Configure your connection

Most configuration mistakes come from mixing settings that sound similar but act at different layers. Configure the local program, the remote target, and the BACnet network identity separately.

BACnet/IP settings

Purpose	CLI	Python	Meaning
Local interface selection	--interface	interface	Local interface/bind input; not a remote device address
Local UDP port	--port	port	The port used by this local client
Discovery broadcast destination	--broadcast	broadcast_address	Where broadcast discovery is directed
APDU timeout	--timeout	apdu_timeout_ms	Request timeout in milliseconds
Remote endpoint	Command target	Method address	Target address and, where needed, remote port

The reviewed CLI defaults to local UDP port 47808, broadcast address 255.255.255.255, and APDU timeout 6000 ms. One-shot commands without an interface use 0.0.0.0; the interactive shell may prompt for an interface.

Do not infer receive isolation or multi-interface behavior from the word “bind.” Broadcast reception can involve wildcard socket behavior. Verify the actual host/interface arrangement, especially when multiple network adapters, VPNs, or local BACnet applications are present.

A remote port is not a local port

bacnet --port 47810 read 192.168.1.100:47809 ai:1 pv

This example chooses local port 47810 and remote port 47809. It is a directed-read illustration, not a prescription for changing the ports used by an operational BACnet network.

For standard same-subnet discovery, start with the intended BACnet network’s port and address plan. Changing the local port just to avoid a conflict can change discovery and response behavior; first identify the competing process.

Configuration lives in the interface you use

The reviewed CLI exposes command-line options and interactive session settings. These guides do not invent a global bacnet.toml, a --config flag, or a universal environment-variable layer.

In Python, construct the client or server with the documented keyword arguments. In Rust, configure the corresponding builder and transport. An application’s own JSON/TOML configuration can map to those APIs, but that is an application convention—not a built-in CLI contract.

Keep units visible

Use --timeout 6000 for a 6000-millisecond APDU timeout. Discovery’s --wait and foreign-device registration’s --ttl are measured in seconds. MS/TP baud is a line rate, and BACnet/SC heartbeat fields have their own documented units and bounds.

Do not copy a numeric value between settings merely because the names resemble one another.

Network-specific prerequisites

On multiple subnets, review BACnet routing and authorized BBMD/foreign-device arrangements; broad UDP port forwarding is not a substitute for a documented topology. In containers or virtual machines, a working unicast read does not prove broadcast reception. For BACnet/SC, follow certificate and identity setup. For a serial trunk, follow MS/TP commissioning.

Keep configuration out of published evidence

Documentation, GitHub Pages, public issues, and screenshots must not contain real private keys, credentials, unredacted building addresses, or customer network captures. Use representative examples and privately retained operational records.

Sources and release scope

These instructions target v0.11.0. Source review is not a claim of hardware qualification.

CLI definitions · CLI transport construction · Python constructor.