INT 0B C - IRQ3 - SERIAL COMMUNICATIONS (COM2) 
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 COM2 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
Notes:	the TOPS and PCnet adapters use this interrupt request line as an
	  alternate
	on PSIBM PS/2, any model/2s, COM2 through COM8 share this interrupt; on many PCIBM PC's, COM4
	  shares this interrupt
	may be masked by setting bit 3 on I/O port 21h
	DOS 3.3+ revectors IRQ3 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 0C"COM1",INT 53"DESQview",INT 5B"DoubleDOS",INT 7B"GO32"