chapter6/CH6PRG3.LST:

10 REM first set up the display list
20 POKE 1536,112:REM 8 blank lines
30 POKE 1537,112:REM 8 blank lines
40 POKE 1538,112:REM 8 blank lines
50 FOR I=1 TO 12:REM Loop to put in display list
60 POKE 1536+3*I,71:REM BASIC mode 2 with LMS set
70 POKE 1536+3*I+1,0:REM Low byte of LMS operand
80 POKE 1536+3*I+2,I:REM High byte of LMS operand
90 NEXT I
100 POKE 1575,65:REM ANTIC JVB instruction
110 POKE 1576,0:REM Display list starts at $0600
120 POKE 1577,6
130 REM tell ANTIC where display list is
140 POKE 560,0
150 POKE 561,6
160 REM now scroll horizontally
170 FOR I=0 TO 235:REM Loop through LMS low bytes
175 REM we use 235 --- not 255 --- because screen width is 20 characters
180 FOR J=1 TO 12:REM for each mode line
190 POKE 1536+3*J+1,I:REM Put in new LMS low byte
200 NEXT J
210 NEXT I
220 GOTO 170:REM Endless loop

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