QModbusServer on Raspberry Pi: Address is Protected

aniketRoxy

Hi,
I have created QModbusServer (TCP) in my application.
Following code is for create tcp modbus server.

const QUrl url = QUrl::fromUserInput("127.0.0.1:502");
modbusDevice->setConnectionParameter(QModbusDevice::NetworkAddressParameter, url.host());```
modbusDevice->setConnectionParameter(QModbusDevice::NetworkPortParameter, url.port());
modbusDevice->setServerAddress(1);

When I tried to run on raspberry pi, It shows an error.
Address is protected!!

jsulm

@aniketRoxy said in QModbusServer on Raspberry Pi: Address is Protected:

Address is protected!!

Use a port above 1024. Smaller port numbers require root privileges.

KroMignon

@aniketRoxy said in QModbusServer on Raspberry Pi: Address is Protected:

When I tried to run on raspberry pi, It shows an error.

On Linux system ports below 1024 are "privileged ports" and requires super user rights (root).

==> if you need to use port 502, you have to run as root.

aniketRoxy

Thank you @jsulm & @KroMignon !!
:)

Ports 0-1024 are "protected" for "known" services and By "protected", they must be used by system daemons. Thus, a regular user cannot start them.

Solution 1:
Run application using terminal:

sudo \path\to\app

Solution 2:
Use a port above 1024
So i changed port from 502 to 1502:

const QUrl url = QUrl::fromUserInput("127.0.0.1:1502");

Working now!!
<3 Qt