.github/workflows/arduino-checks.yml

@@ -0,0 +1,98 @@
+# This is a basic workflow to help you get started with Actions for Arduino library projects
+
+name: Arduino Library Checks
+
+# Controls when the action will run.
+on:
+  # Triggers the workflow on push or pull request events but only for the develop branch
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+jobs:
+
+  # This defines a job for checking the Arduino library format specifications
+  # see <https://github.com/marketplace/actions/arduino-arduino-lint-action>
+
+  lint:
+    name: check library format
+    runs-on: ubuntu-latest
+    continue-on-error: true
+
+    steps:
+      - uses: actions/checkout@v2
+
+      # Arduino - lint
+      - name: Arduino-lint
+        uses: arduino/arduino-lint-action@v1
+        with:
+          library-manager: update
+          verbose: false
+
+  # These jobs are used to compile the examples fot the specific processor/board.
+  # see <https://github.com/marketplace/actions/compile-arduino-sketches>
+
+  compile-uno:
+    name: compile uno examples
+    runs-on: ubuntu-latest
+    continue-on-error: true
+
+    steps:
+      - uses: actions/checkout@v2
+
+      # Compile Examples for UNO
+      - name: Compile examples for UNO
+        uses: arduino/compile-sketches@v1
+        with:
+          verbose: true
+          fqbn: arduino:avr:uno
+          sketch-paths: |
+            - 'examples/LiquidCrystal_PCF8574_Test'
+
+  compile-esp8266:
+    name: compile esp8266 examples
+    runs-on: ubuntu-latest
+    continue-on-error: true
+
+    steps:
+      - uses: actions/checkout@v2
+
+      # Compile Examples for ESP8266
+      - name: Compile examples for ESP8266
+        uses: arduino/compile-sketches@v1
+        with:
+          verbose: true
+          platforms: |
+            # Install ESP8266 platform via Boards Manager
+            - name: esp8266:esp8266
+              source-url: https://arduino.esp8266.com/stable/package_esp8266com_index.json
+              version: 3.0.0
+          fqbn: esp8266:esp8266:nodemcuv2
+          sketch-paths: |
+            - 'examples/LiquidCrystal_PCF8574_Test'
+
+  compile-esp32:
+    name: compile ESP32 examples
+    runs-on: ubuntu-latest
+    continue-on-error: true
+
+    steps:
+      - uses: actions/checkout@v2
+
+      # Compile Examples for ESP32
+      - name: Compile examples for ESP32
+        uses: arduino/compile-sketches@v1
+        with:
+          verbose: true
+            # Install ESP32 platform via Boards Manager
+          platforms: |
+            - name: "esp32:esp32"
+              source-url: https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
+              version: 2.0.3
+          fqbn: esp32:esp32:esp32
+          sketch-paths: |
+            - 'examples/LiquidCrystal_PCF8574_Test'

LICENSE

@@ -1,15 +1,30 @@
-Software License Agreement (BSD License)
+BSD 3-Clause License
 
-Copyright (c) 2005-2016 by Matthias Hertel,  http://www.mathertel.de/
+Copyright (c) 2005-2020, Matthias Hertel,  http://www.mathertel.de/
 
 All rights reserved.
 
-Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
 
-•Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 
-•Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 
-•Neither the name of the copyright owners nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. 
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
 
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
 
-See http://www.mathertel.de/License.aspx
+3. Neither the name of the copyright holder nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

README.md

@@ -1,10 +1,50 @@
 # Arduino Library for LiquidCrystal displays with I2C PCF8574 adapter
 
+[![Arduino Library Checks](https://github.com/mathertel/LiquidCrystal_PCF8574/actions/workflows/arduino-checks.yml/badge.svg)](https://github.com/mathertel/LiquidCrystal_PCF8574/actions/workflows/arduino-checks.yml)
+
+[![arduino-library-badge](https://www.ardu-badge.com/badge/LiquidCrystal_PCF8574.svg?)](https://www.ardu-badge.com/LiquidCrystal_PCF8574)
+
 A library for driving LiquidCrystal displays (LCD) by using the I2C bus and an PCF8574 I2C adapter.
 
-There are modules that can be soldered or stacked to the display that offers a I2C interface for communication instead of the 8+ digital lines that are used to send data to the display.
+There are modules that can be soldered or stacked to the display that offers an I2C interface for communication instead of the 8+ digital lines that are used to send data to the display.
 
-Most of these modules used the internal wiring that is supported by this library. If you use a module with a different wiring you can adjust this in the code (see comments). 
+Most of these modules use the wiring that is supported by this library's default configuration.
+If you use a module with a different wiring, you can use one of the class constructors which allow you to specify the pin assignments.
 
 See the web site for more details and pictures: <https://www.mathertel.de/Arduino/LiquidCrystal_PCF8574.aspx>
 
+## Changes Version 2.2.0 (2023-04-03)
+
+The default i2c address 0x27 is set as default parameter.
+
+You can use an explicit i2c address with
+
+``` cpp
+LiquidCrystal_PCF8574 lcd(0x22);  // set the LCD address to 0x22
+```
+
+or you can rely on the default i2c address = 0x27 with
+
+``` cpp
+LiquidCrystal_PCF8574 lcd();  // use the default LCD address == 0x27
+```
+
+See datasheet of PCF8574 (and PCF8574A) for further info on usable i2c addresses.
+
+Thanks for contribution from @robaol
+
+## Changes Version 2.1.0 (2022-08-21)
+
+Enables using a non-default i2c / TwoWire port for boards that support multiple ports.
+
+Added example `LCD_Burnin.ino` showing how to transfer a 20 char and 4 lines buffer to a device all at once.
+
+Thanks for additions from @uutzinger
+
+## Changes Version 2.0.0 (2022-05-26)
+
+* The interface was modified to use 8-bit datatypes as supported by the underling hardware.
+* A createChar version with PROGMEM character data for AVR processors was added.
+* A constructor with pin assignments was added to allow easy adoption to other wirings than the default.
+
+Thanks for additions from @markisch.

examples/LCD_Burnin/LCD_Burnin.ino

@@ -0,0 +1,51 @@
+// LCD with i2c backpack test
+// This example shows how to transfer an in-memory buffer to the LCD at once.
+// A TwoWire instance is given as a parameter to lcd.begin to show how to pass a non default wire interface.
+// Urs Utzinger, 2020
+
+#include <Arduino.h>
+#include <Wire.h>
+#include "LiquidCrystal_PCF8574.h"
+
+TwoWire Wire_1 = TwoWire();
+
+LiquidCrystal_PCF8574 lcd(0x27);  // set the LCD address to 0x27 
+char lcdDisplay[4][20];           // 4 lines of 20 character buffer
+
+void setup()
+{
+  Wire_1.begin(D1, D2);  // custom i2c port on ESP
+  Wire_1.setClock(100000); // standard 100kHz speed
+  Wire_1.setClockStretchLimit(200000); // some devices might need clock stretching
+  lcd.begin(20,4, Wire_1);
+  lcd.setBacklight(255);
+}
+
+void loop()
+{
+  char lcdbuf[21];
+  const char someLine[] = "0123456789ABCDEF1234";  // 20 chars
+
+  // fill the screen buffer
+  strncpy(&lcdDisplay[0][0], someLine , 20);
+  strncpy(&lcdDisplay[1][0], someLine , 20);
+  strncpy(&lcdDisplay[2][0], someLine , 20);
+  strncpy(&lcdDisplay[3][0], someLine , 20);
+  // prepare screen
+  lcd.home();
+  lcd.clear();
+  lcd.setCursor(0, 0);   
+  // copy the buffer to the screen
+  // 1st line continues at 3d line
+  // 2nd line continues at 4th line
+  strncpy(lcdbuf, &lcdDisplay[0][0], 20); lcdbuf[20] = '\0'; // create a termineted text line 
+  lcd.print(lcdbuf);                                         // print the line to screen
+  strncpy(lcdbuf, &lcdDisplay[2][0], 20); lcdbuf[20] = '\0';
+  lcd.print(lcdbuf); 
+  strncpy(lcdbuf, &lcdDisplay[1][0], 20); lcdbuf[20] = '\0';
+  lcd.print(lcdbuf); 
+  strncpy(lcdbuf, &lcdDisplay[3][0], 20); lcdbuf[20] = '\0';
+  lcd.print(lcdbuf);
+
+  delay(50); // keep short to test if screen corrupts with frequent writes
+}

examples/LiquidCrystal_PCF8574_Test/LiquidCrystal_PCF8574_Test.ino

@@ -1,12 +1,21 @@
-#include <LiquidCrystal_PCF8574.h>
+// This example shows various featues of the library for LCD with 16 chars and 2 lines.
+
+#include <Arduino.h>
 #include <Wire.h>
+#include <LiquidCrystal_PCF8574.h>
 
-LiquidCrystal_PCF8574 lcd(0x27); // set the LCD address to 0x27 for a 16 chars and 2 line display
+LiquidCrystal_PCF8574 lcd(0x27);  // set the LCD address to 0x27 for a 16 chars and 2 line display
 
 int show = -1;
 
-void setup()
-{
+// 2 custom characters
+
+byte dotOff[] = { 0b00000, 0b01110, 0b10001, 0b10001,
+                  0b10001, 0b01110, 0b00000, 0b00000 };
+byte dotOn[] = { 0b00000, 0b01110, 0b11111, 0b11111,
+                 0b11111, 0b01110, 0b00000, 0b00000 };
+
+void setup() {
   int error;
 
   Serial.begin(115200);
@@ -16,7 +25,7 @@ void setup()
   while (!Serial)
     ;
 
-  Serial.println("Dose: check for LCD");
+  Serial.println("Probing for PCF8574 on address 0x27...");
 
   // See http://playground.arduino.cc/Main/I2cScanner how to test for a I2C device.
   Wire.begin();
@@ -28,17 +37,19 @@ void setup()
   if (error == 0) {
     Serial.println(": LCD found.");
     show = 0;
-    lcd.begin(16, 2); // initialize the lcd
+    lcd.begin(16, 2);  // initialize the lcd
+
+    lcd.createChar(1, dotOff);
+    lcd.createChar(2, dotOn);
 
   } else {
     Serial.println(": LCD not found.");
-  } // if
+  }  // if
 
-} // setup()
+}  // setup()
 
 
-void loop()
-{
+void loop() {
   if (show == 0) {
     lcd.setBacklight(255);
     lcd.home();
@@ -96,10 +107,16 @@ void loop()
     lcd.clear();
     lcd.print("write-");
 
-  } else if (show > 12) {
+  } else if (show == 13) {
+    lcd.clear();
+    lcd.print("custom 1:<\01>");
+    lcd.setCursor(0, 1);
+    lcd.print("custom 2:<\02>");
+
+  } else {
     lcd.print(show - 13);
-  } // if
+  }  // if
 
   delay(1400);
   show = (show + 1) % 16;
-} // loop()
+}  // loop()

keywords.txt

@@ -6,7 +6,7 @@
 # Datatypes (KEYWORD1)
 #######################################
 
-LiquidCrystal_PCF8574 KEYWORD1
+LiquidCrystal_PCF8574	KEYWORD1
 
 #######################################
 # Methods and Functions (KEYWORD2)
@@ -29,8 +29,10 @@ autoscroll	KEYWORD2
 noAutoscroll	KEYWORD2
 setBacklight	KEYWORD2
 createChar	KEYWORD2
+createChar_P	KEYWORD2
 setCursor	KEYWORD2
 write	KEYWORD2
+command	KEYWORD2
 
 #######################################
 # Instances (KEYWORD2)

library.properties

@@ -1,9 +1,9 @@
 name=LiquidCrystal_PCF8574
-version=1.2.0
+version=2.2.0
 author=Matthias Hertel
 maintainer=Matthias Hertel <www.mathertel.de>
 sentence=A library for driving LiquidCrystal displays (LCD) by using the I2C bus and an PCF8574 I2C adapter.
 paragraph=This library uses the original Wire library for communication.
-category=Communication
+category=Display
 url=https://www.mathertel.de/Arduino/LiquidCrystal_PCF8574.aspx
 architectures=*