Campbell Scientific CS475, CS476, and CS477 Radar Water Level Sensor - Manual (Page 39)

Appendix B. SDI-12 Commands/
Changing Settings
The SDI-12 commands are entered using the 25616, Adjustment/Display
Module, or the terminal emulator in LoggerNet or PC400 (see Appendix B.2,
Using Terminal Emulator and a Datalogger to Send Commands). These
commands are also used in CRBasic or Edlog programming (see Section 7.5,
Programming).
SDI-12 commands have three components:
Sensor address (a) – a single ASCII character, and is the first character of the
command. The sensor address allows multiple sensors to be connected to a
single control port. The default address is zero, and typically is only changed
when multiple sensors are connected to the same port. Valid addresses are 1 to
9, A to Z, or a to z.
Command body (e.g., M1) – an upper case letter (the “command”) followed by
alphanumeric qualifiers.
Command termination (!) – an exclamation mark.
An active sensor responds to each command. Responses have several standard
forms and terminate with <CR><LF> (carriage return – line feed). SDI-12
commands supported by the radar sensors are listed in TABLE B-1.
B-1