Case 2 - one button mapped to one LED¶

Having Thread network configured and operational, you can start KNX IoT device configuration and testing. One device must be configured as an Actuator and one as a Sensor.

Perform configuration/mapping of buttons built in to KNX IoT Sensor nRF52840 DK to control LEDs built in to the KNX IoT Actuator nRF52840 DK - one button to one LED. It is achieved by dedicated on KNX group to every input-output pair.

Configure the Actuator device by adding entries to Actuator’s Group Object Table.

uart:~$ knx got add 1 /p/1 22 [1]
uart:~$ knx got add 2 /p/2 22 [2]
uart:~$ knx got add 3 /p/3 22 [3]
uart:~$ knx got add 4 /p/4 22 [4]

Set device installation identifier and device individual address for Actuator device.
```
uart:~$ knx dev iid 1
uart:~$ knx dev ia 1
```

Configure the Sensor device by adding entries to Sensor’s Group Object Table.

uart:~$ knx got add 1 /p/1 22 [1]
uart:~$ knx got add 2 /p/2 22 [2]
uart:~$ knx got add 3 /p/3 22 [3]
uart:~$ knx got add 4 /p/4 22 [4]

Set device installation identifier and device individual address for Sensor device.
```
uart:~$ knx dev iid 1
uart:~$ knx dev ia 2
```
Devices are configured. Use one of the sensor’s buttons to control one of the assigned actuator’s LEDs. The interconnections between buttons and LEDs are presented in the following table:

Control button (Sensor)

Controlled LED (Actuator)

BUTTON1

LED1

BUTTON2

LED2

BUTTON3

LED3

BUTTON4

LED4

Control button (Sensor)	Controlled LED (Actuator)
BUTTON1	LED1
BUTTON2	LED2
BUTTON3	LED3
BUTTON4	LED4