VA's -Virtual Addresses are used by CoolAutomation devices in order to simplify translation of the Indoor Unit number - UID into Instance Number of the BACnet Object Identifier.
UID is a string in format Ln.XYY. For Example:
L1.102 - Indoor Unit 102 on line L1
L2.003 - Indoor Unit 003 on line L2
List of UID's detected (visible) by CoolAutomation device can be retrieved with ls command.
L1.100 ON 19C 30C High Fan OK # 0
L1.101 OFF 28C 23C High Cool OK - 0
Each UID can have none, one or a number of associated VA's. VA's are plain numbers starting from 1. Device can automatically allocate and associate VA's with existing (visible by ls command) UID's:
To query allocated VA's use va command without parameters:
L1.100 --> 0001 [Hex: 0x0011 | Dec: 00017]
L1.101 --> 0002 [Hex: 0x0021 | Dec: 00033]
In example above UID L1.100 has a VA=0001 and UID L1.101 has a VA=0002. Numbers is '[' ']' braces are not applicable for BACnet modules (they are used for Modbus modules).
VA's can be allocated or deallocated (deleted) all together or separately. As shown above for automatic VA's allocation va auto command is used. It is possible to allocate VA for specific UID. For example, allocate VA 0004 for UID L1.102:
>va + L1.102 0004
In this case UID does not have to be detected (visible) by CoolAutomation device at the VA allocation time. It is allowed to allocate a number of VA's for any given UID.
To delete all allocated VA's:
Specific VA can also be deleted (below command will delete VA 0004):
>va - 0004
Alternatively all VA's associated with specific UID can be deleted (below command will delete all VA's associated with UID L1.102):
>va - L1.102
Once VA's are allocated BACnet MS/TP and/or BACnet IP can be used to access Indoor Unit parameters. Translation of the VA into Instance Number of the BACnet Object Identifier is made according to the scheme below:
|Object Identifier bits|