Table of Contents:

• 1. Introduction
  • 1.1 What is SN50v3-NB NB-IoT Sensor Node
  • 1.2 ​Features
  • 1.3 Specification
  • 1.4 Applications
  • 1.5 Sleep mode and working mode
  • 1.6 Button & LEDs
  • 1.7 BLE connection
  • 1.8 Pin Definitions & Switch
    • 1.8.1 Jumper JP2
    • 1.8.2 BOOT MODE / SW1
    • 1.8.3 Reset Button
• 2. Use SN50v3-NB to communicate with IoT Server
  • 2.1 Send data to IoT server via NB-IoT network
  • 2.2  Working Mode & Uplink Payload
    • 2.2.1  CFGMOD=1 (Default Mode)
    • 2.2.2  CFGMOD=2 (Distance Mode)
      • Connection of LIDAR-Lite V3HP:
    • 2.2.3  CFGMOD=3 (3 ADC + I2C)
    • 2.2.4  CFGMOD=4 (3 x DS18B20)
    • 2.2.5  CFGMOD=5 (Weight Measurement by HX711)
    • 2.2.6  CFGMOD=6 (Counting mode)
  • 2.3 ​Payload Types
    • 2.3.1 General Json Format(Type=5)
    • 2.3.2 HEX format Payload(Type=0)
    • 2.3.3 ThingsBoard Payload(Type=3)
    • 2.3.4 ThingSpeak Payload(Type=1)
  • 2.4 Test Uplink and Change Update Interval
  • 2.5 Multi-Samplings and One uplink
  • 2.6 Trggier an uplink by external interrupt
  • 2.7 +5V Output
• 3. Configure SN50v3-NB
  • 3.1 Configure Methods
  • 3.2 AT Commands Set
• 4. Battery & Power Consumption
• 5. Firmware update
• 6. FAQ
  • 6.1 How can I access t BC660K-GL AT Commands?
• 7. Order Info
• 8. ​Packing Info
• 9. Support

1. Introduction

1.1 What is SN50v3-NB NB-IoT Sensor Node

SN50v3-NB is a Long Range NB-IoT Sensor Node.  It is designed to facilitate developers to quickly deploy industrial level NB-IoT solutions. It helps users to turn the idea into a practical application and make the Internet of Things a reality. It is easy to program, create and connect your things everywhere.

SN50v3-NB wireless part is based on NB model allows the user to send data and reach extremely long ranges at low data-rates.It provides ultra-long range spread spectrum communication and high interference immunity whilst minimising current consumption.It targets professional wireless sensor network applications such as irrigation systems, smart metering, smart cities, building automation, and so on.

SN50v3-NB uses STM32l0x chip from ST, STML0x is the ultra-low-power STM32L072xxxx microcontrollers incorporate the connectivity power of the universal serial bus (USB 2.0 crystal-less) with the high-performance ARM® Cortex®-M0+ 32-bit RISC core operating at a 32 MHz frequency, a memory protection unit (MPU), high-speed embedded memories (192 Kbytes of Flash program memory, 6 Kbytes of data EEPROM and 20 Kbytes of RAM) plus an extensive range of enhanced I/Os and peripherals.

SN50v3-NB is an open source product, it is based on the STM32Cube HAL drivers and lots of libraries can be found in ST site for rapid development.

SN50v3-NB supports different uplink methods including MQTT, MQTTs, UDP & TCP for different application requirement, and support uplinks to various IoT Servers.

SN50v3-NB supports BLE configure and OTA update which make user easy to use.

SN50v3-NB is powered by 8500mAh Li-SOCI2 battery, it is designed for long-term use up to several years.

SN50v3-NB has optional built-in SIM card and default IoT server connection version. Which makes it works with simple configuration.

1.2 ​Features

• NB-IoT Bands: B1/B2/B3/B4/B5/B8/B12/B13/B17/B18/B19/B20/B25/B28/B66/B70/B85 @H-FDD
• Ultra-low power consumption
• Open-source hardware / software
• Multiply Sampling and one uplink
• Support Bluetooth v5.1 remote configure and update firmware
• Uplink via MQTT, MQTTs, TCP, or UDP
• Uplink on periodically
• Downlink to change configure
• 8500mAh Battery for long term use
• Nano SIM card slot for NB-IoT SIM

1.3 Specification

Common DC Characteristics:

• Supply Voltage: 2.5v ~ 3.6v
• Operating Temperature: -40 ~ 85°C

I/O Interface:

• Battery output (2.6v ~ 3.6v depends on battery)
• +5v controllable output
• 3 x Interrupt or Digital IN/OUT pins
• 3 x one-wire interfaces
• 1 x UART Interface
• 1 x I2C Interface

NB-IoT Spec:

NB-IoT Module: BC660K-GL

Support Bands:

• B1 @H-FDD: 2100MHz
• B2 @H-FDD: 1900MHz
• B3 @H-FDD: 1800MHz
• B4 @H-FDD: 2100MHz
• B5 @H-FDD: 860MHz
• B8 @H-FDD: 900MHz
• B12 @H-FDD: 720MHz
• B13 @H-FDD: 740MHz
• B17 @H-FDD: 730MHz
• B18 @H-FDD: 870MHz
• B19 @H-FDD: 870MHz
• B20 @H-FDD: 790MHz
• B25 @H-FDD: 1900MHz
• B28 @H-FDD: 750MHz
• B66 @H-FDD: 2000MHz
• B70 @H-FDD: 2000MHz
• B85 @H-FDD: 700MHz

Battery:

• Li/SOCI2 un-chargeable battery
• Capacity: 8500mAh
• Self Discharge: <1% / Year @ 25°C
• Max continuously current: 130mA
• Max boost current: 2A, 1 second

Power Consumption

• STOP Mode: 10uA @ 3.3v
• Max transmit power: 350mA@3.3v

1.4 Applications

• Smart Buildings & Home Automation
• Logistics and Supply Chain Management
• Smart Metering
• Smart Agriculture
• Smart Cities
• Smart Factory

1.5 Sleep mode and working mode

Deep Sleep Mode: Sensor doesn't have any NB-IoT activate. This mode is used for storage and shipping to save battery life.

Working Mode: In this mode, Sensor will work as NB-IoT Sensor to Join NB-IoT network and send out sensor data to server. Between each sampling/tx/rx periodically, sensor will be in IDLE mode), in IDLE mode, sensor has the same power consumption as Deep Sleep mode.

1.6 Button & LEDs

Note: When the device is executing a program, the buttons may become invalid. It is best to press the buttons after the device has completed the program execution.

1.7 BLE connection

SN50v3-NB support BLE remote configure and firmware update.

BLE can be used to configure the parameter of sensor or see the console output from sensor. BLE will be only activate on below case:

• Press button to send an uplink
• Press button to active device.
• Device Power on or reset.

If there is no activity connection on BLE in 60 seconds, sensor will shut down BLE module to enter low power mode.

1.8 Pin Definitions & Switch

SN50v3-NB use the mother board which as below.

1.8.1 Jumper JP2

Power on Device when put this jumper.

1.8.2 BOOT MODE / SW1

1) ISP: upgrade mode, device won't have any signal in this mode. but ready for upgrade firmware. LED won't work. Firmware won't run.

2) Flash: work mode, device starts to work and send out console output for further debug

1.8.3 Reset Button

Press to reboot the device.

2. Use SN50v3-NB to communicate with IoT Server

2.1 Send data to IoT server via NB-IoT network

The SN50v3-NB is equipped with a NB-IoT module, the pre-loaded firmware in SN50v3-NB will get environment data from sensors and send the value to local NB-IoT network via the NB-IoT module.  The NB-IoT network will forward this value to IoT server via the protocol defined by SN50v3-NB.

Below shows the network structure:

There are two version: -GE and -1D version of SN50v3-NB.

GE Version: This version doesn't include SIM card or point to any IoT server. User needs to use AT Commands to configure below two steps to set SN50v3-NB send data to IoT server.

• Install NB-IoT SIM card and configure APN. See instruction of Attach Network.

• Set up sensor to point to IoT Server. See instruction of Configure to Connect Different Servers.  

Below shows result of different server as a glance.

1D Version: This version has 1NCE SIM card pre-installed and configure to send value to DataCake. User Just need to select the sensor type in DataCake and Activate SN50v3-NB and user will be able to see data in DataCake. See here for DataCake Config Instruction.

2.2  Working Mode & Uplink Payload

2.2.1  CFGMOD=1 (Default Mode)

If the cache upload mechanism is turned on, you will receive the payload shown in the figure below.

NOTE:

1. Only up to 10 sets of latest data will be cached.

2. Theoretically, the maximum upload bytes are 215.

• Device ID: f866207058378443 = 866207058378443

• Version: 0x04:dSN50v3-NB,0x64=100=1.0.0

• BAT:  0x0dee = 3566 mV = 3.566V

• Singal:  0x16 = 22

• Model: 0x01 = 1

• Temperature by DS18b20: 0x00f7 = 247/10=24.7

• Interrupt: 0x00 = 0

• ADC: 0x0001 =1= 1.00mv

• Temperature by SHT20/SHT31: 0x00fc = 252 = 25.2 °C

• Humidity by SHT20/SHT31: 0x0232 = 562 = 56.2 %rh

• Timestamp: 64fa7491 =1694135441=2023-09-08 09:10:41

2.2.2  CFGMOD=2 (Distance Mode)

If the cache upload mechanism is turned on, you will receive the payload shown in the figure below.

So the payload is 0xf868411056754138 0078 0ca9 11 02 010b 00 0ca8 0158 60dacc87 

where:

• Device ID: 0xf868411056754138 = 868411056754138

• Version:    0x0078=120=1.2.0

• BAT:      0x0ca9 = 3241mV = 3.241 V

• Singal:  0x11 = 17

• Model: 0x02 = 2

• Temperature by DS18b20: 0x010b= 267 = 26.7  °C

• Interrupt: 0x00 = 0

• ADC: 0x0ca8 = 3240 mv

• Distance by LIDAR-Lite V3HP/Ultrasonic Sensor: 0x0158 = 344 cm

• Timestamp: 0x60dacc87 = 1,624,951,943 = 2021-06-29 15:32:23

Connection of LIDAR-Lite V3HP:

Connection to Ultrasonic Sensor:

Need to remove R1 and R2 resistors to get low power,otherwise there will be 240uA standby current.

2.2.3  CFGMOD=3 (3 ADC + I2C)

ADC1 uses pin PA0 to measure

ADC2 uses pin PA1 to measure

ADC3 uses pin PA4 to measure

If the cache upload mechanism is turned on, you will receive the payload shown in the figure below.

NOTE:

1.    Only up to 10 sets of latest data will be cached.

2.    Theoretically, the maximum upload bytes are 226.

So the payload is 0x f868411056754138 0078 0cf0 12 03 0cbc 00 0cef 010a 024b 0cef 60dbc494 

where:

• Device ID: 0xf868411056754138 = 868411056754138

• Version:    0x0078=120=1.2.0

• BAT:      0x0cf0 = 3312 mV = 3.312 V

• Singal:  0x12 = 18

• Model: 0x03 = 3

• ADC1:  0x0cbc= 3260mV

• Interrupt: 0x00 = 0

• ADC2: 0x0cef =3311 mv

• Temperature by SHT20/SHT31: 0x010a = 266 = 26.6 °C

• Humidity by SHT20/SHT31: 0x024b =587 = 58.7 %rh

• ADC3: 0x0cef = 3311 mv

• Timestamp: 0x60dbc494 = 1,625,015,444= 2021-06-30 09:10:44

2.2.4  CFGMOD=4 (3 x DS18B20)

This mode has total 27 bytes. (Note: Time stamp field are added since firmware version v1.2.0)  As shown below:

If the cache upload mechanism is turned on, you will receive the payload shown in the figure below.

NOTE:

1.    Only up to 10 sets of latest data will be cached.

2.    Theoretically, the maximum upload bytes is 215.

So the payload is 0x f868411056754138 0078 0cdf 15 04 010a 0cde 00 00fb 0100 60dbcb3f  

where:

• Device ID: 0xf868411056754138 = 868411056754138

• Version: 0x0078=120=1.2.0

• BAT:      0x0cdf = 3295 mV = 3.295 V

• Singal:  0x15 = 21

• Model: 0x04 = 4

• Temperature1 by DS18b20: 0x010a = 226 = 22.6 °C

• ADC: 0x0cde = 3294 mv

• Interrupt: 0x00 = 0

• Temperature2 by DS18b20: 0x00fb = 251 = 25.1°C

• Temperature3 by DS18b20: 0x0100  = 256 = 25.6 °C

• Timestamp: 0x60dbcb3f = 1,625,017,151= 2021-06-30 09:39:11

2.2.5  CFGMOD=5 (Weight Measurement by HX711)

Notes about hardware connection:

1. Don't connect the HX711 module VCC to SN50v3-NB 3.3v VCC, in this case, the SN50v3-NB will always power on HX711 and the battery will run out soon.
2. HX711 support 5v VCC, but while connect the SN50v3-NB's +5V to HX711 VCC, the value from HX711 is not stable.
3. Connect SN50v3-NB +5V to HX711 VCC via a LDO module is stable.

Each HX711 need to be calibrated before used. User need to do below two steps:

1. Zero calibration. Don't put anything on load cell and run AT+WEIGRE to calibrate to Zero gram.
2. Adjust calibration factor (default value 400): Put a known weight thing on load cell and run AT+WEIGAP to adjust the Calibration Factor.

For example:

AT+WEIGAP =403.0

Response:  Weight is 401 g

Check the response of this command and adjust the value to match the real value for thing. 

This mode has total 25 bytes. (Note: Time stamp field are added since firmware version v1.2.0). As shown below:

If the cache upload mechanism is turned on, you will receive the payload shown in the figure below.

NOTE:

1.    Only up to 10 sets of latest data will be cached.

2.    Theoretically, the maximum upload bytes are 193.

If we use the MQTT client to subscribe to this MQTT topic, we can see the following information when the NB sensor uplink data.

So the payload is 0x f868411056754138 0078 0c94 14 05 0137 0c93 00 003a 60dbe59e 

where:

• Device ID: 0xf868411056754138 = 868411056754138

• Version:    0x0078=120=1.2.0

• BAT:      0x0c94 = 3220 mV = 3.220 V

• Singal:  0x14 = 20

• Model: 0x05 = 5

• Temperature by DS18b20: 0x0137 = 311 = 31.1 °C

• ADC: 0x0c93 = 3219 mv

• Interrupt: 0x00 = 0

• Weigt by HX711: 0x003a  = 58 g

• Timestamp: 0x60dbe59e = 1,625,023,902= 2021-06-30 11:31:42

2.2.6  CFGMOD=6 (Counting mode)

If the cache upload mechanism is turned on, you will receive the payload shown in the figure below.

NOTE:

1.    Only up to 10 sets of latest data will be cached.

2.    Theoretically, the maximum upload bytes are 160.

• Device ID: 0xf868411056754138 = 868411056754138

• Version: 0x0078=120=1.2.0

• BAT:      0x0cc7 =3271mV =3.271V

• Singal:  0x14 = 20

• Model: 0x06 = 6

• Pulse count:  0x00000002= 2

• Timestamp:  0x60dc03e5 = 1,625,031,653= 2021-06-30 13:40:53

2.3 ​Payload Types

To meet different server requirement, SN50v3-NB supports different payload type.

Includes:

• General JSON format payload. (Type=5)

• HEX format Payload. (Type=0)

• ThingSpeak Format. (Type=1)

• ThingsBoard Format. (Type=3)

User can specify the payload type when choose the connection protocol. Example:

AT+PRO=2,0            // Use UDP Connection & hex Payload

AT+PRO=2,5            // Use UDP Connection & Json Payload

AT+PRO=3,5            // Use MQTT Connection & Json Payload

2.3.1 General Json Format(Type=5)

This is the General Json Format. As below:

{"IMEI":"866207058378443","Model":"SN50V3-NB","mod":1,"battery":3.56,"signal":25,"DS18B20_Temp":-409.5,"digital in":0,"adc1":1,"temperature":0.0,"humidity":0.0,"1":{0.0,0.0,1,-409.5,2023/10/23 05:57:02},"2":{0.0,0.0,1,-409.5,2023/10/23 03:57:12},"3":{0.0,0.0,1,-409.5,2023/10/23 03:42:12},"4":{0.0,64.1,0,-409.5,2023/10/20 09:55:08},"5":{0.0,64.1,0,-409.5,2023/10/20 09:40:08},"6":{0.0,64.1,0,-409.5,2023/10/20 08:26:14},"7":{0.0,64.1,0,-409.5,2023/10/20 08:11:14},"8":{0.0,64.1,0,-409.5,2023/10/20 07:56:14}}

Notice, from above payload:

• Temperature , Humidity , Battery & Signal are the value at uplink time.

• Json entry 1 ~ 8 are the last 1 ~ 8 sampling data as specify by AT+NOUD=8  Command. Each entry includes (from left to right): Temperature, Humidity, Sampling time.

2.3.2 HEX format Payload(Type=0)

This is the HEX Format. As below:

f86620705837844304640ddc1501Ffff0000010000000065360ee60001f0010000000065360b2e0001f001000000006535ef180001f001000000006535eb940000f0010000028165324e7c0000f0010000028165324af80000f00100000281653239a60000f00100000281653236220000f001000002816532329e

Version:

These bytes include the hardware and software version.

Higher byte: Specify Sensor Model: 0x00 for SN50v3

Lower byte: Specify the software version: 0x64=100, means firmware version 1.0.0

BAT (Battery Info):

Ex1: 0x0CBA = 3258mV

Signal Strength:

NB-IoT Network signal Strength.

Ex1: 0x16 = 22

0        -113dBm or less

1        -111dBm

2...30 -109dBm... -53dBm

31      -51dBm or greater

99      Not known or not detectable

Temperature: 

If payload is: 0105H:  (0105 & 8000 == 0), temp = 0105H /10 = 26.1 degree

If payload is: FF3FH :  (FF3F & 8000 == 1) , temp = (FF3FH - 65536)/10 = -19.3 degrees.

(FF3F & 8000: Judge whether the highest bit is 1, when the highest bit is 1, it is negative)

Humidity:   

Read:0295(H)=661(D)    Value:  661 / 10=66.1, So 66.1%

TimeStamp:   

Unit TimeStamp Example: 64d49439(H) = 1691653177(D)

Put the decimal value into this link(https://www.epochconverter.com/) to get the time.

2.3.3 ThingsBoard Payload(Type=3)

Type3 payload special design for ThingsBoard, it will also configure other default server to ThingsBoard.

{"IMEI": "866207058378443", "Model": "SN50V3-NB","mod": 1,"battery": 3.56,"signal": 20,"DS18B20_Temp": 25.9,"digital in": 0,"adc1": 1,"temperature": 0.0,}

2.3.4 ThingSpeak Payload(Type=1)

This payload meets ThingSpeak platform requirement. It includes only four fields. Form 1~6 are:

adc1,Battery,Signal,DS18B20_Temp,Temperature&Humidity. This payload type only valid for ThingSpeak Platform.

As below:

field1=adc_mV value&field2=BAT value&field3=Signal value3&field4=DS18B20_Temp value&field5=Temperature value&field6=Humidity value

2.4 Test Uplink and Change Update Interval

By default, Sensor will send uplinks every 2 hours & AT+NOUD=8

User can use below commands to change the uplink interval.

AT+TDC=600        // Set Update Interval to 600s

User can also push the button for more than 1 seconds to activate an uplink.

2.5 Multi-Samplings and One uplink

To save battery life, SN50v3-NB will sample temperature & humidity data every 15 minutes and send one uplink every 2 hours. So each uplink it will include 8 stored data + 1 real-time data. They are defined by:

• AT+TR=900        // The unit is seconds, and the default is to record data once every 900 seconds (15 minutes, the minimum can be set to 180 seconds)

• AT+NOUD=8     //  The device uploads 8 sets of recorded data by default. Up to 32 sets of record data can be uploaded.

The diagram below explains the relationship between TR, NOUD, and TDC more clearly:

2.6 Trggier an uplink by external interrupt

SN50v3-NB has an external trigger interrupt function. Users can use the PB15 pin to trigger the upload of data packets.

AT command:

• AT+INTMOD         // Set the trigger interrupt mode

• AT+INTMOD=0    // Disable Interrupt

• AT+INTMOD=1    // Trigger by rising and falling edge

• AT+INTMOD=2    // Trigger by falling edge

• AT+INTMOD=3    // Trigger by rising edge

2.7 +5V Output

Control the output duration 5V . Before each sampling, device will

1. first enable the power output to external sensor,

2. keep it on as per duration, read sensor value and construct uplink payload

3. final, close the power output.

AT command: AT+5VT

3. Configure SN50v3-NB

3.1 Configure Methods

SN50v3-NB supports below configure method:

• AT Command via Bluetooth Connection (Recommended): BLE Configure Instruction.

• AT Command via UART Connection : See UART Connection.

3.2 AT Commands Set

AT+<CMD>?           : Help on <CMD>

AT+<CMD>                      : Run <CMD>

AT+<CMD>=<value>      : Set the value

AT+<CMD>=?          : Get the value

General Commands       

AT                    : Attention        

AT?                  : Short Help      

ATZ                 : MCU Reset     

AT+TDC          : Application Data Transmission Interval

AT+CFG          : Print all configurations

AT+5VT           : Set extend the time of 5V power   

AT+PRO          : Choose agreement

AT+APN          : Get or set the APN

AT+EXT           : Get or Set Count value

AT+EXT           : Get or Set Count value

AT+RXDL            : Extend the sending and receiving time

AT+SERVADDR            :   Server Address

AT+WEIGRE              : Get weight or set weight to 0

AT+WEIGAP             : Get or Set the GapValue of weight

AT+DNSCFG            : Get or Set DNS Server

AT+CFGMOD           : Working mode selection

AT+INTMOD            : Set the trigger interrupt mode

AT+GETSENSORVALUE              : Returns the current sensor measurement

AT+CSQTIME            : Get or Set the time to join the network

AT+DNSTIMER            : Get or Set the NDS timer

AT+TLSMOD            : Get or Set the TLS mode

AT+NOUD             : Get or Set the number of data to be uploaded

AT+CDP             : Read or Clear cached data

AT+CUM              : Get or Set cache upload mechanism (0: Off 1: On)

AT+SERVADDR            :   Server Address

UDP Management

AT+CFM  :    Upload confirmation mode (only valid for UDP)

MQTT Management

AT+CLIENT               : Get or Set MQTT client

AT+UNAME              : Get or Set MQTT Username

AT+PWD                  : Get or Set MQTT password

AT+PUBTOPIC          : Get or Set MQTT publish topic

AT+SUBTOPIC          : Get or Set MQTT subscription topic

Information           

AT+FDR              : Factory Data Reset

AT+PWORD        : Serial Access Password

AT+LDATA           : Get the last upload data

AT+CDP               : Read or Clear cached data

4. Battery & Power Consumption

SN50v3-NB use ER26500 + SPC1520 battery pack. See below link for detail information about the battery info and how to replace.

Battery Info & Power Consumption Analyze .

5. Firmware update

User can change device firmware to::

• Update with new features.

• Fix bugs. 

Firmware and changelog can be downloaded from : Firmware download link

Methods to Update Firmware:

• (Recommended way) OTA firmware update via BLE: Instruction.

• Update through UART TTL interface : Instruction.

6. FAQ

6.1 How can I access t BC660K-GL AT Commands?

User can access to BC660K-GL directly and send AT Commands.

See BC660K-GL AT Command set

7. Order Info

Part Number: SN50v3-NB-XX

XX: 

• GE: General version ( Exclude SIM card)

• 1D: with 1NCE* 10 years 500MB SIM card and Pre-configure to DataCake server

YY: The grand connector hole size

• M12: M12 hole

• M16: M16 hole

• M20: M20 hole

8. ​Packing Info

Package Includes:

• SN50v3-NB NB-IoT Sensor Node x 1

• External antenna x 1

Dimension and weight:

• Device Size: 13.0 x 5 x 4.5 cm

• Device Weight: 150g

• Package Size / pcs : 14.0 x 8x 5 cm

• Weight / pcs : 180g

9. Support

• Support is provided Monday to Friday, from 09:00 to 18:00 GMT+8. Due to different timezones we cannot offer live support. However, your questions will be answered as soon as possible in the before-mentioned schedule.

• Provide as much information as possible regarding your enquiry (product models, accurately describe your problem and steps to replicate it etc) and send a mail to Support@dragino.cc.