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2024-01-22 at 3:30 PM
#18301
@bibhutibikramaditya Exactly what output are you getting? You’re not asking for data in your script, so you should only be getting a response like “00013” not any data values.
Sug
@bibhutibikramaditya Exactly what output are you getting? You’re not asking for data in your script, so you should only be getting a response like “00013” not any data values.
Suggestions:
- Confirm that the data pin of the Hydros 21 sensor is plugged into the correct pin
- Confirm the sensor has power
- Confirm that you’re serial port monitor is monitoring at the correct baud rate. (Your program uses 9600; many of the SDI-12 library examples use 115200 or 57600.)
- Use the SDI-12 example program B (https://github.com/EnviroDIY/Arduino-SDI-12/tree/master/examples/b_address_change) to change the Hydros-21’s SDI-12 address from 0 to 1 or some other valid address. (Not required, but strongly recommended in Meter’s documentation: https://library.metergroup.com/Integrator%20Guide/18281_HYDROS21(CTD)_GEN1.pdf .)
- Try the SDI-12 example program D (https://github.com/EnviroDIY/Arduino-SDI-12/tree/master/examples/d_simple_logger) to see if you can get data from that.
- Rewrite your program to both request that a measurement is started (aM!) and request data from that measurement (aD0!) – where ‘a’ is the sensor’s SDI-12 address.
