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/
	*200
START,	CLA
	TAD	M1
	JMS	MULP
M2,	-1
	HLT
	JMP	START
/
M1,	-1
/
/
/  MULP SUBROUTINE
/
/  RECEIVES MULTIPLICANDS AT CALL+1 AND IN AC
/
/  RETURNS ANSWER IN AC,,MQ  WITH LINK=0
/  RETURNS AT CALL+2
/
/  MECHANISM:  USES SHIFT AND ADD
/
/  HIGH PART OF ANSWER BUILT IN 'AC'
/  CONTROL BITS SHIFT RIGHT OUT OF 'MQ', WHILE ANSWER
/  BITS PROPOGATE DOWN INTO MQ
/
MULP,	0
	MQL		/CONTROL BITS IN MQ
	TAD	(-14	/CONTROL COUNT, 12 BITS
	DCA	MULC	/LOOP CAN'T QUIT EARLY ON ALL ZEROES
	CLL		/NASTY, THIS REAPPEARS  AS LINK UPON EXIT
LOOP,	SWP		/GET MQ TO SHIFT CONTROL BIT TO LINK
	RAR		/AND SHIFT IN ANSWER BIT TO TOP OF MQ
	SWP		/GET AC BACK
	SNL		/SKIP IF WE HAVE TO ADD IN MULTIPLICAND
	JMP	NOADD	/NO WE DON'T, JUST DO SHIFT
	CLL		/MUST CLEAR LINK TO REGISTER CARRY  FROM COMING
	TAD I	MULP	/ADDITION, GIVING 13 BIT RESULT
NOADD,	RAR		/LOW BIT A RESULT TO LINK
	ISZ	MULC	/DONE YET
	JMP	LOOP	/NO
	SWP		/FINAL ANSWER BIT TO MQ
	RAR		/CLEARING LINK FROM 'LOOP-1'
	SWP
	ISZ	MULP	/INCREMENT RETURN ADDR
	JMP I	MULP
/
MULC,	0
/
/
$