INT 0C C - IRQ4 - SERIAL COMMUNICATIONS (COM1) 
Desc:	automatically asserted by the UART(Universal Asyncronous Receiver/Transmitter)  A peripheral device which converts a sequence of bytes into a serial bit stream at a programmable rate, and vice versa.  This device is what makes an RS-232 serial port function.  See also USART. when COM1 needs attention, if the
	  UART(Universal Asyncronous Receiver/Transmitter)  A peripheral device which converts a sequence of bytes into a serial bit stream at a programmable rate, and vice versa.  This device is what makes an RS-232 serial port function.  See also USART. has been programmed to generate interrupts
BUG:	this vector is modified but not restored by Direct Access v4.0, and
	  may be left dangling by other programs written with the same version
	  of compiled BASIC(Beginner's All-purpose Symbolic Instruction Code) A programming language originally designed as a means of teaching FORTRAN.  There are many variations of BASIC with differing capabilities; the majority are interpreted but compiled BASIC is becoming more popular.	All genuine IBMInternational Busiuness Machines personal computers (including the latest PS/2IBM PS/2, any model models) come equipped with a cassette-based BASIC interpreter in ROM.
Notes:	on many PCIBM PC's, COM3 shares this interrupt
	may be masked by setting bit 4 on I/O port 21h
	DOS 3.3+ revectors IRQ4 to a stack-switching routine unless STACKS=0
	  has been set in CONFIG.SYS.  MS/PC-DOS use the IBMInternational Busiuness MachinesInternational Busiuness Machines) A hardware, software and other service technology company founded in 1911. Interrupt Sharing
	  Protocol (see #02568) when hooking this IRQ(Interrupt ReQuest) A hardware line connected to the interrupt controller chip which signals that a CPU interrupt should be generated.
SeeAlso: INT 0B"COM2",INT 54"DESQview",INT 5C"DoubleDOS",INT 7C"GO32"