# Need help with capabilities -\> listner
**URL:** https://community.homey.app/t/need-help-with-capabilities-listner/124783
**Category:** Developers
**Created:** [December 20, 2024, 11:44am UTC](https://community.homey.app/t/need-help-with-capabilities-listner/124783 "2024-12-20T11:44:46Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@H\_van\_Barneveld](https://community.homey.app/u/H_van_Barneveld)
#### Post date: [December 20, 2024, 11:44am UTC](https://community.homey.app/t/need-help-with-capabilities-listner/124783/1 "2024-12-20T11:44:46Z")
hello,
i really want to connect our heatpump to homey. Therefor i start my own ‘development’ . what means i try to learn and copy from other existing apps/integrations.
Today i can connect the modbus IP interface, i can read differrent registers. also i add to different capabilities. ( picker to set mode & thermostat to adjust settings.) but from this point i miss the examples, knoledge how to proceed.
the picker i can set another mode but i do not know how to ensure the picker gets the active value from the modbusregister. when i open the device the picker doesn’t show the active setting. are there examples available to find out how to configure this?
The same question for the thermostat. for this i also am looking for code that belongs to this UI (capabilitylister ) i guess.
Can somebody help me to proceed ?
Kind regards,
Henk
---
### Author:  [@Rmb](https://community.homey.app/u/Rmb)
#### Post date: [December 20, 2024, 12:09pm UTC](https://community.homey.app/t/need-help-with-capabilities-listner/124783/2 "2024-12-20T12:09:15Z")
I just use the Modbus app and Advanced Virtual Device to display (and set) values. Works OK for me.
---
### Author:  [@Adrian\_Rockall](https://community.homey.app/u/Adrian_Rockall)
#### Post date: [December 20, 2024, 5:20pm UTC](https://community.homey.app/t/need-help-with-capabilities-listner/124783/3 "2024-12-20T17:20:05Z")
You will need to poll the registers to fetch the values and set them on the capability using setCapabilityValue(‘name\_of\_capability’, value).
You could use a timer to poll registers, e.g. homey.setInterval or homey.setTimeout.
---
### Author:  [@H\_van\_Barneveld](https://community.homey.app/u/H_van_Barneveld)
#### Post date: [December 22, 2024, 4:17pm UTC](https://community.homey.app/t/need-help-with-capabilities-listner/124783/4 "2024-12-22T16:17:36Z")
Hello Adrian, or anyone els,
I have working all weekend to get it work and making some progress. however iám still struggling. i created an lister that registrate all changes. after using the picker i see the new vallue in the log. when i tried to write this new value to the right register it is not accepted. When using a modbus testtool i’am able to read and set the value by using FC 3 or FC 6.
I’am using code like below. do you have any idea how to solve this.
// Register capability listener for Operation\_mode
this.registerCapabilityListener(‘Operation\_mode’, async (value) =\> {
this.log(‘Changes to :’, value);
this.log(‘Modbus register to write to is:’, OPERATION\_MODE\_ADDRESS);
```
// Voeg een controle toe om te bevestigen dat de waarde geldig is
// Lees de huidige waarde van het holding register
try {
const currentRegister = await this._client.readHoldingRegisters(OPERATION_MODE_ADDRESS, 1);
const currentValue = currentRegister.response._body.valuesAsBuffer.readUInt16BE(0);
this.log(`Current value in register ${OPERATION_MODE_ADDRESS} is: ${currentValue}`);
} catch (error) {
this.error(`Error reading current value from operation mode register: ${error.message}`);
return;
}
// Voeg een vertraging van 2 seconden toe
await this.delay(2000);
this.log('delay2000ms');
// Log de waarde en het adres die worden geschreven
this.log(`Writing value ${value} to operation mode register at address ${OPERATION_MODE_ADDRESS}`);
// Schrijf de nieuwe waarde naar het Modbus-register
try {
const result = await this._client.writeSingleRegister(OPERATION_MODE_ADDRESS, value);
this.log(`Written value ${value} to operation mode register ${OPERATION_MODE_ADDRESS}`, result);
} catch (error) {
this.error(`Error writing to operation mode register: ${error.message}`);
}
});
```
}
---
### Author:  [@H\_van\_Barneveld](https://community.homey.app/u/H_van_Barneveld)
#### Post date: [December 22, 2024, 8:41pm UTC](https://community.homey.app/t/need-help-with-capabilities-listner/124783/5 "2024-12-22T20:41:17Z")
Solved