INT 14h, 00h    Initialize USART
 INT 14h, 01h    Transmit character
 INT 14h, 02h    Receive character
 INT 14h, 03h    Get USART status
 INT 14h, 04h    Extended initialize                                     (PS)
 INT 14h, 05h    Extended communication port control                     (PS)


 INT 14h, 00h    FOSSIL (Fido/Opus/Seadog Standard Interface Level) - INITIALIZE
 INT 14h, 02h    FOSSIL - receive character with wait
 INT 14h, 04h    FOSSIL - initialize driver
 INT 14h, 05h    FOSSIL - Deinitialize driver
 INT 14h, 06h    FOSSIL - Raise/lower dtr
 INT 14h, 07h    FOSSIL - Return timer tick parameters
 INT 14h, 08h    FOSSIL - Flush output buffer waiting till all output is done
 INT 14h, 09h    FOSSIL - Purge output buffer throwing away all pending output
 INT 14h, 0Ah    FOSSIL - Purge intput buffer throwing away all pending input
 INT 14h, 0Bh    FOSSIL - Transmit no wait
 INT 14h, 0Ch    FOSSIL - NON-DESTRUCTIVE Read ahead
 INT 14h, 0Dh    FOSSIL - Keyboard read without wait
 INT 14h, 0Eh    FOSSIL - Keyboard read with wait
 INT 14h, 0Fh    FOSSIL - Enable/disable flow control
 INT 14h, 10h    FOSSIL - Extended  k checking and transmit on/off
 INT 14h, 11h    FOSSIL - Set current cursor location
 INT 14h, 12h    FOSSIL - Read current cursor location
 INT 14h, 13h    FOSSIL - Single character ansi write to screen
 INT 14h, 14h    FOSSIL - Enable or disable watchdog processing
 INT 14h, 15h    FOSSIL - Write character to screen using bios support routines
 INT 14h, 16h    FOSSIL - Insert/delete function from timer tick chain
 INT 14h, 17h    FOSSIL - Reboot system
 INT 14h, 18h    FOSSIL - Read block
 INT 14h, 19h    FOSSIL - Write block
 INT 14h, 1Ah    FOSSIL - Break begin or end
 INT 14h, 1Bh    FOSSIL - Return information about the driver
 INT 14h, 7Eh    FOSSIL - Install an external application function
 INT 14h, 7Fh    FOSSIL - Remove an external application function