INT 77 C - IRQ15 - RESERVED (ATIBM PC AT,PSIBM PS/2, any model)
Notes:	may be masked by setting bit 7 on I/O port A1h
	DOS 3.3+ revectors IRQ15 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 5F"IRQ15",MEM 0040h:006Bh
                                                                                

INT 77 C - IRQ15 - SECONDARY IDE(Integrated Drive Electronics) A type of disk drive interface which essentially extends the PCIBM PC's expansion bus all the way to the drive and places the drive controller on the disk drive itself.	 See also ESDI. CONTROLLER - OPERATION COMPLETE
Notes:	may be masked by setting bit 7 on I/O port A1h
	DOS 3.3+ revectors IRQ15 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 5F"IRQ15",MEM 0040h:006Bh
                                                                                

INT 77 C - IRQ15 - POWER CONSERVATION (Compaq SLT/286)
Note:	may be masked by setting bit 7 on I/O port A1h
SeeAlso: INT 15/AX=4600h,INT 5F"IRQ15"