Faces Calculator3 Module

Faces Calculator3 is a calculator keypad module. It reports released key codes through a callback and uses I2C address 0x08 by default.

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UiFlow2 Example

Key event display

This example reports the key released on the CoreS3 display. The callback receives the released key code, converts it to a character, and displays it.

Open the faces_calculator3_cores3_example.m5f2 project in UiFlow2.

UiFlow2 Code Block:

MicroPython Example

Key event display

Call FacesCalculator3Module.tick() regularly from the main loop to poll for new key events.

# SPDX-FileCopyrightText: 2026 M5Stack Technology CO LTD
#
# SPDX-License-Identifier: MIT

import os, sys, io
import M5
from M5 import *
from module import FacesCalculator3Module


title0 = None
label0 = None
faces_calculator3_0 = None


event_args = None


def faces_calculator3_0_key_event(args):
    global title0, label0, faces_calculator3_0, event_args
    event_args = chr(args)
    label0.setText(str((str("Key: ") + str(event_args))))


def setup():
    global title0, label0, faces_calculator3_0, event_args

    M5.begin()
    Widgets.setRotation(1)
    Widgets.fillScreen(0x222222)
    title0 = Widgets.Title(
        "Faces Calculator3 CoreS3 Example", 3, 0xFFFFFF, 0x0000FF, Widgets.FONTS.Montserrat18
    )
    label0 = Widgets.Label("label0", 1, 112, 1.0, 0xFFFFFF, 0x222222, Widgets.FONTS.Montserrat18)

    faces_calculator3_0 = FacesCalculator3Module(address=0x08)
    faces_calculator3_0.set_callback(faces_calculator3_0_key_event)


def loop():
    global title0, label0, faces_calculator3_0, event_args
    M5.update()
    faces_calculator3_0.tick()


if __name__ == "__main__":
    try:
        setup()
        while True:
            loop()
    except (Exception, KeyboardInterrupt) as e:
        try:
            from utility import print_error_msg

            print_error_msg(e)
        except ImportError:
            print("please update to latest firmware")

API

class module.faces.FacesCalculator3Module(address=8)

Bases: _FacesModule

Create a Faces Calculator3 Module object.

Parameters:: address (int) – I2C address. Default is 0x08.

UiFlow2 Code Block:

MicroPython Code Block:

from module import FacesCalculator3Module

faces_calculator3 = FacesCalculator3Module()

set_callback(handler)

Set the callback for key events.

The callback receives the released key code. Pass None to disable it.

Parameters:: handler – Callable accepting one key code, or None.
Return type:: None

tick()

Poll once and invoke the callback when a key event is available.

UiFlow2 Code Block:

MicroPython Code Block:

faces_calculator3.tick()

Return type:: None

get_device_id()

Get the Faces module device type ID.

Returns:: The device type ID.
Return type:: int

UiFlow2 Code Block:

MicroPython Code Block:

device.get_device_id()

get_firmware_version()

Get the firmware version.

Returns:: The firmware version.
Return type:: int

UiFlow2 Code Block:

MicroPython Code Block:

device.get_firmware_version()

get_i2c_address()

Get the current 7-bit I2C address.

Returns:: The current I2C address.
Return type:: int

UiFlow2 Code Block:

MicroPython Code Block:

device.get_i2c_address()

get_uid()

Get the 96-bit MCU unique identifier.

Returns:: The 12-byte unique identifier.
Return type:: bytes

UiFlow2 Code Block:

MicroPython Code Block:

device.get_uid()

set_i2c_address(address)

Set and persist a new 7-bit I2C address.

Parameters:: address (int) – New address in the range 0x08 to 0x77.
Return type:: None

UiFlow2 Code Block:

MicroPython Code Block:

device.set_i2c_address(0x08)

Calculator key constants:

Constant	Value	Key
`KEY_BACKSPACE`	`0x08`	Backspace
`KEY_ENTER`	`0x0D`	Enter
`KEY_AC`	`0x41`	All clear
`KEY_MEMORY`	`0x4D`	Memory
`KEY_PERCENT`	`0x25`	Percent
`KEY_DIVIDE`	`0x2F`	Divide
`KEY_MULTIPLY`	`0x2A`	Multiply
`KEY_MINUS`	`0x2D`	Minus
`KEY_PLUS`	`0x2B`	Plus
`KEY_SIGN`	`0x60`	Sign
`KEY_EQUAL`	`0x3D`	Equal