AMD Am186 Series, Instruction Set

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Instruction Set 4-176
POP POP
Examples
This example copies a string of 16-bit integers in one segment of memory to a string in
another segment. The words are copied, one by one, from last to first.
; defined in SEG_A
STRING1 DW -30000,10250,31450,21540,-16180
S1_LENGTH EQU 5
; defined in SEG_B
STRING2 DW S1_LENGTH DUP (?)
S2_END_ADDR DD S SIZE STRING2 - TYPE STRING2
; notify assembler: DS and ES specify
; different segments of memory
ASSUME DS:SEG_A, ES:SEG_B
; set up segment registers with different segments
MOV AX,SEG_A ; load one segment into DS
MOV DS,AX ; DS points to SEG_A
MOV AX,SEG_B ; load another segment into ES
MOV ES,AX ; ES points to SEG_B
; copy string in segment A to string in segment B
; save ES
PUSH ES
; set up registers and flags
LEA SI,STRING1 ; load source offset (segment = DS)
; load dest. segment into ES and offset into DI
LES DI,ES:S2_END_ADDR
MOV CX,S1_LENGTH ; set up counter
STD ; process string high to low
; copy source string to destination
REP MOVSW
; restore saved ES
POP ES