Xylem iRIS 150 GPRS DATALOGGERS - Manual (Page 26)

iRIS 150 V1.11 User Guide - 20
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5.3.8 Miscellaneous Menu (Level 2)
This menu covers the miscellaneous configuration items.
* Miscellaneous
0 Exit
1 Addr [1]
2 SDI-12 Timing [2573]
3 SDI-12 Terminal
4 Initialise
>
Option 1
When this option is selected you will be prompted to enter the System DO  address for the device.
> Address=
Enter a value between 0 and 32767 (the factory default is 1). This address is used to identify the unit in all
System DO
 communications.
NOTE: An address of 0 is normally reserved for the base station (e.g. HydroTel™ 2000). The iRIS will
always respond to an address of –3, which is a special universal address.
Option 2
The SDI-12 communications protocol defines several timing criteria that all equipment should comply with.
In particular there is a minimum break time before a command in order to allow a sensor to wake up and
respond. Some sensors are slower to wake then others and this can be catered for by issuing retries or
extending the break time. The SDI-12 specification defines a retry sequence to handle slow or non-
responsive sensors. The IRIS SDI-12 function operates in such a way that absolute inter-retry timers may not
be absolute. Therefore a timing adjustment register is provided that allows the pre-command timing to be
extended.
For space reasons this register in fact contains two timing values which are combined into a single number.
Although unfriendly to the average user, it can be easily adjusted. The register value is made up of a break
time and space time, both in milliseconds.
SDI12Timing = (BreakTime *256) + Space Time
The default values are Break Time = 10 and Space Time = 13
So (10 *256) + 13 = 2573 which is the default value.
Normally this register should never need changing, but if a sensor is non-responsive or intermittently
unresponsive, extend the timing out. Typically a value of 19981 will ensure that any sensor type will respond.
Option 3
The SDI-12 terminal mode allows direct access to instruments connected to the SDI-12 interface. This is
useful when a manual check or changes need to be made, such as address changes, scale factors etc.
Knowledge of SDI-12 commands is required to make best use of this feature.
> SDI-12 Terminal mode active. Press to exit
NOTE: This menu option will only appear if one or more sensors have a source set to SDI-12.
When using transparent terminal mode you must press the key after each command or message
you wish to send. Press ESC then Enter to exit the modem terminal session and return to the communication
menu.