INT 14 - I1541 - SEND LISTEN SIGNAL                                             
	AX = 4004h
	BH = device number (0..15)
Return: CF clear if successful
	CF set on error
	    AL = error number (see #00354)
SeeAlso: AX=4005h,AX=4006h


(Table 00354)
Values for I1541 error number:
 00h	device not present
 01h	listener not ready
 02h	missing EOI(End of Interrupt) A particular command sent to the interrupt controller to indicate that the interrupt has been handled by software and that new interrupts of the same or lower priority may now be signalled by the interrupt controller. time-out
 03h	EOI(End of Interrupt) A particular command sent to the interrupt controller to indicate that the interrupt has been handled by software and that new interrupts of the same or lower priority may now be signalled by the interrupt controller. not completed
 04h	data not released
 05h	frame error