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CONTENTS

ATOM DTU NB CN

SKU:K060

Description

ATOM DTU NB CN is a programmable data transmission unit (DTU) with integrated NB-IoT communication function. The built-in SIM7020C module covers most of the Cat-NB frequency bands and integrates the SMA external antenna interface to improve the communication quality and signal stability of the device. Unlike the DTU, which generally only has the function of data transparent transmission, the ATOM DTU series adopts a more open architecture design. The controller ATOM LITE can modify the program at will according to the actual business, and the whole machine reserves a variety of interfaces (RS485, I2C, custom interfaces) for user expansion, which is convenient for the rapid access of sensors and actuators. The self-contained guide rail clamping structure is perfectly embedded in various industrial control sites. ATOM DTU NB CN is very suitable for various low-latency, low-throughput application scenarios (such as remote control, asset tracking, remote monitoring, remote medical treatment, shared bicycles, etc.).

Product Features

  • SIM7020C/Applicable to China

  • RS485 communication interface (with 12V input interface, internal integrated DCDC step-down 5V)

  • Modbus Master/slave

  • Strong signal access capability

  • AT command control

  • SIM card type: MicroSIM

  • External antenna: SMA antenna interface

  • Grove expansion interface:

    • I2C x1
    • Custom x1

  • Serial communication: UART 115200bps

  • Self-contained rail clamping

  • Cat-NB frequency band:

    • B1/B3/B5/B8

  • Data transmission (kbps):

    • 26.15(DL)/62.5(UL)

  • Network protocol:

    • TCP/UDP/LWM2M/COAP/ MQTT/HTTP/HTTPS/ TLS/DTLS/DNS/NTP/ PING/OneNET/Telecom Cloud/Ira Cloud*

Includes

  • 1x ATOM LITE
  • 1x ATOM DTU NB CN
  • 1x SMA antenna
  • 1x SMA red cap
  • 1x M2 hexagon wrench
  • 1x M2x16 screw
  • 1x 3.96-4P terminal
  • 1x NB-IoT flow card (mobile NB flow: 300M/year, valid time: 2021.06.16-2024.05.31)

Application

  • Smart meter
  • Remote monitoring
  • Shared bicycles

Certification

  • RoHS/REACH/CCC/CTA/SRRC/Mobile/Unicom/Telecom/ATEX

Operator certification

  • China Telecom/China Unicom/China Mobile

Specifications

Resources Parameter
Module SIM7020C
Support Cat-NB frequency band B1/B3/B5/B8
Network protocol TCP/UDP/LWM2M/COAP/ MQTT/HTTP/HTTPS/ TLS/DTLS/DNS/NTP/ PING/OneNET/Telecom Cloud/Aila Cloud*
communication UART 115200bps
Net weight 32g
Gross weight 40g
Product Size 64 * 24 * 29mm
Package Size 91 * 42 * 24.5mm

Pin mapping

  • SIMCOM7020C
ATOM G22(TX) G19(RX) 5V GND
SIMCOM7020C RX TX VIN GND
  • RS485
ATOM G23 G33 5V GND
RS485 TX RX VIN GND
  • I2C
ATOM G25 G21 5V GND
I2C SDA SCL VIN GND

Schematic

Example

Arduino

UIFlow

Before using UIFlow programming, you need to burn the UIFlow firmware for the ATOM master, click here to view the quick start tutorial .

Module initialization

Init NB-IoT DTU

  • Initialize the DTU device, this operation will initialize the device serial port and RS485 communication interface.

Power down module

  • Power down the module

Reset module

  • Reset the module, and block the program running until the module reset is complete.

Set command echo mode

  • Set command echo, set whether the communication module will reply a repeated command after receiving the command. True/False

Check module status

  • Check module status

Check single quality

  • Check signal quality

Check network registration

  • Check network registration

Check GPRS network registration

  • Check GPRS network registration

Enable PDP context

  • Enable PDP (Packet Data Protocol)

CoAP

CoAP connect ip port

  • Establish CoAP connection

CoAP GET url security

  • Use the Get method to make resource requests

CoAP POST url payload content format security

  • Use POST method for resource request

CoAP PUT url payload content format security

  • Use PUT method for resource request

CoAP destruction

  • Release CoAP connection

MQTT

MQTT connect server port client id username password keep alive

  • Configure MQTT client information and start the connection.

MQTT disconnect

  • Disconnect MQTT connection

MQTT subscribe topic QoS

  • Subscribe to the topic and configure the QoS level, return value: True (subscription success)/False (subscription failure)

MQTT subscribe callback topic msg

  • Subscription message callback function, when a new subscription message is received, this function will be automatically called and the topic name and data content will be passed

MQTT unsubscribe topic

  • Unsubscribe from a topic

MQTT publish topic payload Qos

  • Publish subject content and configure QoS level

MQTT check connection

  • Check connection status

MQTT poll downlink message

  • Statistics downlink information

RS485

RS485 write a line

  • Write a row of data to the RS485 bus

RS485 write

  • Write data to RS485 bus

RS485 write raw data create list with

  • Write raw data in the form of a list, the default input is decimal, if you need to input hexadecimal data, you need to add 0x prefix, such as 0xff.

RS485 read all

  • Read all data in the serial port buffer

RS485 read characters

  • Read N Byte

RS485 read line

  • Read a line of data in the serial port buffer

Remain cache

  • Judge whether there is data in the serial port buffer area, the return value is the number of data (Byte).

Modbus RTU

Read coils slave address starting address coil qty

  • Read slave coil register data

Read discrete inputs slave address starting address input qty

  • Read the discrete input register data of the slave

Read holding registers slave address starting address register qty signed

  • Read slave holding register data

Read input registers slave address starting address register qty signed

  • Read input register data

Write single coil slave address output address output value

  • Write a single coil

Write single register slave address register address register value signed

  • Write a single holding register

Write multiple coils slave address starting address output value

  • Write multiple coils

Write multiple register slave address starting address register value signed

  • Write multiple holding registers

Usage

Connect to the MQTT server to implement message subscription and publishing. When a new subscription message is received, the callback function will be called and the topic name and data content will be passed, and the output result will be printed to the USB serial port.

Video