StamPLC IO

IOStamPLC controls the StamPLC IO extension board over I2C.

UiFlow2 Example

Voltage and current monitor

Open the stamplc_io_example.m5f2 project in UiFlow2.

This example sets the two output channels to PWM mode, then displays the voltage and current of channel 0 and channel 1.

UiFlow2 Code Block:

stamplc_io_example.png

Example output:

None

MicroPython Example

Voltage and current monitor

This example sets the two output channels to PWM mode, then displays the voltage and current of channel 0 and channel 1.

MicroPython Code Block:

 1# SPDX-FileCopyrightText: 2026 M5Stack Technology CO LTD
 2#
 3# SPDX-License-Identifier: MIT
 4
 5import os, sys, io
 6import M5
 7from M5 import *
 8from stamplc import IOStamPLC
 9from stamplc import StamPLC
10
11
12title0 = None
13label0 = None
14label1 = None
15stamplc_0 = None
16stamplc_io_0 = None
17
18
19def setup():
20    global title0, label0, label1, stamplc_0, stamplc_io_0
21
22    M5.begin()
23    Widgets.fillScreen(0x000000)
24    title0 = Widgets.Title("StamPLC IO Example", 3, 0xFFFFFF, 0x0000FF, Widgets.FONTS.Montserrat18)
25    label0 = Widgets.Label("label0", 1, 42, 1.0, 0xFFFFFF, 0x222222, Widgets.FONTS.Montserrat18)
26    label1 = Widgets.Label("label1", 2, 71, 1.0, 0xFFFFFF, 0x222222, Widgets.FONTS.Montserrat18)
27
28    stamplc_0 = StamPLC()
29    stamplc_io_0 = IOStamPLC(address=0x20)
30    stamplc_io_0.set_output_mode(IOStamPLC.PWM_MODE)
31    stamplc_io_0.set_pwm_config(0, 1, 100)
32    stamplc_io_0.set_pwm_config(1, 1, 100)
33
34
35def loop():
36    global title0, label0, label1, stamplc_0, stamplc_io_0
37    M5.update()
38    label0.setText(
39        str(
40            (
41                str("ch0:")
42                + str(
43                    (
44                        str((stamplc_io_0.get_voltage(0)))
45                        + str(
46                            (
47                                str("mV")
48                                + str(
49                                    (
50                                        str(", ")
51                                        + str((str((stamplc_io_0.get_current(0))) + str("uA")))
52                                    )
53                                )
54                            )
55                        )
56                    )
57                )
58            )
59        )
60    )
61    label1.setText(
62        str(
63            (
64                str("ch1:")
65                + str(
66                    (
67                        str((stamplc_io_0.get_voltage(1)))
68                        + str(
69                            (
70                                str("mV")
71                                + str(
72                                    (
73                                        str(", ")
74                                        + str((str((stamplc_io_0.get_current(1))) + str("uA")))
75                                    )
76                                )
77                            )
78                        )
79                    )
80                )
81            )
82        )
83    )
84
85
86if __name__ == "__main__":
87    try:
88        setup()
89        while True:
90            loop()
91    except (Exception, KeyboardInterrupt) as e:
92        try:
93            from utility import print_error_msg
94
95            print_error_msg(e)
96        except ImportError:
97            print("please update to latest firmware")

Example output:

None

API

IOStamPLC

class IOStamPLC(i2c=None, address=0x20)

Create a StamPLC IO extension object.

Parameters:

  • i2c – I2C interface. If omitted, the shared StamPLC I2C bus is used.

  • address (int) – I2C address of the StamPLC IO extension.

UiFlow2 Code Block:

init.png

MicroPython Code Block:

from stamplc import IOStamPLC

io = IOStamPLC(address=0x20)
get_voltage(channel)

Get the voltage of one channel.

Parameters:

channel (int) – Channel index, 0 or 1.

Returns:

Voltage in mV.

Return type:

int

UiFlow2 Code Block:

get_voltage.png

MicroPython Code Block:

voltage = io.get_voltage(0)
get_current(channel)

Get the current of one channel.

Parameters:

channel (int) – Channel index, 0 or 1.

Returns:

Current in uA.

Return type:

int

UiFlow2 Code Block:

get_current.png

MicroPython Code Block:

current = io.get_current(0)
get_io_control()

Get the IO control register value.

Returns:

IO control register value.

Return type:

int

set_io_control(value)

Set the IO control register value.

Parameters:

value (int) – IO control register value.

set_solid_relay(channel, state)

Set the solid-state relay output of one channel.

Parameters:

  • channel (int) – Channel index, 0 or 1.

  • state (bool) – True turns the output on, False turns it off.

UiFlow2 Code Block:

set_solid_relay.png

MicroPython Code Block:

io.set_solid_relay(0, True)
get_solid_relay(channel)

Get the solid-state relay output state of one channel.

Parameters:

channel (int) – Channel index, 0 or 1.

Returns:

Output state.

Return type:

bool

UiFlow2 Code Block:

get_solid_relay.png

set_ina226_pullup(channel, enable)

Enable or disable the INA226 pull-up of one channel.

Parameters:

  • channel (int) – Channel index, 0 or 1.

  • enable (bool) – True enables the pull-up, False disables it.

UiFlow2 Code Block:

set_ina226_pullup.png

get_ina226_pullup(channel)

Get the INA226 pull-up state of one channel.

Parameters:

channel (int) – Channel index, 0 or 1.

Returns:

Pull-up state.

Return type:

bool

UiFlow2 Code Block:

get_ina226_pullup.png

set_relay(state)

Set the onboard relay output.

Parameters:

state (bool) – True turns the relay on, False turns it off.

UiFlow2 Code Block:

set_relay.png

get_relay()

Get the onboard relay output state.

Returns:

Relay state.

Return type:

bool

UiFlow2 Code Block:

get_relay.png

set_output_mode(mode)

Set the output mode.

Parameters:

mode (int) – IOStamPLC.OUTPUT_IO_MODE or IOStamPLC.PWM_MODE.

UiFlow2 Code Block:

set_output_mode.png

MicroPython Code Block:

io.set_output_mode(IOStamPLC.PWM_MODE)
get_output_mode()

Get the output mode.

Returns:

IOStamPLC.OUTPUT_IO_MODE or IOStamPLC.PWM_MODE.

Return type:

int

UiFlow2 Code Block:

get_output_mode.png

set_ina226_config(channel, value)

Set the INA226 configuration register of one channel.

Parameters:

  • channel (int) – Channel index, 0 or 1.

  • value (int) – Register value.

get_ina226_config(channel)

Get the INA226 configuration register of one channel.

Parameters:

channel (int) – Channel index, 0 or 1.

Returns:

Register value.

Return type:

int

set_pwm_config(channel, freq, duty)

Set the PWM frequency and duty of one channel.

Parameters:

  • channel (int) – Channel index, 0 or 1.

  • freq (int) – PWM frequency, 1 to 100.

  • duty (int) – PWM duty, 0 to 1000.

UiFlow2 Code Block:

set_pwm_config.png

MicroPython Code Block:

io.set_pwm_config(0, 1, 100)
get_pwm_config(channel)

Get the PWM frequency and duty of one channel.

Parameters:

channel (int) – Channel index, 0 or 1.

Returns:

(freq, duty).

Return type:

tuple

get_firmware_version()

Get the firmware version.

Returns:

Firmware version.

Return type:

int

UiFlow2 Code Block:

get_firmware_version.png

MicroPython Code Block:

version = io.get_firmware_version()
get_i2c_address()

Get the configured I2C address.

Returns:

I2C address.

Return type:

int

UiFlow2 Code Block:

get_i2c_address.png

MicroPython Code Block:

address = io.get_i2c_address()
refresh_i2c_address()

Refresh the active I2C address from the device.