# Dragino LSN50 Connection to three SHT31 Sensors **URL:** \ **Category:** Dragino\ **Created:** [November 26, 2020, 7:31pm UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670 "2020-11-26T19:31:51Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![tahmid-sajin](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/tahmid-sajin/32/25844_2.png) [@tahmid-sajin](https://www.thethingsnetwork.org/forum/u/tahmid-sajin)\ **Post date:** [November 26, 2020, 7:31pm UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670/1 "2020-11-26T19:31:51Z")
Hello all, Currently, I am attempting to connect a single Dragino LSN50 sensor node to three SHT31 Sensors. I am wondering if the connection to three sensors from the LSN50 will be possible? If it is possible, how will this alter the code in the LSN50 sensor node and how will the pin connections change with multiple sensors connected to the LSN50? Will this connection influence the battery life? Best regards ---
**Author:** ![descartes](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/descartes/32/47220_2.png) [@descartes](https://www.thethingsnetwork.org/forum/u/descartes)\ **Post date:** [November 26, 2020, 9:48pm UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670/2 "2020-11-26T21:48:42Z")
> [@tahmid-sajin](#): > > I am wondering if the connection to three sensors from the LSN50 will be possible? Yes. If you look at the data sheet, page 8 & 9, it shows how you can dynamically alter the address of each sensor - it will need an I/O pin per sensor. You will need to modify the Dragino supplied base source code to do this and connect the sensors to both the I2C bus as well as one additional output per sensor which seems to be available looking at the LoRa-ST docs. The data sheets show that the sensors don’t consume much when reading, so whilst there will be an impact on the battery, it won’t be much. I’m sure you can look at the data sheet and do some calculations. ---
**Author:** ![tahmid-sajin](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/tahmid-sajin/32/25844_2.png) [@tahmid-sajin](https://www.thethingsnetwork.org/forum/u/tahmid-sajin)\ **Post date:** [November 26, 2020, 10:32pm UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670/3 "2020-11-26T22:32:44Z")
> [@descartes](#): > > Yes. If you look at the data sheet, page 8 & 9 Thank you for your reply. Is the link to the datasheet on the wiki? I was not able to find the data sheet you are refering to. This seems to be the data sheet on their site : ([https://www.dragino.com/downloads/downloads/LSN50-LoRaST/Datasheet\_LSN50\_v2.pdf](https://www.dragino.com/downloads/downloads/LSN50-LoRaST/Datasheet_LSN50_v2.pdf)) If possible, could you please link the data sheet where the sensor’s addresses are altered? Kind regards ---
**Author:** ![descartes](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/descartes/32/47220_2.png) [@descartes](https://www.thethingsnetwork.org/forum/u/descartes)\ **Post date:** [November 26, 2020, 10:55pm UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670/4 "2020-11-26T22:55:56Z")
I’d not expect Dragino to have the data sheets for every sensor available so I asked Ms Google for the datasheet for the SHT31. When connecting sensor Z to MCU Y that’s on device Q, looking at all the data sheets is the winning formula. ---
**Author:** ![tahmid-sajin](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/tahmid-sajin/32/25844_2.png) [@tahmid-sajin](https://www.thethingsnetwork.org/forum/u/tahmid-sajin)\ **Post date:** [December 1, 2020, 9:30pm UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670/5 "2020-12-01T21:30:26Z")
> [@descartes](#): > > You will need to modify the Dragino supplied base source code to do this and connect the sensors to both the I2C bus as well as one additional output per sensor which seems to be available looking at the LoRa-ST docs. Hello, thank you for your help. I am able to understand the ADDR pin alterations for the SHT31 sensor. Now concentrating more on the source code for the task, where can I find the LoRa-ST docs that you are refering to? Kind regards ---
**Author:** ![descartes](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/descartes/32/47220_2.png) [@descartes](https://www.thethingsnetwork.org/forum/u/descartes)\ **Post date:** [December 2, 2020, 11:26am UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670/6 "2020-12-02T11:26:47Z")
> [@tahmid-sajin](#): > > where can I find the LoRa-ST docs that you are refering to? On the Dragino website - the LoRa-ST is the MCU & radio module at the heart of the LSN50 ---
**Author:** ![barylaksebastian](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/barylaksebastian/32/35697_2.png) [@barylaksebastian](https://www.thethingsnetwork.org/forum/u/barylaksebastian)\ **Post date:** [December 11, 2020, 8:47am UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670/7 "2020-12-11T08:47:51Z")
Hi, Has someone tried sht85 on lsn50v2? will it work? ---
**Author:** ![landslidepredictor](https://www.thethingsnetwork.org/forum/letter_avatar_proxy/v4/letter/l/5f8ce5/32.png) [@landslidepredictor](https://www.thethingsnetwork.org/forum/u/landslidepredictor)\ **Post date:** [June 6, 2023, 12:55pm UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670/8 "2023-06-06T12:55:20Z")
Hello, how do we access the lsn50 source code? ---
**Author:** ![Jeff-UK](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/jeff-uk/32/35697_2.png) [@Jeff-UK](https://www.thethingsnetwork.org/forum/u/Jeff-UK)\ **Post date:** [June 6, 2023, 2:12pm UTC](https://www.thethingsnetwork.org/forum/t/dragino-lsn50-connection-to-three-sht31-sensors/41670/9 "2023-06-06T14:12:52Z")
erm…by looking at the Dragino site?! Had you even tried before asking? 🤷‍♂️ Hint: > **[LSN50-V2 -- Waterproof Long Range Wireless LoRa Sensor Node](https://www.dragino.com/products/lora-lorawan-end-node/item/155-lsn50-v2.html)** > > LoRaWAN End node gets you to tab for documents (near the bottom of page) which gets you to link for open source (at the bottom of page) which gets you to here from software (last item!) > **[GitHub - dragino/LoRa\_STM32: Source code for Dragino LoRa module base on...](https://github.com/dragino/LoRa_STM32)** > > Source code for Dragino LoRa module base on STM32 Chip - GitHub - dragino/LoRa\_STM32: Source code for Dragino LoRa module base on STM32 Chip Your welcome 🙂