Atari 400 Technical Reference Manual page 375

ERR LINE
ADDR 51 52 53 54 DISPLAY HANDLER
-- 10-30-78 -DISPLC PAGE 114
5109 F570 A5 66
LDA TOADR
5110 F572 69 28 ADC
#40
5111
F574
85 66
STA TOADR
5112 FB76 90 02
BCC MOVLI2
5113 F578 E6 67 INC TOADR+l
5114 F57A 60
MOVLI2: RTS
5115
5116
5117
5118
i
EXTEND: EXTEND BIT MAP FROM ROWCRS (EXTEND LOGICAL LINE
5119
5120 FB7B 08
EXTEND: PHP
i
SAVE CARRY
5121 FB7C AO 17 LDY
#23
5122
FB7E
98
EXTEN1 : TYA
5123 F57F 20 22 FB JSR L01GET
5124 FB82 08
PHP
5125 FB83 98 TYA
5126 FB84 18 CLC
5127
FB85 69 79 ADC #121
5128 FB87 28
PLP
5129 FB88 20 04 FB
JSR BITPUT
5130 FB8B 88 EXTEN3: DEY
5131 FB8C 30 04
BMI EXTEN4
5132 FB8E C4 54
CPY ROWCRS
5133 FB90 BO EC BCS EXTEN1
5134
FB92 A5 54 EXTEN4: LDA ROWCRS
5135
FB94
18
CLC
5136 FB95 69 78
ADC #120
5137 FB97 28 PLP
5138
FB98 4C 04 FB JMP BITPUT
iSTORE NEW LINE'S BIT AND RETURN
5139
5140
5141
5142
i
CLRLIN: CLEAR LINE CURSOR IS ON
5143
5144
FB9B
AS 52
CLRLIN: LDA LMARGN
5145 FB9D 85 55 STA COLCRS
5146 FB9F 20 47 F9 JSR CONVRT
5147
FBA2 AO 27 LDY #39
5148
FBA4
A9 00
LDA #0
5149 FBA6 91 64
CLRLI 1: STA (ADRESS), Y
5150 FBA8
88
DEY
5151 FBA9 10 FB BPL CLRLI1
5152
FBAB 60 RTS
5153
5154
5155
5156
5157
;
SCROLL: SCROLL SCREEN
5158
5159 FBAC 20 FA FA SCROLL: JSR BITROL iROLL IN CARRY
5160
FBAF
A5 58
LDA SAVMSC iSET UP WORKING REGISTERS
5161 FBBl 85 64
STA ADRESS
5162 FBB3 A5 59 LDA SAVMSC+1