# BM Sensor Integration - SDI-12 Multiparameter Sonde EXO3s **URL:** \ **Category:** Projects\ **Tags:** documentation\ **Created:** [August 13, 2024, 7:25pm UTC](https://bristlemouth.discourse.group/t/bm-sensor-integration-sdi-12-multiparameter-sonde-exo3s/399 "2024-08-13T19:25:58Z")\ **Posts on this page:** 1\ **Showing post:** 3
**Author:** ![umakat](https://yyz1.discourse-cdn.com/flex029/user_avatar/bristlemouth.discourse.group/umakat/32/215_2.png) [@umakat](https://bristlemouth.discourse.group/u/umakat)\ **Post date:** [August 15, 2024, 10:21pm UTC](https://bristlemouth.discourse.group/t/bm-sensor-integration-sdi-12-multiparameter-sonde-exo3s/399/3 "2024-08-15T22:21:26Z")
## Basic SDI-12 commands and responses After wiring as mentioned above, I used `pyserial-miniterm` to find the sensor and connect to it (any serial terminal should work). I also added `echo` to view the commands I type to send. I noticed I receive the response immediately after typing `!` at the end of the command to send. Here is what I saw on the terminal. The EXO3s Multi-parameter Sonde shows up as a USB port with description: `/dev/cu.usbserial-D30FEU73 'FT231X USB UART - FT231X USB UART'` > uma@Umas-MacBook-Pro-2 ~ % pyserial-miniterm -e > — Available ports: > — 1: /dev/cu.BLTH ‘n/a’ > — 2: /dev/cu.Bluetooth-Incoming-Port ‘n/a’ > — 3: /dev/cu.usbserial-D30FEU73 ‘FT231X USB UART - FT231X USB UART’ > — Enter port index or full name: 3 > — Miniterm on /dev/cu.usbserial-D30FEU73 9600,8,N,1 — > — Quit: Ctrl+] | Menu: Ctrl+T | Help: Ctrl+T followed by Ctrl+H — > ␀?!0 > 0!0 > 0I!013YSIIWQSGEXOSND100 > 0M!00629 > 0 > 0D!0 > 0D0!0+0.098+22.783+5.50+6.87 > 0D1!0-7.13+83.10+7.16+5.95 > 0D2!0+1.22+12.41 > 0D3!0 ### Breaking it down - I used [this website](https://help.campbellsci.com/cs650-cs655/shared/sdi-12-sensor-support/sdi-12-command-basics.htm?tocpath=SDI-12%20sensor%20support%7CSDI-12%20command%20basics%7C _____ 0) to look up SDI-12 commands since it’s easy to read. | command | response | interpretation | | --- | --- | --- | | ?! | 0 | _Address Query:_ `0` is the address | | 0! | 0 | _ACK:_ `0` is the address | | 0I! | 013YSIIWQSGEXOSND100 | _Identification:_ `0` sdi-12 sensor address; `13` sdi-12 version number; `YSIIWQSG` vendor identification; `EXOSND` sensor model; `100` sensor version | | 0M! | 00629 | _Measure command:_ `0` sdi-12 sensor address; `062` time is seconds until data available; `9` number of value to expect after `62` seconds (`0` will be rxd to indicate measurement is done) | | 0D0! | 0+0.098+22.783+5.50+6.87 | _Send Data command from channel `0`:_ `0` sdi-12 sensor address; `0.098` value 1; `22.783` value 2; `5.50` value 3; `6.87` value 4 | | 0D1! | 0-7.13+83.10+7.16+5.95 | _Send Data command from channel 1:_ `0` sdi-12 sensor address; `-7.13` value 5; `83.10` value 6; `7.16` value 7; `5.95` value 8 | | 0D2! | 0+1.22+12.41 | _Send Data command from channel 2:_ `0` sdi-12 sensor address; `1.22` value 9; `12.41` value 10? | ## Next Steps The next step is understanding this data. Some questions that came up after getting this data – - What do the values mean? - In what order are they being sent? - Can I configure them and choose which reading is sent first? - Does the position of the sensors inside the sonde matter? After having a little back and forth with the YSI support team, I understand I would need to use their [Kor Software](https://www.ysi.com/kor-software?srsltid=AfmBOooZaQwozooXZNvleUYCPGRilUQ6M3KCeeDsx6LhFcQF7BlGq4dA) and along with their [DCP Signal Output Adapter](https://www.ysi.com/product/id-599820/exo-dcp-signal-output-adapter-2-0?srsltid=AfmBOoosiYI6nhYcufGQ16CVrvBbJaS9DAWwe0eIfWWYGEako0ygBLl7) to configure the data frames being sent from the sonde. My next post will be about my discoveries using the Kor software + DCP SOA with the EXO3s. --- _[View the full topic](https://bristlemouth.discourse.group/t/bm-sensor-integration-sdi-12-multiparameter-sonde-exo3s/399)._