About this task
For information on peer-to-peer communication and configuration guidelines, see the Peer-to-Peer Communication section. You must configure peer-to-peer communication in the Configuration mode.
To set up peer-to-peer communication:
Identify and record the Instance Number (BACnet ID) of the device to which you want to communicate. You can locate this attribute on the Network Settings screen of the Hardware Definition Wizard.
Note: You also can locate the Instance Number of devices using the Metasys Site Management Portal UI. This method allows you to look up multiple device instance numbers at once.If you used the Johnson Controls Point Schedule to transfer to the controllers, check the instance number on the MSTP Field Device tab of the project’s Point Schedule.
Identify and record the Object Identifier of the object in which you want to read/write a value. You can locate this attribute in the Details dialog box.
Note: The Object Identifier consists of the BACnet Class ID and the object’s Instance Number separated by a colon. For example, an Object Identifier of AV:10026 has a BACnet Class ID of AV and an Instance Number of 10026.
- View the details of the desired Network Input or Network Output.
- Click Edit.
In the configuration table for the Peer Reference attribute, modify the elements as follows:
- Instance Number (BACnet ID): Enter the device’s Instance Number in the field as recorded in Step 1.
Object Identifier: Select the BACnet Class ID from the drop-down menu and enter the object’s Instance Number in the field as recorded in Step 2.
The BACnet Class ID should typically have the same Data Type as the object for which the peer-to-peer attribute is being configured (for example, an AV Network Input should reference another AV, an AI, or an AO object). If multistate values are used in peer-to-peer references, the Enumeration sets should be the same. If the sets do not match, you must determine if the values in the sets are compatible.
Click Apply and then click Close.
Note: Check the Error Status attribute to diagnose communication problems. This attribute displays the status of the last communication that occurred with an input or output reference.
Common errors include:
- Surrogate Object is Not Bound: The referenced device (Device ID) has never responded because a device with the entered Device ID either does not exist or is offline.
- Remote Device is Offline: The referenced device did respond at one time but is no longer responding.
- Unknown Object: The referenced device exists and is online, but the Object ID that was entered does not exist on that device.
- Type Mismatch: The referenced object exists but the data type of the referenced attribute/property is invalid. This error generally does not appear for inputs on Johnson Controls or third-party devices. For outputs on third-party devices, the Object Type of the output needs to match the type of output object making the peer reference.
- Unknown Property: This error generally does not appear if you leave the Peer Reference Attribute field as Present Value. If you change this setting, the Unknown Property error means the referenced object exists but the referenced attribute does not exist.