slave addresses are 0x3A and 0x3B
|
||||
// It overlaps with the addresses for the PCF8574A
|
||||
//
|
||||
// Raystar RC1602B5-LLH-JWV is jumper settable to 0x3c, 0x3d, 0x3e, 0x3f
|
||||
// and appears to only be able to be written to.
|
||||
// It overlaps with the addresses for the PCF8574A
|
||||
//
|
||||
// Known addresses for this type of device:
|
||||
// 0x3a PCF2116/PCF2119x
|
||||
// 0x3b PCF2116/PCF2119x
|
||||
// 0x3c Raystar
|
||||
// 0x3d Raystar
|
||||
// 0x3e Raystar
|
||||
// 0x3f Raystar
|
||||
//
|
||||
// The interface consists of sending 2 bytes over I2C for each hd44780
|
||||
// data/cmd.
|
||||
// The first byte is a control byte which sets the RS signal
|
||||
// The second byte is the data.
|
||||
//
|
||||
// The I2C can only control the LCD and does not have the capability
|
||||
// to control the backlight so the backlight will always remain on.
|
||||
//
|
||||
// Attempting to read from some of these devices will lockup the AVR Wire
|
||||
// library.
|
||||
//
|
||||
// 2018.08.06 bperrybap - removed TinyWireM work around (TinyWireM was fixed)
|
||||
// 2017.05.12 bperrybap - now requires IDE 1.0.1 or newer
|
||||
// This is to work around TinyWireM library bugs
|
||||
// 2016.12.26 bperrybap - added auto i2c address location
|
||||
// 2016.09.08 bperrybap - changed param order of iowrite() to match ioread()
|
||||
// 2016.08.06 bperrybap - changed iosend() to iowrite()
|
||||
// 2016.07.27 bperrybap - added return status for iosend()
|
||||
// 2017.07.21 bperrybap - merged all class code into header
|
||||
// 2017.07.20 bperrybap - merged into hd44780 library
|
||||
// 2016.06.09 bperrybap - changed name to hd44780_I2Clcd
|
||||
// 2016.06.08 bperrybap - removed pre IDE 1.0 support
|
||||
// 2016.06.03 bperrybap - added smart execution delays
|
||||
// 2014.02.15 bperrybap - changed to use hd44780 base class library
|
||||
// 2013.06.01 bperrybap - initial creation (hd44780_IIClcd)
|
||||
//
|
||||
// @author Bill Perry - bperrybap@opensource.billsworld.billandterrie.com
|
||||
//
|
||||
// ---------------------------------------------------------------------------
|
||||
#ifndef hd44780_I2Clcd_h
|
||||
#define hd44780_I2Clcd_h
|
||||
|
||||
// A bug in TinyWireM is that requestFrom() returns incorrect status
|
||||
// so its return status can't be used. Instead the code will check the return
|
||||
// from Wire.read() which will return -1 if there no data was transfered.
|
||||
|
||||
#if (ARDUINO < 101) && !defined(MPIDE)
|
||||
#error hd44780_I2Clcd i/o class requires Arduino 1.0.1 or later
|
||||
#endif
|
||||
|
||||
class hd44780_I2Clcd : public hd44780
|
||||
{
|
||||
public:
|
||||
// ====================
|
||||
// === constructors ===
|
||||
// ====================
|
||||
|
||||
hd44780_I2Clcd(uint8_t i2c_addr=0) : _Addr(i2c_addr) {} // zero addres means auto locate
|
||||
|
||||
private:
|
||||
// ====================
|
||||
// === private data ===
|
||||
// ====================
|
||||
|
||||
// Control byte bit values
|
||||
|
||||
// RS signal in HD44780 interface
|
||||
// set for data writes, clear for cmds
|
||||
// note: some datasheets call this A0 bit
|
||||
static const uint8_t I2Clcd_RS = (1 << 6);
|
||||
|
||||
// set if another control byte following data
|
||||
// clear if last control byte
|
||||
static const uint8_t I2Clcd_CO = (1 << 7);
|
||||
|
||||
uint8_t _Addr; // I2C Address of the LCD
|
||||
|
||||
// ==================================================
|
||||
// === hd44780 i/o subclass virtual i/o functions ===
|
||||
// ==================================================
|
||||
//
|
||||
// Note:
|
||||
// It is not possible to control the backlight nor
|
||||
// is it possible to read from the device.
|
||||
// so iosetbacklight() and ioread()
|
||||
// will not be defined and will use the defaults in
|
||||
// hd44780
|
||||
|
||||
// ioinit() - Returns non zero if initialization failed.
|
||||
int ioinit()
|
||||
{
|
||||
int status;
|
||||
|
||||
/*
|
||||
* First, initialize the i2c (Wire) library.
|
||||
* This really shouldn't be here
|
||||
* because Wire.begin() should only be called once, but
|
||||
* unfortunately, there is no way to know if anybody
|
||||
* else has called this.
|
||||
* I believe that it is unreasonable to require the the user
|
||||
* sketch code to do it, because all that should change between
|
||||
* interfaces should be the constructor
|
||||
* So we go ahead and call it here.
|
||||
*/
|
||||
Wire.begin();
|
||||
|
||||
/*
|
||||
* If i2c address was not specified go try to locate device
|
||||
*/
|
||||
if(!_Addr)
|
||||
{
|
||||
if( !(_Addr = LocateDevice())) // failed to find device
|
||||
{
|
||||
return(hd44780::RV_ENXIO);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Check to see if the device is responding
|
||||
*/
|
||||
Wire.beginTransmission(_Addr);
|
||||
if( (status = Wire.endTransmission()) )
|
||||
{
|
||||
if(status == 1)
|
||||
status = hd44780::RV_EMSGSIZE;
|
||||
else if(status == 2)
|
||||
status = hd44780::RV_ENXIO;
|
||||
else
|
||||
status = hd44780::RV_EIO;
|
||||
}
|
||||
|
||||
/*
|
||||
* this device only runs in 8 bit mode
|
||||
*/
|
||||
_displayfunction = HD44780_8BITMODE;
|
||||
return ( status );
|
||||
}
|
||||
|
||||
//
|
||||
// iowrite(type, value) - send either a command or data byte to lcd
|
||||
// returns zero on success, non zero on failure
|
||||
int iowrite(hd44780::iotype type, uint8_t value)
|
||||
{
|
||||
uint8_t ctlbyte;
|
||||
|
||||
/*
|
||||
* No need to look for 4 bit commands as all bits are already in
|
||||
* proper upper nibble and unsued bits are zero.
|
||||
* This allows the special 4 bit commands to be sent "As is" when
|
||||
* using an 8 bit interface - which is what this i2c LCD uses.
|
||||
*/
|
||||
|
||||
if(type == hd44780::HD44780_IOdata)
|
||||
{
|
||||
ctlbyte = I2Clcd_RS; // control byte with RS and no continue
|
||||
}
|
||||
else
|
||||
{
|
||||
ctlbyte = 0; // control byte with no RS and no continue
|
||||
}
|
||||
|
||||
/*
|
||||
* ensure that previous LCD instruction finished.
|
||||
* There is a 25us offset since there will be at least 1 byte
|
||||
* (the i2c address) transmitted over i2c before the next LCD instruction
|
||||
* information could get to the LCD.
|
||||
* At 400Khz (max rate supported by the LCD) 8 bits plus start and stop
|
||||
* bits is 25us.
|
||||
* So there is at least 25us of time overhead in the physical interface.
|
||||
*/
|
||||
|
||||
waitReady(-25);
|
||||
|
||||
/*
|
||||
* Send the next LCD instruction
|
||||
*/
|
||||
|
||||
Wire.beginTransmission(_Addr);
|
||||
Wire.write(ctlbyte); // send control byte
|
||||
Wire.write(value); // send data/cmd
|
||||
|
||||
if(Wire.endTransmission())
|
||||
return(hd44780::RV_EIO);
|
||||
else
|
||||
return(hd44780::RV_ENOERR);
|
||||
}
|
||||
|
||||
// ================================
|
||||
// === internal class functions ===
|
||||
// ================================
|
||||
// LocateDevice() - Locate I2C LCD device
|
||||
uint8_t LocateDevice()
|
||||
{
|
||||
uint8_t error, address;
|
||||
|
||||
// Search for 6 addresses
|
||||
for(address = 0x3a; address <= 0x3f; address++ )
|
||||
{
|
||||
Wire.beginTransmission(address);
|
||||
error = Wire.endTransmission();
|
||||
|
||||
// chipkit i2c screws up if you do a beginTransmission() too quickly
|
||||
// after an endTransmission()
|
||||
// below 20us will cause it to fail,
|
||||
// we use delay(1) here to accomdate that as well as ensure that
|
||||
// systems with watchdog timers like ESP8266 won't have issues.
|
||||
delay(1);
|
||||
|
||||
if(error == 0) // if no error we found something
|
||||
{
|
||||
return(address);
|
||||
}
|
||||
}
|
||||
return(0); // could not locate device address
|
||||
}
|
||||
|
||||
|
||||
}; // end of class definition
|
||||
#endif
|
||||
Reference in New Issue
Block a user