Intel 210200-002 manual Add two unpacked BCD Ascii strings together

ARCHITECTURE AND INSTRUCTIONS

Sample Two:

Add two unpacked BCD (ASCII) strings together.

MY_DATA SEGMENT

STRING_1 DB

STRING_2 DB

MY_DATA ENDS

MY_CODE SEGMENT ASSUME

GO:MOV MOV MOV CLC CLD MOV MOV MOV JCXZ

CYCLE:LODS

ADC

AAA

STOS

LOOP

FINISH:HLT

MY-CODE ENDS END

'1','7','5','2'	;value is 2571
'3','8','1','4'	;value is 4183
CS:MY-CODE, DS:MY-DATA
AX,MY-DATA	;establish data segment
DS,AX
ES,AX
	;no carry initially
SI,OFFSET STRING_1	;forward strings
	;establish string pointers
DI,OFFSET STRING_2
CX,LENGTH STRING_1
FINISH
STRING_1	;get STRING_1 element
AL,[DI]	;add STRING_2 element
	;correct for ASCII
STRING_2	;result into STRING_2
CYCLE	;repeat for entire element
GO

Sample Three:

Decimal multiplication algorithm.

MY_DATA	SEGMENT
A	DB	'3','7','5','4','9'
B	DB	'6'
C	DB	LENGTH (A) DUP (7)
MY_DATA	ENDS
MY_CODE	SEGMENT
	ASSUME	CS:MY _CODE,DS:MY _DATA
GO:	MOV	AX, MY_DATA
	MOV	ES,AX
	CLD
	MOV	SI,OFFSET A
	MOV	DI,OFFSET C
	MOV	CX,LENGTH A
	AND	B,OFH
	MOV	BYTE PTR [SI].O
	JCXZ	FINISH
CYCLE:	LODS	A
	AND	AL,OFH
	MUL	AL,B
	AAM
	ADD	AL,[DI]
	AAA
	STOS	C
	MOV	[DI].AH
FINISH:	LOOP	CYCLE
	HLT
MY-CODE	ENDS
	END	GO

;establish data segment

;forward strings ;establish pointers

;establish count ;clear upper half of b ;clear c[l]

;get ali]

;clear its high-order bits ;multiply by b ;correct for ASCII

;add to c[i] ;adjust for ASCII ;store in c[i]

;,..and c[l]

;repeat for entire string

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