Hbridge Unit

This library is the driver for Unit HBridge. Only version v1.1 supports current measurement.

Support the following products:

UiFlow2 Example

Motor speed and rotate direction control

Open the cores3_hbridge_motor_control.m5f2 project in UiFlow2.

This example demonstrates how to control the motor’s speed and switch its rotation direction.

UiFlow2 Code Block:

Example output:

None

MicroPython Example

Motor speed and rotate direction control

This example demonstrates how to control the motor’s speed and switch its rotation direction.

MicroPython Code Block:

# SPDX-FileCopyrightText: 2025 M5Stack Technology CO LTD
#
# SPDX-License-Identifier: MIT

import os, sys, io
import M5
from M5 import *
from hardware import I2C
from hardware import Pin
from unit import HbridgeUnit
import time


title0 = None
label0 = None
label_speed = None
i2c0 = None
hbridge_0 = None
speed = None
dir2 = None


def setup():
    global title0, label0, label_speed, i2c0, hbridge_0, speed, dir2
    M5.begin()
    Widgets.fillScreen(0x222222)
    title0 = Widgets.Title("HBridge Motor Control", 3, 0xFFFFFF, 0x0000FF, Widgets.FONTS.DejaVu24)
    label0 = Widgets.Label("Speed:", 35, 60, 1.0, 0xFFFFFF, 0x222222, Widgets.FONTS.DejaVu18)
    label_speed = Widgets.Label("0", 110, 60, 1.0, 0xFFFFFF, 0x222222, Widgets.FONTS.DejaVu18)
    i2c0 = I2C(0, scl=Pin(1), sda=Pin(2), freq=100000)
    hbridge_0 = HbridgeUnit(i2c0, 0x20)
    hbridge_0.set_pwm_freq(1000)
    speed = 0
    hbridge_0.set_direction(0)
    dir2 = True


def loop():
    global title0, label0, label_speed, i2c0, hbridge_0, speed, dir2
    M5.update()
    speed = speed + 1
    label0.setText(str(speed))
    if speed > 99:
        speed = 0
        dir2 = not dir2
        if dir2:
            hbridge_0.set_direction(1)
        else:
            hbridge_0.set_direction(2)
        time.sleep_ms(1000)
    hbridge_0.set_percentage_pwm(speed, 8)
    time.sleep_ms(50)


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")

Example output:

None

API

HbridgeUnit

class unit.hbridge.HbridgeUnit(i2c, address=32)

Bases: object

Create an HbridgeUnit object.

Parameters:

i2c (machine.I2C | PAHUBUnit) – I2C port.
address (int | list | tuple) – HbridgeUnit Slave Address.

UiFlow2 Code Block:

MicroPython Code Block:

from unit import HbridgeUnit

unit_hbridge_0 = HbridgeUnit(i2c0, 0x20)

get_adc_value(raw=0, res=8)

Get ADC value.

This method retrieves the ADC value based on the specified resolution. It supports both 8-bit and 16-bit ADC resolutions. If raw is set to 1, the raw ADC value is returned. Otherwise, the corresponding voltage is calculated and returned.

Parameters:

raw (int) – If 1, returns the raw ADC value. If 0, returns the voltage (calculated based on ADC value).
res (int) – ADC resolution (8 or 16 bits). Default is 8 bits.

Returns:

The raw ADC value or the calculated voltage, depending on raw.

Return type:

float or int

UiFlow2 Code Block:

MicroPython Code Block:

unit_hbridge_0.get_adc_value(raw, res)

get_device_status(mode)

Get device status.

get firmware version and i2c address.

Parameters:: mode (int) – 0xFE and 0xFF
Return type:: int

UiFlow2 Code Block:

MicroPython Code Block:

unit_hbridge_0.get_device_status(mode)

get_driver_config(reg=0)

Get driver config.

Parameters:: reg (int)
Returns:: driver config.
Return type:: int

UiFlow2 Code Block:

MicroPython Code Block:

unit_hbridge_0.get_driver_config(reg)

get_vin_current()

Get the input voltage current (unit: A).

Returns:: The input voltage current value.
Return type:: float

UiFlow2 Code Block:

MicroPython Code Block:

unit_hbridge_0.get_vin_current()

set_16bit_pwm(duty=0)

Set 16-bit pwm duty cycle

Parameters:: duty (int) – pwm duty, range: 0~65535
Return type:: None

UiFlow2 Code Block:

MicroPython Code Block:

unit_hbridge_0.set_16bit_pwm(duty)

set_8bit_pwm(duty=0)

Set 8-bit pwm duty cycle

Parameters:: duty (int) – PWM duty, range: 0~255
Return type:: None

UiFlow2 Code Block:

MicroPython Code Block:

unit_hbridge_0.set_8bit_pwm(duty)

set_direction(dir=0)

Set direction

This method controls the motor’s movement direction or stops it.

Parameters:: dir (int) – Direction control parameter: - 0: Stop - 1: Forward - 2: Reverse
Return type:: None

UiFlow2 Code Block:

MicroPython Code Block:

unit_hbridge_0.set_direction(dir)

set_percentage_pwm(duty=0, res=8)

Set the PWM output based on percentage.

Parameters:

duty (int) – PWM duty cycle as a percentage (0 to 100).
res (int) – PWM resolution (8 or 16 bits), default is 8.

Return type:

None

UiFlow2 Code Block:

MicroPython Code Block:

unit_hbridge_0.set_percentage_pwm(duty, reg)

set_pwm_freq(freq=0)

Set PWM frequency.

Parameters:: freq (int) – The PWM frequnecy.
Return type:: None

UiFlow2 Code Block:

MicroPython Code Block:

unit_hbridge_0.set_pwm_freq(freq)