GE Carescape B450 not work on Raspberry Pi Vital Recorder #719

Hello,
I am trying to use Vital Recorder with a GE Carescape B450 monitor on a Raspberry Pi 5 via an FTDI USB-RS232 adapter. Also I have tried with PL2303 adapter, but the result war similar.

• On Windows, Vital Recorder connects successfully and starts receiving data from the B450.

• On Raspberry Pi (Linux), When I run the executable file I installed from your release version,  it repeatedly tried to open the monitor, but always failed. Then I first checked the connection of the port and then try to use sudo cat to read the data from the port. Vital Recorder detects the serial port but never receives any data from the monitor.

So I thought maybe the monitor exepected to recevive something before the streaming began. So I wanted to find out why the windows version worked, so I investigated further with Wireshark on Windows:

• Vital Recorder sends two initialization frames (0x7E … 0x7E) right after opening the port.

• Only after these frames does the B450 begin continuous data streaming.

I don't if these functions are also contained in the Raspberry Pi version. Therefore, I would like to ask:

• Could it be that the Linux build of Vital Recorder does not fully implement the RS232 initialization for GE monitors (RTS/CTS, DTR, or the init packet sequence)?

• Is there a workaround, or can this handshake be added to the Linux version? 

Thank you for your help.