Key benefits Expand or mix inputs and outputs on a single board: 16 channels, each independently configurable as input or output to handle sensors, switches, and indicators in the same module. Reduce component count and wiring: each IO port can source or sink up to 25 mA, allowing many common devices (LEDs, logiclevel inputs, small sensors) to connect directly without extra drivers. Fast and flexible communication: multispeed I2C support (100 kHz, 400 kHz, and 7 MHz) improves responsiveness for timesensitive projects. Easily scale systems: three address pins let you use up to eight modules on one bus, providing up to 128 IO ports for larger control and monitoring tasks. What it does and why it helps Function: Provides 16 programmable I/O channels on a single I2Caddressable module. Each channel can be set independently as an input or output to match your application needs. Compatibility: Uses the I2C bus so it works with standard microcontrollers and development boards that support I2C (for example: Arduino, Raspberry Pi, ESP32). Three address pins let multiple modules share the same bus without conflict. Performance: Perport drive capability is up to 25 mA, enabling direct connection to many LEDs, indicators, and logic loads. Multispeed I2C (100 kHz / 400 kHz / 7 MHz) lets you choose the right tradeoff between range and throughput for your system. Expandability: With up to eight modules per I2C bus, you can grow from 16 IOs to 128 IOs without complex wiring changes. Practical details to consider Each channel is independently configurable as input or output, so one board can monitor switches and drive indicators at the same time. Ports support up to 25 mA per channel; highercurrent devices should be driven through external transistors or drivers. Addressing: three hardware address pins allow up to eight unique module addresses on the same I2C bus. Communication modes: compatible with standard I2C operation at 100 kHz and 400 kHz, and also supports a 7 MHz mode for higher throughput where supported by your host. Typical use scenarios Home automation: Add dozens of status LEDs, door/window sensors, and switch inputs to a single controller without using many digital pins. Prototyping and education: Quickly expand IO for classroom experiments, lab setups, or development boards when the onboard pins are exhausted. Robotics and machine control: Read multiple limit switches and drive indicator LEDs or logiclevel control lines; use external transistors or motor drivers for highercurrent actuators. What makes this module stand out Perchannel flexibility (input or output) for mixedsignal tasks. Relatively perchannel drive (25 mA) reduces the need for intermediate components for common loads. Wide I2C speed support including a speed 7 MHz option for latencysensitive applications. Simple hardware addressing for straightforward multimodule expansion up to 128 IOs. Compatibility notes Intended for systems with an I2C master. Confirm your microcontroller or host supports the chosen I2C speeds before using the 7 MHz mode. Use external drivers or transistors for loads requiring more than 25 mA per channel. Specifications (as provided) 16 configurable IO channels (each input or output) 25 mA maximum per IO port I2C speeds: 100 kHz, 400 kHz, 7 MHz Three address pins — up to eight modules (128 IOs total)