Adding a serial port as a USB adapter Linux Ubuntu, Debian, Raspbian
eHouse 1 Intelligent building | Smart House version RS-485 requires the installation of the RS-232/RS-485 converter which is an essential element to connect the “eHouse 1” system to PC , board computer , or another controller to become eHouse host (sever).
In case of computer with a built-in RS-232 port we can connect directly to it.
Otherwise, we will need the USB/RS-232C dongle, which enables you to connect converter RS-485 to the USB port.
In the case of PNP adapter is installed automatically as long as it is not some exotic brand is not supported by Linux.
When you turn the adapter into a USB port, make sure that it has been detected by the system command “dmesg” .
Then check command “lsusb” the drivers are known and are connected into the system mostly ttyUSB* and to which USB port.
Famous Brand adapters as Proliftic or Targus mostly do not require the installation of additional producer or other experimental drivers.
In the next part we can go to connect eHouse system and run the software eHouse4Linux, eHouse.PRO, eHouse4cServer or start programming the serial port service.
For further work we also need to change the permissions to the device for the safety of full rights “chmod 777 /dev/ttyUSB*”. Otherwise, you will receive an error “permision Denied” – lack of access on other user then root.
Particularly in the case of USB ->RS-232 may be a need to change the permissions on startup script or executing eHouse software. Disconnecting the adapter from the USB port will result in port removal and the addition after plug in with the default permissions .
After completion of the development work we can limit these rights to a minimum ensuring the proper operation of the system, however it is not critical issue.
Another issue is when we connect more then one USB to serial port dongle. At linux startup /dev/ttyUSB* can be switch depending witch device will be detest faster by linux. The best way is to check vendor code and/or producer name against port number.
For more information refer to post: Smart House eHouse Linux Programming