IBM 5150 PC Technical Reference (6025005, August, 1981) (PDF)

LOC OBJ LINE SOURCE
F32B 06 3760 PUSH ES ESTABLISH ADDRESSING TO REGEN BUFFER
F3ZC IF 3761 pop OS FOR BOTH POINTERS
F32:0 SOFBOO 3762 CMP BL.O o SCROll MEANS BLANK FIELD
F330 C3 3763 RET ; RETURN WITH FUGS SET
3764 SCROLL_POSITION ENOP
3765
3766 j------ MOVE_ROW
F331 3767 HIO PROC NEAR
f331 SACA 3768 MOV Cl,Dl • GET • OF eOLS TO MOVE
F333 56 3769 PUSH 51
F334 57 3770 PUSH 01 I SAVE START ADDRESS
F33S F3 3171 REP MOVSW ; MOVE THAT LlUE ON SCREEN
F336 A5
F337 SF 3772 POP 01
F336 Sf 3773 POP 51 I RECOVER ADDRESSES
F339 C3 3774 RET
3775 HID ENDP
3776
3777 j------ CLEAR_ROW
F33A 3778 HII PROC NEAR
F33A SACA 3779 MOV Cl.Dl I GET I CCUJMNS TO CLEAR
F33C 57 3780 PUSH 01
F33D F3 3781 REP STQSW I STORE THE fILL CHARACTER
F33E AS
F33f SF 3782 pop 01
F340 C3 3783 RET
3784 Nil ENDP
3765 ;--------------------------­ ---­ ---­
3766 ; SCROLL_DOWN
3787 THIS ROUTINE MOVES THE CHARACTERS WITHIN A DEFINED
3788 BLOCK DOWN ON THE SCREEN, FILLING THE TOP LINES
3789 WITH A DEFINED CHARACTER
3790 ; INPUT
3791 (AH I = CURRENT CRT MODE
3792 (All = NUMBER OF LINES TO SCROLL
3793 (CX I = UPPER LEFT CaRtIER OF REGION
3794 (OX) = LOWER RIGHT CORNER OF REGION
3795 (BHJ = FILL CHARACTER
3796 (OS I = DATA SEGMENT
3791 'ESJ = REGEN SEGMENT
3798 ;OUPUT
3799 NOHE -­ SCREEN IS SCROllED
3800 ; --­ ---­ ----­ ------------------------­
F341 3801 SCROLL_DO~N FROC NEAR
f341 FD 1802 STD ; DIRECTION FOR SCROLL DOWN
f342 8AD8 3803 NOV BL,AL ; LINE COUtIT TO BL
F344 80FC04 3804 CMP AH,4 ; TEST FOR GRAPHICS
F347 7208 3805 JC HI2
F349 80FC01 3806 CNP AH,7 i TEST FOR BW CARD
F34C 7403 3S07 JE HI2
F34E E9A601 3808 JMP GRAPHICS_DOWN
F351 1809 NI2.: ; CONTINUE_DOWN
F351 53 3810 FUSH BX ; SAVE ATTRIBUTE IN 8H
F352 8BCZ 3811 NOV AX,OX ; LOWER RIGHT CORNER
F354 E893FF 3812. CALL SCROll.POSITION ; GET REGEN LOCATION
F357 742.0 3811 JZ HI.
F3S9 2BfD 3814 SUB SI,AX ; SI IS FROM ADDRESS
f358 8AE6 3815 MOV AH,OH ; GET TOTAL II ROWS
F35D un 3816 SUB AH,Bl ; COUNT TO MOVE IN SCROLL
F35F 3817 N13:
F3SF E8CFFF 3816 CALL NID ; MOVE ONE ROW
F362 2.BF5 3819 SUB SI,ep
F364 2BFD 3820 SUB DI,BP
F366 fEce 3821 DEC AH
F368 75F5 3622 J~lZ HI3
F36A 3823 N14:
F36A 58 3824 POP AX t RECOVER ATTRIBUTE IN AH
F368 B020 3825 MOV AL, •
F36D 3826 N15:
F36D ESCAFF 3827 CAlL HII ; CLEAR ONE ROW
F370 2BFa 3828 SUB aI,BP ; GO TO NEXT ROW
F372 FEee 3829 DEC 8L
F374 75F7 3830 JNZ HIS
F376 E957FF 3831 JMP HS ; SCROll.END
F379 3832 N16:
F379 8ADE 3833 HOY BL,DH
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