Atari 400 Technical Reference Manual page 371

ERR LINE ADDR Bl B2 B3 B4
DISPLAY HANDLER -- 10-30-78 -- DISPLC
PAGE 110
4893
FA23
FO 04
BEG DOCR1A
; (INSCHR SPECIAL CASE)
4894 FA25 18
CLC
; INSERT "0" INTO BIT MAP
4895
FA26 20 A5 F8 JSR
INSLIA
4896 FA29 4C DO FB
DOCR1A: JMP DOLCOL
iCONVERT ROW AND-COL TO LOGCOL AND RETURN
4897 FA2C A9 00
NOSCRL: LOA #0
iDOCR
WITHOUT SCROLL
4898 FA2E FO 02
BEG NOSCRl
i
(UNCONDITIONAL)
4899 FA30 A9 9B
DOCRWS: LDA
#$9B iDOCR WITH SCROLLING (NORMAL MODE)
4900 FA32 85 70 NOSCR1: STA
INSDAT
4901
FA34 20 E4 FC DOCR: JSR COLCR
iPLACE COLCRS AT LEFT EDGE
4902 FA37 A9 00
LOA #0
4903
FA39
85 56
STA
COLCRS+l
4904 FA3B E6 54
INC ROWCRS
4905 FA3D A6 57
DOCR2: LDX DINDEX
4906 FA3F AO 18 LOY
#24 iSET UP SCROLL LOOP COUNTER
4907
FA41
24 7B
BIT SWPFLG
4908
FA43 10 05 BPL
DOCR2A iBRANCH IF NORMAL
4909 FA45 AO 04
LOY
#4
4910 FA47 98
TYA
4911 FA48 DO 03
BNE DOCR2B
i
(UNCONDITIONAL)
4912 FA4A BD 99 FE
DOCR2A: LOA
NOROWS,X iGET NO OF ROWS
4913 FA4D C5 54
DOCR2B: CMP ROWCRS
4914 FA4F DO 26
BNE INCRS1
4915
FA51 8C 90 02 STY HOLD3
4916
FA54
8A
TXA
iDON'T SCROLL IF MODE
<>
0
4917 FA55 DO 20
BNE INCRSl
4918 FA57 A5 70 LOA
INSDAT
iOR IF INSDAT = 0
4919
FA59
FO 1C
BEG INCRSl
4920
LDA INSDAT
IF INSDAT <> $9B THEN ROLL IN A 0
4921 FA5B C9 98
CMP #$98
iTO EXTEND BOTTOM LOGICAL LINE
4922 FA5D 38
SEC
4923 FA5E FO 01
BEG DOCR4B
4924
FA60
18
CLC
4925 FA61 20 AC FB
DOCR4B: .JSR SCROLL
iLOOP BACK TO HERE IF >1 SCROLLS
4926 FA64 EE B8 02
INC SCRFLG
4927 FA67 C6 6C DEC
BUFSTR iROWS MOVE UP SO BUFSTR SHOULD TOO
4928
FA69 CE 9D 02 DEC HOLD3
4929 FA6C AD B2 02
LDA LOGMAP
4930 FA6F 38
SEC
iFOR PARTIAL LINES, ROLL IN A 11111
4931 FA70 10 EF BPL
DOCR4B iAGAIN IF PARTIAL LOGICAL LINE
4932 FA72 AD 9D 02 LDA
HOLD3 iPLACE CURSOR AT NEW LINE NEAR THE BOTTOM
4933 FA75 85 54
STA ROWCRS
4934 FA77 4C DD FB
INCRS1 : .JMP DOLCOL
iCOLVERT ROW AND COL TO LOGCOL AND RETURN
4935
4936
4937
i SUBEND: SUBTRACT ENDPT FROM ROWAC OR COLAC.
(X=O OR 2)
4938
4939
FA7A 38 SUBEND: SEC
4940 FA7B B5 70
LDA ROWAC, X
4941 FA7D E5 74 SBC
ENDPT
4942 FA7F 95 70
STA ROWAC,X
4943 FA81 B5 71
LDA ROWAC+l,X
4944 FA83 E5 75
SBC ENDPT+1
4945 FA85 95 71 STA
ROWAC+l, X
4946 FA87 60
RTS