knx-go
This repository contains a collection of Go packages that provide the means to communicate with KNX networks.
Packages
| Package | Description |
|---|---|
| knx | Abstractions to communicate with KNXnet/IP servers |
| knx/knxnet | KNXnet/IP protocol services |
| knx/dpt | Datapoint types |
| knx/cemi | CEMI-encoded frames |
| cmd/knxbridge | Tool to bridge KNX networks between a KNXnet/IP router and gateway |
Installation
Simply run the following command.
$ go get -u github.com/vapourismo/knx-go/...
Examples
KNXnet/IP Group Client
If you simply want to send and receive group communication, the GroupTunnel or GroupRouter might be sufficient to you.
package main
import (
"log"
"os"
"github.com/vapourismo/knx-go/knx"
"github.com/vapourismo/knx-go/knx/cemi"
"github.com/vapourismo/knx-go/knx/dpt"
"github.com/vapourismo/knx-go/knx/util"
)
func main() {
// Setup logger for auxiliary logging. This enables us to see log messages from internal
// routines.
util.Logger = log.New(os.Stdout, "", log.LstdFlags)
// Connect to the gateway.
client, err := knx.NewGroupTunnel("10.0.0.7:3671", knx.DefaultTunnelConfig)
if err != nil {
log.Fatal(err)
}
// Close upon exiting. Even if the gateway closes the connection, we still have to clean up.
defer client.Close()
// Send 20.5°C to group 1/2/3.
err = client.Send(knx.GroupEvent{
Command: knx.GroupWrite,
Destination: cemi.NewGroupAddr3(1, 2, 3),
Data: dpt.DPT_9001(20.5).Pack(),
})
if err != nil {
log.Fatal(err)
}
// Receive messages from the gateway. The inbound channel is closed with the connection.
for msg := range client.Inbound() {
var temp dpt.DPT_9001
err := temp.Unpack(msg.Data)
if err != nil {
continue
}
util.Logger.Printf("%+v: %v", msg, temp)
}
}In case you want to access a KNXnet/IP router instead of a gateway, simply replace
client, err := knx.NewGroupTunnel("10.0.0.7:3671", knx.DefaultTunnelConfig)with
client, err := knx.NewGroupRouter("224.0.23.12:3671", knx.DefaultRouterConfig)KNXnet/IP CEMI Client
Use Tunnel or Router for finer control over the communication with a gateway or router.
KNX Bridge
The knxbridge tool (in package cmd/knxbridge) has multiple use cases.
Expose a KNX network behind a gateway at 10.0.0.2:3671 on the multicast group 224.0.23.12:3671.
This allows routers and router clients to access the network.
$ knxbridge 10.0.0.2:3671 224.0.23.12:3671
Connect two KNX networks through gateways. In this example one gateway is at 10.0.0.2:3671, the
other is at 10.0.0.3:3671.
$ knxbridge 10.0.0.2:3671 10.0.0.3:3671
Discover all KNXnet/IP Servers
The following example shows how to discover all routers/gateways on a network.
package main
import (
"log"
"os"
"time"
"github.com/kr/pretty"
"github.com/vapourismo/knx-go/knx"
"github.com/vapourismo/knx-go/knx/util"
)
func main() {
// Setup logger for auxiliary logging. This enables us to see log messages from internal
// routines.
util.Logger = log.New(os.Stdout, "", log.LstdFlags)
servers, err := knx.Discover("224.0.23.12:3671", time.Millisecond*750)
if err != nil {
log.Fatal(err)
}
util.Logger.Printf("%# v", pretty.Formatter(servers))
}Describe a Single KNXnet/IP Server
The following example shows how to get a description from a single server.
package main
import (
"log"
"os"
"time"
"github.com/kr/pretty"
"github.com/vapourismo/knx-go/knx"
"github.com/vapourismo/knx-go/knx/util"
)
func main() {
util.Logger = log.New(os.Stdout, "", log.LstdFlags)
// Describe KNXnet/IP server at given address and default port
servers, err := knx.DescribeTunnel("192.168.1.254:3671", time.Millisecond*750)
if err != nil {
log.Fatal(err)
}
util.Logger.Printf("%# v", pretty.Formatter(servers))
}