The BACnet driver enables the gateways device to be either BACnet client or BACnet server. It supports following standards: BACnet IP,BACnet/SC, BACnet Ethernet as well as BACnet MS/TP. The device offers - if needed - BBMD -(BACnet Management Broadcast Device) and FD- (Foreign Device) functionalities.
The BACnet driver is named: bac
The Routing address of the first BACnet driver is 940
The data point file for the first BACnet driver is named: bac1.txt
The configuration file for global setting of the first BACnet driver is called: bac1.cfg
For the BACnet driver as well as all other gateway drivers the data point definitions are as follows:
|M||Integer value (binary data points, counters) which can/shall only be read by the gateway|
|S||Integer value which can be either read or written by the gateway. (to M-BUS writing is not possible)|
|X||Floating point value (with decimal place) which can/shall only be read by the gateway|
|Y||Floating point value (with decimal place) which can be either read or written by the gateway. (to M-BUS writing is not possible)|
|A||String, is used e.g. with BACnet Trends and ESPA4.4.4 data points|
Addresses are defined as follows:
Communication state with remote BACnet device: „<device> failure“
Whereas the following definition is valid:
|device||0 - 4194302|
0 - (2 22-2)
|Device-ID of the BACnet device.
If this ID matches the ID defined in bac1.cfg then it is a local data point (the gateway is BACnet server)
the data points are executed as server
Large Analog Value
Positiv Integer Value
|no||0 - 4194304|
(0 - 2 22)
|object number (must be unique within a device for each type|
For every local data points each point must be supplied with the so called required properties. Additionally to the required properties optional properties can be supplied.
Properties listed here cannot be written by other BACnet devices.
In case other BACnet devices shall write this property as well then the option ||W will declare it as writable.
The written values are valid until the gateway is rebooted. Using the option ||WP these values become persistent and will be stored on the gateway. They are still available even after a reboot of the gateway.
Entries for decription or units are defined as follows:
bac_description = description ||WP bac_units = 62 ||W
A „local“ at the Device Object Instance (DOI) means that the object is always executed as a server. The DOI is taken from the gateway settings. If the DOI is changed, the project planning does not have to be adapted. Below please find a description of local BACnet data point and their properties listed by type of data point:
Typical data point definitions for remote data points can be like this:
[M 1234.BI 5] name = digital operation message query = pe
[S 1234.BO 10] name = digital given value query = pe writecache = yes
[M 1234.MI 15] name = multistate message e.g. 0,1,2 for On, Off, Auto query = pe format = UINT16
[S 1234.MV 16] name = multistate given value e.g. step switch 0,1,2 for On, Off, Auto query = pe writecache = yes
[X 1234.AI 17] name = temperature value query = pe
[Y 1234.AO 17] name = temperature given value query = pe writecache = yes