diff --git a/lib/PCA95x5/LICENSE b/lib/PCA95x5/LICENSE
new file mode 100644
index 0000000..f6f330a
--- /dev/null
+++ b/lib/PCA95x5/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022 Hideaki Tai
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/lib/PCA95x5/PCA95x5.h b/lib/PCA95x5/PCA95x5.h
new file mode 100644
index 0000000..a82d73a
--- /dev/null
+++ b/lib/PCA95x5/PCA95x5.h
@@ -0,0 +1,187 @@
+/*
+ * @Description: None
+ * @version: V1.0.0
+ * @Author: None
+ * @Date: 2023-07-14 09:26:36
+ * @LastEditors: LILYGO_L
+ * @LastEditTime: 2023-07-14 09:45:19
+ * @License: GPL 3.0
+ */
+#include <Arduino.h>
+#include <Wire.h>
+
+namespace PCA95x5 {
+
+namespace Reg {
+    enum : uint8_t {
+        INPUT_PORT_0,
+        INPUT_PORT_1,
+        OUTPUT_PORT_0,
+        OUTPUT_PORT_1,
+        POLARITY_INVERSION_PORT_0,
+        POLARITY_INVERSION_PORT_1,
+        CONFIGURATION_PORT_0,
+        CONFIGURATION_PORT_1,
+    };
+}
+
+namespace Port {
+    enum Port : uint8_t {
+        P00,
+        P01,
+        P02,
+        P03,
+        P04,
+        P05,
+        P06,
+        P07,
+        P10,
+        P11,
+        P12,
+        P13,
+        P14,
+        P15,
+        P16,
+        P17,
+    };
+}  // namespace Port
+
+namespace Level {
+    enum Level : uint8_t { L, H };
+    enum LevelAll : uint16_t { L_ALL = 0x0000, H_ALL = 0xFFFF };
+}  // namespace Level
+
+namespace Polarity {
+    enum Polarity : uint8_t { ORIGINAL, INVERTED };
+    enum PolarityAll : uint16_t { ORIGINAL_ALL = 0x0000, INVERTED_ALL = 0xFFFF };
+}  // namespace Polarity
+
+namespace Direction {
+    enum Direction : uint8_t { OUT, IN };
+    enum DirectionAll : uint16_t { OUT_ALL = 0x0000, IN_ALL = 0xFFFF };
+}  // namespace Direction
+
+template <typename WireType = TwoWire>
+class PCA95x5 {
+    union Ports {
+        uint16_t w;
+        uint8_t b[2];
+    };
+
+    static constexpr uint8_t BASE_I2C_ADDR = 0x20;
+
+    WireType* wire {nullptr};
+    uint8_t addr {BASE_I2C_ADDR};
+    Ports input {0x0000};
+    Ports output {0xFFFF};
+    Ports pol {0x0000};
+    Ports dir {0xFFFF};
+    uint8_t status {0x00};
+
+public:
+    void attach(WireType& wire, uint8_t i2c_addr = BASE_I2C_ADDR) {
+        this->wire = &wire;
+        this->addr = i2c_addr;
+    }
+
+    uint16_t read() {
+        read_bytes(this->addr, Reg::INPUT_PORT_0, this->input.b, 2);
+        return this->input.w;
+    }
+    Level::Level read(const Port::Port port) {
+        uint16_t v = read();
+        return (v & (1 << port)) ? Level::H : Level::L;
+    }
+    Level::Level read(uint8_t port) {
+    uint16_t v = read();
+    return (v & (1 << port)) ? Level::H : Level::L;
+    }
+
+    bool write(const uint16_t value) {
+        this->output.w = value;
+        return write_impl();
+    }
+    bool write(const Port::Port port, const Level::Level level) {
+        if (level == Level::H) {
+            this->output.w |= (1 << port);
+        } else {
+            this->output.w &= ~(1 << port);
+        }
+        return write_impl();
+    }
+    bool write(uint8_t port, uint8_t level) {
+        if (level == Level::H) {
+            this->output.w |= (1 << port);
+        } else {
+            this->output.w &= ~(1 << port);
+        }
+        return write_impl();
+    }
+
+    bool polarity(const uint16_t value) {
+        this->pol.w = value;
+        return polarity_impl();
+    }
+    bool polarity(const Port::Port port, const Polarity::Polarity pol) {
+        if (pol == Polarity::INVERTED) {
+            this->pol.w |= (1 << port);
+        } else {
+            this->pol.w &= ~(1 << port);
+        }
+        return polarity_impl();
+    }
+
+    bool direction(const uint16_t value) {
+        this->dir.w = value;
+        return direction_impl();
+    }
+
+    bool direction(const Port::Port port, const Direction::Direction dir) {
+        if (dir == Direction::IN) {
+            this->dir.w |= (1 << port);
+        } else {
+            this->dir.w &= ~(1 << port);
+        }
+        return direction_impl();
+    }
+
+    uint8_t i2c_error() const {
+        return status;
+    }
+
+private:
+    bool write_impl() {
+        return write_bytes(this->addr, Reg::OUTPUT_PORT_0, this->output.b, 2);
+    }
+
+    bool polarity_impl() {
+        return write_bytes(this->addr, Reg::POLARITY_INVERSION_PORT_0, this->pol.b, 2);
+    }
+
+    bool direction_impl() {
+        return write_bytes(this->addr, Reg::CONFIGURATION_PORT_0, this->dir.b, 2);
+    }
+
+    int8_t read_bytes(const uint8_t dev, const uint8_t reg, uint8_t* data, const uint8_t size) {
+        wire->beginTransmission(dev);
+        wire->write(reg);
+        wire->endTransmission();
+        wire->requestFrom(dev, size);
+        int8_t count = 0;
+        while (wire->available()) data[count++] = wire->read();
+        return count;
+    }
+
+    bool write_bytes(const uint8_t dev, const uint8_t reg, const uint8_t* data, const uint8_t size) {
+        wire->beginTransmission(dev);
+        wire->write(reg);
+        for (uint8_t i = 0; i < size; i++) wire->write(data[i]);
+        status = wire->endTransmission();
+        return (status == 0);
+    }
+};
+
+}  // namespace PCA95x5
+
+using PCA9535 = PCA95x5::PCA95x5<>;
+using PCA9555 = PCA95x5::PCA95x5<>;
diff --git a/lib/PCA95x5/README.md b/lib/PCA95x5/README.md
new file mode 100644
index 0000000..52c4283
--- /dev/null
+++ b/lib/PCA95x5/README.md
@@ -0,0 +1,127 @@
+# PCA95x5
+
+Arduino library for [PCA9535](https://www.ti.com/product/PCA9535) and [PCA9555](https://www.ti.com/product/PCA9555) (Remote 16-bit I2C and SMBus I/O Expander with Interrupt Output and Configuration Registers).
+
+## Usage
+
+You can specify a port using either index (`0` - `15`) or enum (`PCA95x5::Port::P02`, etc.).
+
+### Input
+
+```C++
+#include <PCA95x5.h>
+
+// select one of them
+PCA9535 ioex;
+// PCA9555 ioex;
+
+void setup() {
+    Serial.begin(115200);
+    delay(2000);
+
+    Wire.begin();
+    ioex.attach(Wire);
+    ioex.polarity(PCA95x5::Polarity::ORIGINAL_ALL);
+    ioex.direction(PCA95x5::Direction::IN_ALL);
+}
+
+void loop() {
+    Serial.println(ioex.read(), BIN);
+    delay(1000);
+}
+```
+
+### Output
+
+```C++
+#include <PCA95x5.h>
+
+// select one of them
+// PCA9535 ioex;
+PCA9555 ioex;
+
+void setup() {
+    Serial.begin(115200);
+    delay(2000);
+
+    Wire.begin();
+    ioex.attach(Wire);
+    ioex.polarity(PCA95x5::Polarity::ORIGINAL_ALL);
+    ioex.direction(PCA95x5::Direction::OUT_ALL);
+    ioex.write(PCA95x5::Level::L_ALL);
+}
+
+void loop() {
+    for (size_t i = 0; i < 16; ++i) {
+        Serial.print("set port high: ");
+        Serial.println(i);
+
+        ioex.write(i, PCA95x5::Level::H);
+        Serial.println(ioex.read(), BIN);
+        delay(500);
+    }
+
+    for (size_t i = 0; i < 16; ++i) {
+        Serial.print("set port low: ");
+        Serial.println(i);
+
+        ioex.write(i, PCA95x5::Level::L);
+        Serial.println(ioex.read(), BIN);
+        delay(500);
+    }
+}
+```
+
+## APIs
+
+```C++
+void attach(WireType& wire, uint8_t i2c_addr = BASE_I2C_ADDR);
+uint16_t read();
+Level::Level read(const uint8_t port);
+bool write(const uint16_t value);
+bool write(const uint8_t port, const Level::Level level);
+bool polarity(const uint16_t value);
+bool polarity(const uint8_t port, const Polarity::Polarity pol);
+bool direction(const uint16_t value);
+bool direction(const uint8_t port, const Direction::Direction dir);
+uint8_t i2c_error() const;
+```
+
+```C++
+namespace Port {
+    enum Port : uint8_t {
+        P00,
+        P01,
+        P02,
+        P03,
+        P04,
+        P05,
+        P06,
+        P07,
+        P10,
+        P11,
+        P12,
+        P13,
+        P14,
+        P15,
+        P16,
+        P17,
+    };
+}
+namespace Level {
+    enum Level : uint8_t { L, H };
+    enum LevelAll : uint16_t { L_ALL = 0x0000, H_ALL = 0xFFFF };
+}
+namespace Polarity {
+    enum Polarity : uint8_t { ORIGINAL, INVERTED };
+    enum PolarityAll : uint16_t { ORIGINAL_ALL = 0x0000, INVERTED_ALL = 0xFFFF };
+}
+namespace Direction {
+    enum Direction : uint8_t { OUT, IN };
+    enum DirectionAll : uint16_t { OUT_ALL = 0x0000, IN_ALL = 0xFFFF };
+}
+```
+
+## License
+
+MIT
diff --git a/lib/PCA95x5/examples/input/input.ino b/lib/PCA95x5/examples/input/input.ino
new file mode 100644
index 0000000..e410f5d
--- /dev/null
+++ b/lib/PCA95x5/examples/input/input.ino
@@ -0,0 +1,18 @@
+#include <PCA95x5.h>
+
+PCA9555 ioex;
+
+void setup() {
+    Serial.begin(115200);
+    delay(2000);
+
+    Wire.begin();
+    ioex.attach(Wire);
+    ioex.polarity(PCA95x5::Polarity::ORIGINAL_ALL);
+    ioex.direction(PCA95x5::Direction::IN_ALL);
+}
+
+void loop() {
+    Serial.println(ioex.read(), BIN);
+    delay(1000);
+}
diff --git a/lib/PCA95x5/examples/output/output.ino b/lib/PCA95x5/examples/output/output.ino
new file mode 100644
index 0000000..7f83943
--- /dev/null
+++ b/lib/PCA95x5/examples/output/output.ino
@@ -0,0 +1,34 @@
+#include <PCA95x5.h>
+
+PCA9555 ioex;
+
+void setup() {
+    Serial.begin(115200);
+    delay(2000);
+
+    Wire.begin();
+    ioex.attach(Wire);
+    ioex.polarity(PCA95x5::Polarity::ORIGINAL_ALL);
+    ioex.direction(PCA95x5::Direction::OUT_ALL);
+    ioex.write(PCA95x5::Level::L_ALL);
+}
+
+void loop() {
+    for (size_t i = 0; i < 16; ++i) {
+        Serial.print("set port high: ");
+        Serial.println(i);
+
+        ioex.write(i, PCA95x5::Level::H);
+        Serial.println(ioex.read(), BIN);
+        delay(500);
+    }
+
+    for (size_t i = 0; i < 16; ++i) {
+        Serial.print("set port low: ");
+        Serial.println(i);
+
+        ioex.write(i, PCA95x5::Level::L);
+        Serial.println(ioex.read(), BIN);
+        delay(500);
+    }
+}
diff --git a/lib/PCA95x5/library.json b/lib/PCA95x5/library.json
new file mode 100644
index 0000000..15ee852
--- /dev/null
+++ b/lib/PCA95x5/library.json
@@ -0,0 +1,20 @@
+{
+    "name": "PCA95x5",
+    "keywords": "i2c,mux,io expander,pca9535,pca9555",
+    "description": "Arduino library for PCA9535 and PCA9555 (Remote 16-bit I2C and SMBus I/O Expander with Interrupt Output and Configuration Registers)",
+    "repository":
+    {
+        "type": "git",
+        "url": "https://github.com/hideakitai/PCA95x5.git"
+    },
+    "authors":
+    {
+        "name": "Hideaki Tai",
+        "url": "https://github.com/hideakitai",
+        "maintainer": true
+    },
+    "version": "0.1.1",
+    "license": "MIT",
+    "frameworks": "arduino",
+    "platforms": "*"
+}
diff --git a/lib/PCA95x5/library.properties b/lib/PCA95x5/library.properties
new file mode 100644
index 0000000..2294e50
--- /dev/null
+++ b/lib/PCA95x5/library.properties
@@ -0,0 +1,9 @@
+name=PCA95x5
+version=0.1.1
+author=hideakitai
+maintainer=hideakitai
+sentence=Arduino library for PCA9535 and PCA9555 (Remote 16-bit I2C and SMBus I/O Expander with Interrupt Output and Configuration Registers)
+paragraph=Arduino library for PCA9535 and PCA9555 (Remote 16-bit I2C and SMBus I/O Expander with Interrupt Output and Configuration Registers)
+category=Device Control
+url=https://github.com/hideakitai
+architectures=*