This machine code routine uses a vertical blank interrupt to flash the cursor on any Atari. In the routine it decreases memory location 71. When this reaches zero it turns the cursor off (using POKE 755,0), then repeats this but turns the cursor back on (using POKE 755,2). As POKE 755,0 also turns off inverse characters, this routine also flashes anything printer or typed in inverse.
After running this program it will continue until the computer is turned off or reset is pressed (typing A=USR(1536) restarts the routine).
To change the speed at which the cursor flashes, alter line 105. Replace this number by the speed you want. The higher the number is, the slower the cursor will flash. After doing this RUN it and NEW it. If you wish to change the speed type POKE 1538,speed (speed being the number for your speed) then type A=USR(1536).
5 REM FLASHING CURSOR BY JASON GOSLING
10 FOR N=1536 TO 1592: READ I:POKE N,I:NEXT N
20 A=USR(1536)
30 END
100 DATA 104,169
105 DATA 16
110 DATA 133,70,165,70,133,71,160,19,162,6,169,7,32,92,228,96
115 DATA 198,71,240,3,76,98,228
120 DATA 169,2,205,243,2,240,12,169,2,141,243,2,165,70,133,71,76,98,228
130 DATA 169,0,141,243,2,165,70,133,71,76,98,228
19th January 1985
