diff --git a/.arduino-ci.yml b/.arduino-ci.yml
new file mode 100644
index 0000000..77a333f
--- /dev/null
+++ b/.arduino-ci.yml
@@ -0,0 +1,28 @@
+platforms:
+  rpipico:
+    board: rp2040:rp2040:rpipico
+    package: rp2040:rp2040
+    gcc:
+      features:
+      defines:
+        - ARDUINO_ARCH_RP2040
+      warnings:
+      flags:
+
+packages:
+  rp2040:rp2040:
+    url: https://github.com/earlephilhower/arduino-pico/releases/download/global/package_rp2040_index.json
+
+compile:
+  # Choosing to run compilation tests on 2 different Arduino platforms
+  platforms:
+    - uno
+    # - due
+    # - zero
+    # - leonardo
+    - m4
+    - esp32
+    - esp8266
+    # - mega2560
+    - rpipico
+
diff --git a/.github/FUNDING.yml b/.github/FUNDING.yml
new file mode 100644
index 0000000..90d9ab4
--- /dev/null
+++ b/.github/FUNDING.yml
@@ -0,0 +1,4 @@
+# These are supported funding model platforms
+
+github: RobTillaart
+
diff --git a/.github/workflows/arduino-lint.yml b/.github/workflows/arduino-lint.yml
new file mode 100644
index 0000000..8a26f14
--- /dev/null
+++ b/.github/workflows/arduino-lint.yml
@@ -0,0 +1,13 @@
+
+name: Arduino-lint
+
+on: [push, pull_request]
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: arduino/arduino-lint-action@v1
+        with:
+          library-manager: update
+          compliance: strict
diff --git a/.github/workflows/arduino_test_runner.yml b/.github/workflows/arduino_test_runner.yml
new file mode 100644
index 0000000..fadfa90
--- /dev/null
+++ b/.github/workflows/arduino_test_runner.yml
@@ -0,0 +1,17 @@
+---
+name: Arduino CI
+
+on: [push, pull_request]
+
+jobs:
+  runTest:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: 2.6
+      - run: |
+          gem install arduino_ci
+          arduino_ci.rb
diff --git a/.github/workflows/jsoncheck.yml b/.github/workflows/jsoncheck.yml
new file mode 100644
index 0000000..37a1129
--- /dev/null
+++ b/.github/workflows/jsoncheck.yml
@@ -0,0 +1,18 @@
+name: JSON check
+
+on:
+  push:
+    paths:
+      - '**.json'
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: json-syntax-check
+        uses: limitusus/json-syntax-check@v1
+        with:
+          pattern: "\\.json$"
+
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..5add16e
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,11 @@
+# Change Log HC4051
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/)
+and this project adheres to [Semantic Versioning](http://semver.org/).
+
+
+## [0.1.0] - 2023-01-25
+- initial version
+
diff --git a/HC4051.h b/HC4051.h
new file mode 100644
index 0000000..1128070
--- /dev/null
+++ b/HC4051.h
@@ -0,0 +1,96 @@
+#pragma once
+//
+//    FILE: HC4051.h
+//  AUTHOR: Rob Tillaart
+//    DATE: 2023-01-25
+// VERSION: 0.1.0
+// PURPOSE: Arduino library for CD74HC4051 8 channel multiplexer and compatibles.
+//     URL: https://github.com/RobTillaart/HC4051
+
+
+
+#include "Arduino.h"
+
+#define HC4051_LIB_VERSION         (F("0.1.0"))
+
+
+class HC4051
+{
+public:
+  explicit HC4051(uint8_t A, uint8_t B, uint8_t C, uint8_t enablePin = 255)
+  {
+    _pins[0] = A;
+    _pins[1] = B;
+    _pins[2] = C;
+    uint8_t i = 3;
+    while (i--)
+    {
+      pinMode(_pins[i], OUTPUT);
+      digitalWrite(_pins[i], LOW);
+    }
+    _channel = 0;
+
+    if (enablePin != 255)
+    {
+      _enablePin = enablePin;
+      pinMode(_enablePin, OUTPUT);
+      digitalWrite(_enablePin, HIGH);
+    }
+  }
+
+
+  void setChannel(uint8_t channel)
+  {
+    if ((channel & 0x07) != _channel)
+    {
+      _channel = channel & 0x07;
+      digitalWrite(_pins[0], _channel & 0x01);
+      digitalWrite(_pins[1], _channel & 0x02);
+      digitalWrite(_pins[2], _channel & 0x04);
+    }
+  }
+
+
+  uint8_t getChannel()
+  {
+    return _channel;
+  }
+
+
+  void enable()
+  {
+    if (_enablePin != 255)
+    {
+      digitalWrite(_enablePin, LOW);
+    }
+  }
+
+
+  void disable()
+  {
+    if (_enablePin != 255)
+    {
+      digitalWrite(_enablePin, HIGH);
+    }
+  }
+
+
+  bool isEnabled()
+  {
+    if (_enablePin != 255)
+    {
+      return (digitalRead(_enablePin) == LOW);
+    }
+    return true;
+  }
+
+
+private:
+  uint8_t  _pins[3];
+  uint8_t  _enablePin = 255;
+  uint8_t  _channel   = 0;
+};
+
+
+//  -- END OF FILE --
+
diff --git a/LICENSE b/LICENSE
index 9833ff9..16ef155 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2023 Rob Tillaart
+Copyright (c) 2023-2023 Rob Tillaart
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/README.md b/README.md
index c3e6aaa..d23bcf3 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,98 @@
+
+[![Arduino CI](https://github.com/RobTillaart/HC4051/workflows/Arduino%20CI/badge.svg)](https://github.com/marketplace/actions/arduino_ci)
+[![Arduino-lint](https://github.com/RobTillaart/HC4051/actions/workflows/arduino-lint.yml/badge.svg)](https://github.com/RobTillaart/HC4051/actions/workflows/arduino-lint.yml)
+[![JSON check](https://github.com/RobTillaart/HC4051/actions/workflows/jsoncheck.yml/badge.svg)](https://github.com/RobTillaart/HC4051/actions/workflows/jsoncheck.yml)
+[![License: MIT](https://img.shields.io/badge/license-MIT-green.svg)](https://github.com/RobTillaart/HC4051/blob/master/LICENSE)
+[![GitHub release](https://img.shields.io/github/release/RobTillaart/HC4051.svg?maxAge=3600)](https://github.com/RobTillaart/HC4051/releases)
+
+
 # HC4051
-Arduino library for CD74HC4051 1x8 channel multiplexer and compatibles.
+
+HC4051 is an Arduino library for a HC4051 1x8 channel multiplexer.
+
+
+## Description
+
+HC4051 is a library to control the CD74HC4051 8 channel
+multiplexer / demultiplexer and compatible devices.
+
+The HC4051 allows e.g one analog port read up to 8 different analog channels,
+or one digital port to read the state of 8 buttons.
+
+
+The channel selection is done with four select lines **A, B, C**
+
+The device can be enabled/disabled by the enable line **INH**
+
+
+#### Compatibles
+
+to elaborate.
+
+
+#### Related to 
+
+- https://github.com/RobTillaart/HC4051  (1x8 mux)
+- https://github.com/RobTillaart/HC4052  (2x8 mux)
+- https://github.com/RobTillaart/HC4053  (3x2 mux)
+- https://github.com/RobTillaart/HC4067  (1x16 mux)
+
+
+## Hardware connection
+
+Typical connection is to connect the four **select pins** to four IO Pins of your board.
+
+The optional **enablePin (INH)** must be connected to GND if not used.
+This way the device is continuous enabled.
+
+Example multiplexing analog in.
+
+```
+        processor                      HC4051
+     +-------------+              +-------------+
+     |             |              |             |
+     |           A |------------->| S0       Y0 |
+     |           B |------------->| S1       Y1 |
+     |           C |------------->| S2       Y2 |
+     |             |              |          Y3 |
+     |          E  |------------->| INH      Y4 |
+     |             |              |          Y5 |
+     |         A0  |<-------------| Y        Y6 |
+     |             |              |          Y7 |
+     |         GND |--------------| GND      Y8 |
+     |             |              | VCC         |
+     |             |              |             |
+     +-------------+              +-------------+
+```
+
+
+## Interface
+
+```cpp
+#include "HC4051.h"
+```
+
+#### Core
+
+- **HC4051(uint8_t A, uint8_t B, uint8_t C, uint8_t enablePin = 255)** constructor.
+Set the three select pins and optional the enable pin.
+If the enablePin == 255 it is considered not used.
+- **void setChannel(uint8_t channel)** set the current channel.
+Valid values 0..7, this value is not checked, only the lower 3 bits will be used.
+- **uint8_t getChannel()** get current channel 0..7.
+
+
+#### Enable
+
+These functions work only if enablePin is set in the constructor.
+
+- **void enable()** idem.
+- **void disable()** idem.
+- **bool isEnabled()** idem.
+Also returns true if enablePin is not set.
+
+
+## Future
+
+- keep in sync with HC4067 et.al.
+
diff --git a/examples/HC4051_demo/HC4051_demo.ino b/examples/HC4051_demo/HC4051_demo.ino
new file mode 100644
index 0000000..2fe05f6
--- /dev/null
+++ b/examples/HC4051_demo/HC4051_demo.ino
@@ -0,0 +1,36 @@
+//
+//    FILE: HC4051_demo.ino
+//  AUTHOR: Rob Tillaart
+// PURPOSE: Demo for HC4051 8 channel (simple) multiplexer
+
+
+#include "HC4051.h"
+
+HC4051 mp(4, 5, 6);
+
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println(__FILE__);
+  Serial.print("HC4051 LIBRARY VERSION: ");
+  Serial.println(HC4051_LIB_VERSION);
+  Serial.println();
+
+  delay(1000);
+}
+
+
+void loop()
+{
+  for (uint8_t channel = 0; channel < 8; channel++)
+  {
+    mp.setChannel(channel);
+    Serial.println(analogRead(A0));
+    delay(100);
+  }
+  Serial.println();
+}
+
+
+//  -- END OF FILE --
diff --git a/keywords.txt b/keywords.txt
new file mode 100644
index 0000000..875e5c7
--- /dev/null
+++ b/keywords.txt
@@ -0,0 +1,17 @@
+# Syntax Colouring Map For HC4051
+
+# Data types (KEYWORD1)
+HC4051	KEYWORD1
+
+# Methods and Functions (KEYWORD2)
+setChannel	KEYWORD2
+getChannel	KEYWORD2
+enable	KEYWORD2
+disable	KEYWORD2
+isEnabled	KEYWORD2
+
+
+# Constants (LITERAL1)
+HC4051_LIB_VERSION	LITERAL1
+
+
diff --git a/library.json b/library.json
new file mode 100644
index 0000000..310dff3
--- /dev/null
+++ b/library.json
@@ -0,0 +1,23 @@
+{
+  "name": "HC4051",
+  "keywords": "",
+  "description": "Arduino library for a HC4051 1x8 channel multiplexer.",
+  "authors":
+  [
+    {
+      "name": "Rob Tillaart",
+      "email": "Rob.Tillaart@gmail.com",
+      "maintainer": true
+    }
+  ],
+  "repository":
+  {
+    "type": "git",
+    "url": "https://github.com/RobTillaart/HC4051.git"
+  },
+  "version": "0.1.0",
+  "license": "MIT",
+  "frameworks": "arduino",
+  "platforms": "*",
+  "headers": "HC4051.h"
+}
diff --git a/library.properties b/library.properties
new file mode 100644
index 0000000..a42fc54
--- /dev/null
+++ b/library.properties
@@ -0,0 +1,11 @@
+name=HC4051
+version=0.1.0
+author=Rob Tillaart <rob.tillaart@gmail.com>
+maintainer=Rob Tillaart <rob.tillaart@gmail.com>
+sentence=Arduino library for a HC4051 1x8 channel multiplexer
+paragraph=
+category=Sensors
+url=https://github.com/RobTillaart/HC4051
+architectures=*
+includes=HC4051.h
+depends=
diff --git a/test/unit_test_001.cpp b/test/unit_test_001.cpp
new file mode 100644
index 0000000..78af02e
--- /dev/null
+++ b/test/unit_test_001.cpp
@@ -0,0 +1,70 @@
+//
+//    FILE: unit_test_001.cpp
+//  AUTHOR: Rob Tillaart
+//    DATE: 2023-01-25
+// PURPOSE: unit tests for the HC4051 sensor
+//          https://github.com/RobTillaart/HC4067
+//
+
+// supported assertions
+// ----------------------------
+// assertEqual(expected, actual)
+// assertNotEqual(expected, actual)
+// assertLess(expected, actual)
+// assertMore(expected, actual)
+// assertLessOrEqual(expected, actual)
+// assertMoreOrEqual(expected, actual)
+// assertTrue(actual)
+// assertFalse(actual)
+// assertNull(actual)
+
+
+#include <ArduinoUnitTests.h>
+
+#include "Arduino.h"
+#include "HC4051.h"
+
+
+unittest_setup()
+{
+    fprintf(stderr, "HC4051_LIB_VERSION: %s\n", (char *) HC4051_LIB_VERSION);
+}
+
+
+unittest_teardown()
+{
+}
+
+
+unittest(test_channel)
+{
+  HC4051 mp(3,4,5);
+
+  for (int ch = 0; ch < 8; ch++)
+  {
+    mp.setChannel(ch);
+    assertEqual(ch, mp.getChannel());
+  }
+}
+
+
+unittest(test_enable)
+{
+  HC4051 mp1(3,4,5);
+  assertTrue(mp1.isEnabled());
+
+  HC4051 mp2(3,4,5,6);
+  assertFalse(mp2.isEnabled());
+
+  mp2.enable();
+  assertTrue(mp2.isEnabled());
+
+  mp2.disable();
+  assertFalse(mp2.isEnabled());
+}
+
+
+unittest_main()
+
+
+//  -- END OF FILE --