Serial Port Terminal transmitting at 300 baudrate
EDIT: I just noticed your "Do recommend other serial port terminal.", so to answer your question:


  Hexadecimal, just like I can do in Hercules, as it appears I can only send ascii characters alone. Is anyone familiar with TeraTerm? 


No.  



Just use H-Term. Its free and supports "all" baud
rates and input/output format can be ASCII, hex, binary and decimal.