in reply to Win32::SerialPort faster connection than 115200 baud

You'll need to modify Win32::CommPort. It contains a table of what it believes are the valid values for baudrate:

COMMPROP=> [ qw( BAUD_USER BAUD_075 BAUD_110 BAUD_134_5 BAUD_150 BAUD_300 BAUD_600 BAUD_1200 BAUD_1800 BAUD_2400 BAUD_4800 BAUD_7200 BAUD_9600 BAUD_14400 BAUD_19200 BAUD_38400 BAUD_56K BAUD_57600 BAUD_115200 BAUD_128K

You'll need to add the value(s) that you are trying to set to prevent it from rejecting the attempts.

There is also a second table of baudrate-like values just below that may need updating also.

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