M5Stack Byte Switch Unit with 8x Switches (STM32G031)

M5Stack Byte Switch Unit for 8-Channel Physical Input

The M5Stack Byte Switch Unit combines eight independent DPDT toggle switches, nine addressable RGB LEDs, and an STM32G031G8U6 controller in one compact input panel. It is designed for applications that need persistent physical switch states with immediate visual feedback.

The unit communicates through I2C at address 0x46 and provides two Grove I2C ports for bus expansion. This reduces host GPIO usage and makes it easier to add a bank of physical controls to an M5Stack controller or another compatible embedded host.

Read 8 Toggle States Through One I2C Device

Each switch can represent an enable flag, mode selection, channel state, scene selection, test condition, or other binary control. Because a mechanical toggle retains its position, the physical panel can show the commanded state even before a display is read. Design the firmware so startup behavior clearly defines whether hardware position overrides stored software state.

Use RGB LEDs for Status Feedback

Nine WS2812C-2020 RGB LEDs can indicate channel state, warnings, active modes, or interaction feedback. Keep color meanings consistent across the interface and include a non-color cue when the state is critical, since color alone may not be sufficient for every operator.

Cascade I2C Devices Carefully

The two Grove ports support I2C bus expansion. Before combining multiple units or sensors, check address conflicts, total pull-up resistance, cable length, bus capacitance, and power distribution. I2C is best suited to local embedded connections rather than long industrial cable runs.

Build Clear Control Panels

The Byte Switch Unit fits smart-home panels, game controllers, education platforms, laboratory fixtures, interactive exhibits, instrument interfaces, and portable debugging tools. Label each switch according to the real function and avoid assigning safety-critical emergency functions to a general-purpose I2C input device.

Technical setup details are available in the M5Stack ByteSwitch documentation.