Category: <b>hardware</b>
<br>Flags: callout or callback (usually hooked rather than called)<p>
<pre><b>INT 74 - IRQ12 - POINTING DEVICE (PS)</b>

Notes:	may be masked by setting bit 4 on I/O port A1h
	DOS 3.3+ revectors IRQ12 to a stack-switching routine unless STACKS=0
	  has been set in CONFIG.SYS.  MS/PC-DOS use the IBM Interrupt Sharing
	  Protocol (see <a href=../../it/68/25.html>#02568</a>) when hooking this IRQ
	under DESQview, only the INT 15h vector and BASIC segment address (the
	  word at 0000h:0510h) may be assumed to be valid for the handler's
	  process
SeeAlso: INT 33/AX=0000h,INT 33/AX=0024h,INT 5C"NetBIOS",MEM 0040h:006Bh
</pre>