Campbell Scientific CR510 Basic Datalogger - Manual (Page 117)

SECTION 9. INPUT/OUTPUT INSTRUCTIONS
9-13
01: SDI-12 Recorder (P105)
1:
1 SDI-12 Address
2: 0 Start Measurement (aM0!)
3: 1 Port
4: 5 Loc [ SendVal_1 ]
5: 1 Mult
6: 0 Offset
02: Extended Parameters 4 Digit (P68)
1:
65 Option ;ASCII character A
2: 48 Option ;ASCII character 0
3: 128 Option ;Send first value
4: 128 Option ;Send second value
5: 0 Option ;End of command string
6: 0 Option
7: 0 Option
8: 0 Option
PARAMETER 3. PORT
Enter the CR510 control port (C1, C2)
connected to the SDI-12 sensor data line.
PARAMETER 4. INPUT LOCATION
Input location where the returned data is stored.
If multiple values are returned from the SDI-12
sensor they are stored in sequential input
locations beginning at the specified location.
ERRORS
If the CR510 receives either an incorrect
response or no response from an SDI-12
sensor, the CR510 will retry the operation. If
after retries a valid response has not been
received, the CR510 will store a -99999 in the
input location specified in Parameter 4. Only
the first location will be altered. Sequential
locations will contain values from previous
measurements.
TRANSPARENT MODE
The SDI-12 transparent mode is used to
communicate directly with an SDI-12 sensor. A
common application of the transparent mode is
to verify proper operation of the SDI-12 sensor.
A computer or terminal is required to use the
transparent mode; the CR10KD (keyboard
display) cannot be used. Transparent mode is
entered while the computer is in
telecommunications with the SDI-12 recorder
CR510 (at the asterisk '
∗
' prompt). Enter 'pX' at
the asterisk prompt, where 'p' is the Control Port
number (1, 2) attached to the SDI-12 data line.
The CR510 responds with ‘entering SDI-12.’
Any SDI-12 command preceded with the sensor
address and followed with an exclamation point
'!' may then be entered. For example, entering
'0I!' would request identification from an SDI-12
sensor addressed at 0.
The SDI-12 prompt will not appear until the
CR510 finishes executing all program tables.
While in transparent mode, scheduled tables in
the CR510 will not execute. Transparent mode
ends and the ‘*’ prompt is returned when an
invalid SDI-12 command (e.g., a blank line) is
entered, if the SDI-12 sensor doesn’t respond
within the time-out period following a valid
command (approximately 1/3 second), or if the
user does not enter a command before the
mode times out (approximately 35 seconds).
Security must be unlocked to level 2 before the
Transparent mode is enabled.
*** 106 SDI-12 SENSOR ***
Instruction 106 allows a CR510 to be used as
an SDI-12 sensor. The CR510 can make
measurements and transfer data using SDI-12
commands in response to another SDI-12
recorder.
Instruction 106 supports the Standard SDI-12
commands as listed in the Parameter 2
description for Instruction 105.
The SDI-12 data line is attached to Control Port
2 and Instruction 106 must be the first
instruction in Subroutine 98 located in Table 3.
An SDI-12 recorder addresses the SDI-12
sensor CR510 by sending a Break and the
sensor's address. The sensor CR510 will call
subroutine 98 whenever it detects activity on the