Hi,

I want to be able to change the baud rate of the COM port dynamically in runtime.
Anyone know how to achieve it?

Hi.
You can use method of Modbus Master: UpdateComParameters.

Keep in mind that you will need to call this method every time the controller is loaded, because when the runtime starts, the values will be overwritten by those set in the project tree.

Hi E.Kislov,

I had already tried this method, which is called during every PLC cycle but it doesn't seem to affect/change the COM port settings.
Maybe there is something else that needs to be done first.

eSmart07_RTU.UpdateComParameters(
udiBaudrate:= BaudRate,
usiMedium:= 1,
usiParity:= 2,
usiDataBits:= 8,
usiStopBits:= 1,
xPolarization:= FALSE,
COMPORT:= 1);

BTW you make great Codesys videos on YT.

I think you should use it this way:

eSmart07_RTU.xStop := TRUE;
eSmart07_RTU.Enable := FALSE; // maybe not necessary
eSmart07_RTU.UpdateComParameters(...);
eSmart07_RTU.Enable := TRUE; // maybe not necessary
eSmart07_RTU.xStop := FALSE;

Before using Enable property you should: Device - Plc Settings - Activate diagnostics for devices

Perhaps, Enable is not necessary, and xStop will be enough...

And thanks for the compliment, it's very encouraging.

Unfortunately it doesn't work.

I want to read the current COM settings so I found the SysComGetSettings function in the SysCom library.

"SysComGetSettings = Get the parameter of the interface specified by handle."

But how do I set the hComPort RTS_IEC_HANDLE to the serial port COM1?

rtsResult            : RTS_IEC_RESULT;
stComPortSettings    : SysCom.ComSettings;
hComPort             : RTS_IEC_HANDLE;

**hComPort := ????**
rtsResult := SysComGetSettings(hCom:= hComPort, pSettings:= ADR(stComPortSettings), pSettingsEx:= 0);