This code should only have 3 possible outcomes as far as what it prints to screen:

"Reading.....Success" periods for each timeout until int13 gives no error
"Reading.....Failure" periods for each timeout until an error other than timeout is given
"Reading............" infinite loop of printing periods because of infinite timeouts

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read:
		mov $reading_message,%si	#prints "Reading" message
		call putstr

read.retry:
		mov $read_retry,%si		#prints a '.' for each read attempt
		call putstr

		mov $0x42,%ah
		mov drive,%dl
		mov $edd_packet,%si
		int $0x13			#all registers are set and, extended read call
						#is executed

		jc read.fail			#if read had no error then
						#print "Success" and return to caller
						#if error then jump to read.fail

		mov $reading_done,%si
		call putstr
		ret

read.fail:
		cmp $0x80,%ah			#if error was read timeout start another attempt
		je read.retry
		mov $unknown_fail,%si		#for any other error just
						#print 'Failure'
						#and give up
		call putstr

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edd_packet: 	.byte 0x10 			# Length
		.byte 0			 	# Reserved
edd_len: 	.byte 0x0 			# Num to read
 		.byte 0 			# Reserved
edd_addr: 	.word 0x0,0x0 			# Seg:Off
edd_lba: 	.quad 0x00 			# LBA

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