YSI WaterLog Series, Руководство пользователя

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SDI-12 Transparent Mode
The SDI-12 Transparent and Monitor Mode enables the System 5000 to not only issue
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commands from the unit itself, but also view all traffic on the SDI-12 lines. This allows the
System 5000
to talk directly with and test any SDI-12 sensors on the line. All SDI-12 sensors
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must implement a set of standard commands. These standard commands can be sent to a sensor
using a single button press. Extended or additional commands specific to each sensor may also
be sent to a sensor through the Extended CMD mode accessed through the function button.
Sensor Address: Defines the sensor address that will be prefixed on most SDI-12 commands
issued. Sensor addresses are case-sensitive and can be any alphanumeric character. If the
address is unknown, the Query Address buttons for a single sensor or Identify Sensors Test
button can be used to help identify the sensor’s address.
Change Address To: Sets the current sensor address to a new address. For example, if the
existing Sensor Address was 0 and needed to be changed to 1, by pressing the Edit button next to
this label, entering 1, and pressing OK would issue an address change command of ‘0A1!’. The
sensor would now respond to address 1 rather than 0.
Query Address: Two options here provide generic querying of addresses on the SDI-12 line. If
a single sensor is connected, one or both of these commands (‘?!’ and ‘*!’) should trigger a
response from the SDI-12 sensor, returning the address of the sensor itself. If multiple sensors
exist, a collision will probably occur resulting in a garbled response.
Identify Sensors(0-9)/(A-Z): Used to automatically search for SDI-12 sensors on the SDI-12
line. Identify (I!) requests will be sent out for the selected range (0-9 or A-Z). The querying and
any responses will be shown in the above window. If a sensor is found, it will list its response to
the ID command which should include the manufacturers name, model number of the sensor, and
version information. If two or more sensors use the same address, a collision will probably occur
resulting in a garbled response.
11-8 System Setup - Communications
System 5000
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