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chain. If a BAS cannot communicate with one or more MicroTech controllers but the BACnet
Network Diagnostic tool can, the problem is almost certainly on the BAS side of the gateway.
Network Read/Write Tool
The Network Read/Write tool allows you to read from or write to a MicroTech controller in the same
manner that a BACnet BAS would; that is, by using BACnet objects. When you read or write using
BACnet objects, the BACdrop gateway translates the requests and sends them to the specified
MicroTech controllers. This tool can thus be used to test the BACdrop gateway’s point mapping
functions. It can also be used to verify communications to a particular controller. See Figure 24.
Figure 24. Network Read/Write Tool
When you use the Network Read/Write tool, you need at least two documents: (1) a prepared address
schedule that lists each MicroTech controller next to its MicroTech network address and (2) the BDIP
for each controller type to be read from or written to. The BDIP documents list all BACnet objects in
each MicroTech controller type, including engineering units and the meanings of enumerated object
codes (e.g., 1 means “Auto”).
For example, suppose that you want to read the mixed air temperature in the self-contained air
conditioning unit on the 5th floor. The address schedule might tell you this unit is at address 05.00,
and BDIP document BD 08-6 would tell you that the mixed air temperature is Analog Input object 7.
You must also know the MicroTech network number to use the Network Read/Write tool. You can
find the MicroTech network number by using the System Information tool.
Reading from Objects
When you select the Read function at the top of the screen, you can read either the Present_Value
property or the Object_Name property from any BACnet object mapped to any configured
MicroTech controller. After entering all required information, click the Send button and the Setup
Wizard will attempt to gather the data. If successful, a message box that shows the requested
information will appear. If not, the resultant message box will show “unknown object.”
Writing to Objects
When you select the Write function at the top of the screen, you can write the Present_Value property
to any BACnet Analog Output or Binary Output object mapped to any configured MicroTech
controller. After entering all required information, click the Send button and the Setup Wizard will
attempt to write the data. If successful, a message box that says “The write was successful” will
appear. If not, the resultant message box will show “unknown object.”
The write function is somewhat forgiving in that it will automatically round values that have
unsupported resolution and limit values that are outside the object’s valid range. For example, if an
Analog Output object has a resolution of 1°F and a valid range of 40 to 80°F, an entered value of
61.1°F will be written as 61°F and an entered value of 81°F will be written as 80°F.