INT 60 u - HP 95LX System Manager - RESET COMMUNICATIONS CHANNEL
        DI = 0E06h
        STACK:  2 WORDs unused dummies (for calls from high level languages)
                WORD    comm channel handle
                WORD    reset options
                        bit 0: reset line
                        bit 1: flush transmit buffer
                        bit 2: flush receive buffer
                        bit 3: reset modem
                        bit 4: reset receiver's S state
                        bit 5: reset transmitter's S state
Return: ???
        STACK unchanged