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15BC

Category: vendor-specific BIOS extensions

INT 15 - Phoenix 386 BIOS - DETERMINE CPU SPEED FOR DELAY LOOPS

	AH = BCh
Return: CF clear
	(Phoenix 1.10 10a) BYTE 0040h:00B0h set to delay loop count
	(Dell 4xxDE BIOS A11) WORD 0040h:00ECh set to delay loop count
Note:	this function reads system timer channel 0 twice, then does
	  calculations on the returned values to determine the delay loop
	  counter needed by the BIOS for beeps and floppy timeouts
SeeAlso: AX=2305h,MEM 0040h:00B0h

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