// vi:ts=4
// ----------------------------------------------------------------------------
// ReadWrite - simple demonstration reading data from LCD
// Created by Bill Perry 2016-08-19
// [email protected]
//
// This example code is unlicensed and is released into the public domain
// ----------------------------------------------------------------------------
//
// This sketch is for LCDs that are directly controlled with Arduino pins.
//
// The purpose of the sketch is demonstrate the ability to read data from
// the LCD. As such, it requires an extra Arduino pin to control the R/W LCD
// pin. See below for configuring the Arduino pins used.
//
// Sketch will print the amount of time since the Arduino has been reset
// on the top row and then read the data from the LCD to print it on the
// second row
//
// If there are errors and the arduino supports a built in LED,
// an error status code will blink on the built in LED.
// Error codes:
// (1) lcd device initalization failed
// (2) lcd device does not support reads
// (3) error reading data from lcd device
// (4) error writing data to lcd device
// (5) read data mismatch
//
#include <hd44780.h>
#include <hd44780ioClass/hd44780_pinIO.h> // Arduino pin i/o class header
// declare Arduino pins used for LCD functions
// and the lcd object
// Note: this can be with or without backlight control:
// without backlight control:
// note that ESP8266 based arduinos must use the Dn defines rather than
// raw pin numbers.
#if defined (ARDUINO_ARCH_ESP8266)
const int rs=D8, rw=A0, en=D9, db4=D4, db5=D5, db6=D6, db7=D7; // esp8266 Lolin/Wemos D1 R1 (uno form factor)
#elif defined(ARDUINO_ARCH_ESP32)
// note: GPIO12 needs a pulldown resistor
const int rs=12, rw=A0, en=13, db4=17, db5=16, db6=27, db7=14; // esp32 espduino32 D1 R32 (uno form factor)
#else
const int rs=8, rw=A0, en=9, db4=4, db5=5, db6=6, db7=7; // for all other devices
#endif
hd44780_pinIO lcd(rs, rw, en, db4, db5, db6, db7);
//with backlight control:
// backlight control requires two additional parameters
// - an additional pin to control the backlight
// - backlight active level which tells the library the level
// needed to turn on the backlight.
// note: If the backlight control pin supports PWM, dimming can be done
// using setBacklight(dimvalue);
//
// WARNING: some lcd keypads have a broken backlight circuit
// If you have a lcd keypad, it is recommended that you first run the
// LCDKeypadCheck sketch to verify that the backlight circuitry
// is ok before enabling backlight control.
// However, the hd44780_PinIO class will autodetect the issue and
// work around it in s/w. If the backlight circuitry is broken,
// dimming will not be possible even if the backlight pin supports PWM.
//
#if defined (ARDUINO_ARCH_ESP8266)
// esp8266 Lolin/Wemos D1 R1 (uno form factor)
//const int rs=D8, rw=A0, en=D9, db4=D4, db5=D5, db6=D6, db7=D7, bl=D10, blLevel=HIGH;
#elif defined(ARDUINO_ARCH_ESP32)
// esp32 espduino32 D1 R32 (uno form factor)
// note: GPIO12 needs a pulldown resistor
// Dimming will not work on esp32 as it does not have analogWrite()
//const int rs=12, rw=A0, en=13, db4=17, db5=16, db6=27, db7=14, bl=5, blLevel=HIGH;
#else
//const int rs=8, rw=A0, en=9, db4=4, db5=5, db6=6, db7=7, bl=10, blLevel=HIGH;
#endif
//hd44780_pinIO lcd(rs, rw, en, db4, db5, db6, db7, bl, blLevel);
// LCD geometry
const int LCD_ROWS = 2;
const int LCD_COLS = 16;
void setup()
{
// initialize LCD with number of columns and rows:
if( lcd.begin(LCD_COLS, LCD_ROWS))
{
// begin() failed so blink the onboard LED if possible
fatalError(1);
}
// check to see if device can read by attempting to read
// the lcd status register. If it fails then assume it was
// because the lcd device does not support reads.
if(lcd.status() < 0)
{
lcd.print("No Read Support");
fatalError(2);
}
}
void loop()
{
static unsigned long lastsecs = -1; // pre-initialize with non zero value
unsigned long secs;
secs = millis() / 1000;
// see if 1 second has passed
// so the display is only updated once per second
if(secs != lastsecs)
{
lastsecs = secs; // keep track of last seconds
// set the cursor position to top line: column 0, row 0
lcd.setCursor(0, 0);
// print uptime on lcd device: (time since last reset)
PrintUpTime(lcd, secs);
// Now copy the characters from the top line to the 2nd line
// This is done character by character by:
// - setting the character position to read
// - reading a character
// - setting the character position to write
// - writing the charcter read
for(int col = 0; col < LCD_COLS; col++)
{
int c;
lcd.setCursor(col, 0);
if((c = lcd.read()) < 0) // if a read error, bomb out
{
lcd.clear();
lcd.print("read fail");
fatalError(3);
}
// check for ':' characters in col 2 and 5
// if not there, consider it a fatal read error
if((col == 2 || col == 5) && c != ':')
{
lcd.clear();
lcd.print("read fail");
fatalError(5);
}
lcd.setCursor(col, 1);
if(lcd.write((uint8_t) c) != 1)
{
lcd.clear();
lcd.print("write fail");
fatalError(4);
}
}
}
}
// PrintUpTime(outdev, secs) - print uptime in HH:MM:SS format
// outdev - the device to send output
// secs - the total number of seconds uptime
void PrintUpTime(Print &outdev, unsigned long secs)
{
unsigned int hr, mins, sec;
// convert total seconds to hours, mins, seconds
mins = secs / 60; // how many total minutes
hr = mins / 60; // how many total hours
mins = mins % 60; // how many minutes within the hour
sec = secs % 60; // how many seconds within the minute
// print uptime in HH:MM:SS format
// Print class does not support fixed width formatting
// so insert a zero if number smaller than 10
if(hr < 10)
outdev.write('0');
outdev.print((int)hr);
outdev.write(':');
if(mins < 10)
outdev.write('0');
outdev.print((int)mins);
outdev.write(':');
if(sec < 10)
outdev.write('0');
outdev.print((int)sec);
}
// fatalError() - loop & blink and error code
void fatalError(int ecode)
{
hd44780::fatalError(ecode); // does not return
}