SDI-12 Sensor Identification Identify what SDI-12 sensor is connected to the bus The SDI-12 address query request is ?! (? asks who is connected, ! is the command terminator). A valid response is in the form of a<CR><LF> where a is the address of the sensor connected. This was introduced in Version 1.2 of the standard […]
Tag Archives: SDI-12
SDI-12 compared to Modbus and NMEA 0183
ReferenceWhich protocol is the best? People may wonder, why use SDI12 when there are other protocols with far wider adaption than SDI12? Two commonly encountered ones are Modbus (in its many varieties such as Modbus-ASCII, Modbus-RTU, Modbus-TCP) and NMEA-0183 There are others like Profibus, HART and Fieldbus (widely used in process control applications), CANBus (automotive), DNP3 (for […]
SDI12 basic command set
ReferenceThe SDI12 command set includes the basic command set as specified by the standard (i.e. V1.1, V1.2, V1.3, V1.4, etc) as well as extended commands which may be included by the manufacturers to add special functionality which is not part of the standard. A common use of the extended commands are to include calibration information. […]
SDI12 interface devices
ReferenceHow do I interface SDI12 to something else? If you are basing your monitoring system on the SDI12 protocol, you will find that not everything that you want to use supports SDI12 (or any one protocol for that matter). From time to time you may need to change protocol. This page provides a link to […]
SDI12 search popularity over time
ReferencePopularity of SDI12 compared to NMEA or Modbus The popularity of SDI12 relative to other serial protocols was investigated to see how it compared to the widely used industrial protocols and changed over time Interestingly, search popularity for all the major protocols has decreased over time, perhaps indicating an increased dominance of non-industrial search terms over time. […]
Version 1.4 of the SDI12 standard
ReferenceSDI12 Version 1.4 Standard Released Available from the SDI-12.org home page, version 1.4 of the standard has been released. http://www.sdi-12.org/current%20specification/SDI-12_version-1_4-August-10-2016.pdf Four new commands have been added: Identify Measurement Commands Identify Measurement Parameter Commands Start High Volume ASCII Measurement Start High Volume Binary Measurement Stay tuned for manufacturers updating their SDI12 sensors