NB-IoT2 Unit

The NB-IOT2 Unit is a wireless communication module suitable for global Cat-NB frequency bands. It features an integrated SIM7028 communication module, utilizing serial communication (controlled via AT commands).

Support the following products:

Micropython Example:

import os, sys, io
import M5
from M5 import *
from unit import NBIOT2Unit
import time

def nbiot2_0_SubTopic_event(_topic, _msg):
    print(_topic)
    print(_msg)

nnbiot2_0 = NBIOT2Unit(2, port=(18, 17))
while not (nbiot2_0.get_gprs_network_status()):
    time.sleep(2)
nbiot2_0.mqtt_server_configure('mqtt.m5stack.com', 1883, 'm5-mqtt-2024', '', '', 120)
nbiot2_0.mqtt_subscribe_topic('SubTopic', nbiot2_0_SubTopic_event, 0)

while True:
    nbiot2_0.mqtt_polling_loop()

UIFLOW2 Example:

cores3_nbiot2_example.m5f2

class NBIOT2Unit

Constructors

class NBIOT2Unit(id, port=(, ))

Create a NBIOT2Unit object

The parameters is:

• id uart object of the given id: 0~2 and default is 2.

• port uart pin tuple, which contains: (tx_pin, rx_pin).

UIFLOW2:

Methods

NBIOT2Unit.check_modem_is_ready()

To check whether the communication with the NBIOT unit has been successful.

• Return: bool: True or False

UIFLOW2:

NBIOT2Unit.get_imei_number()

Get the International Mobile station Equipment Identity(IMEI) number.

• Return: string

UIFLOW2:

NBIOT2Unit.get_signal_strength()

Get the received signal strength indication level.

• Return: int:

  Int	Rx signal strength level
  0	-110 dBm or less
  1	-109 dBm <=rssi< -107 dBm
  2	-107 dBm <=rssi< -105 dBm
  3…30	-105 dBm <=rssi< -48 dBm
  31	-48 dBm <=rssi
  99	Not known or not detectable

UIFLOW2:

NBIOT2Unit.get_model_identification()

Get the product model identification.

• Return: string: SIMxxxx

UIFLOW2:

NBIOT2Unit.get_gprs_network_status()

Get the Indicates the Status of GPRS/Packet Domain Attached or Detached.

• Return: int: 0 ~ 1

  Int	Status
  0	Detached
  1	Attached

UIFLOW2:

NBIOT2Unit.get_show_pdp_address_cid(cid)

Get the requests of PDP address for context identifier(0~1)

The parameters is:

• cid: 0 ~ 1

UIFLOW2:

NBIOT2Unit.get_pdp_context_dynamic_parameters(param)

Get the PDP Context Read Dynamic Network Parameters.

The parameters is:

• param: IP: 1, APN: 2.

UIFLOW2:

NBIOT2Unit.set_command_echo_mode(state)

Set the Command Echo Mode Off or On

The parameters is:

• state: Off: 0, On: 1.

UIFLOW2:

NBIOT2Unit.set_gprs_network_state(enable)

Set the State of GPRS/Packet Domain Attached or Detached.

The parameters is:

• enable: Detached: 0, Attached: 1.

UIFLOW2:

NBIOT2Unit.set_pdp_context_apn(apn)

Set the Default PSD Connection Settings.

The parameters is:

• apn: apn a string parameter and “cmnbiot” is default

UIFLOW2:

NBIOT2Unit.modem_debug = True/False

Set the AT Command debug print enable or disable.

The parameters is:

• modem_debug: disable: False, enable: True.

UIFLOW2:

NBIOT2Unit.mqtt_server_configure(server, port, client_id, username, passwd, keepalive)

Set the MQTT Server address, port number, client id, username, password and keepalive time of the MQTT server.

The parameters is:

• server: server address is string format

• port: port number is int format

• client_id: client id is string format

• username: username is string format

• passwd: password is string format

• keepalive: seconds is int format

UIFLOW2:

NBIOT2Unit.mqtt_subscribe_topic(topic, cb, qos)

Specifies the subscription topic to subscribe.

The parameters is:

• topic: string format

• cb: callback function is called when a message has been received on a topic

• qos: 0 ~ 2 (Default is 0)

Note

When using this block, the “mqtt_server_configure” block must be set after this block

UIFLOW2:

An handler showing a message has been received:

def nbiot2_0_xxxxxxxx_event(_topic, _msg):
    print("topic:", _topic)
    print("msg:", _msg)

On uiflow2, you can get the topic and message of the current handler through and .

NBIOT2Unit.mqtt_server_connect(clean_session)

Connect the MQTT Server.

The parameters is:

• clean_session: The clean session flag. The value range is from 0 to 1, and default value is 0.

UIFLOW2:

NBIOT2Unit.mqtt_server_disconnect()

Disconnect the MQTT Server

Note

“mqtt server connect” must be set before this block for it to work effectively.

UIFLOW2:

NBIOT2Unit.mqtt_server_is_connect()

Check the MQTT Server Connection Status

• Return: int: 0 ~ 1

  Int	Status
  0	Not connected
  1	Connected

UIFLOW2:

NBIOT2Unit.mqtt_unsubscribe_topic(topic)

Unsubscribed topic to the MQTT server.

The parameters is:

• topic: topic is string format

UIFLOW2:

NBIOT2Unit.mqtt_publish_topic(topic, payload, quality)

Set the published topic and message to the MQTT server.

The parameters is:

• topic: topic is string format

• payload: payload is string format

• quality: quality of service of 0, 1, 2

UIFLOW2:

NBIOT2Unit.mqtt_polling_loop()

The mqtt polling loop block must be used inside a loop.

UIFLOW2:

NBIOT2Unit.http_request(method, url, headers, data)

Create an HTTP or HTTPS request and set the configuration.

The parameters is:

• method: GET: 0, POST: 1

• url: HTTP server host is string format

• headers: headers is Dictionaries type

• data: data is Dictionaries type

UIFLOW2:

NBIOT2Unit.http_terminate()

HTTP service terminated

Note

“http_request” must be set before this block for it to work effectively.

UIFLOW2:

NBIOT2Unit.data_content()

Get the HTTP content data of the response from the host

• Return: string: Content data is string

UIFLOW2:

NBIOT2Unit.response_code()

Get the HTTP response code

• Return: int: 100, 101, 200 … 504, 505

UIFLOW2: