APPENDIX ELEVEN



     1 DIM SEC$(128,Z$(1)
     2 REM SPACE FOR SECTOR DATA
     5 DATA 104,32,83,228,96
     10 FOR N=1536 TO 1540:READ X:POKE N,X:NEXT
        N
     15 REM POKE CIO CALL DATA INTO PAGE SIX
     20 PRINT "WHAT SECTOR TO COPY FROM?"
     25 INPUT START:IF START<0 OR START>720 THEN
        25
     30 PRINT "WHAT SECTOR TO COPY TO?"
     35 INPUT FINISH:IF FINISH<0 OR FINISH>720 O
        R FINISH=START THEN 35
     40 POKE 770,82:REM READ COMMAND
     45 POKE 778,START-(INT(START/256)*256):POKE
        779,INT(START/256)
     46 REM POKE LSB/MSB OF SECTOR TO COPY
     50 LOC=ADR(SEC$):POKE 772,LOC-(INT(LOC/256)
        *256):POKE 773,INT(LOC/256)
     55 REM POKE LSB/MSB OF ADDRESS OF DATA (SEC
        $) INTO BUFFER ADDRESS
     60 A=USR(1536):REM READ SECTOR INTO SEC$
     70 PRINT "PRESS RETURN TO WRITE SECTOR": INP
        UT Z$
     80 POKE 770,87:REM WRITE COMMAND
     85 POKE 778,FINISH-(INT(FINISH/256)*256):PO
        KE 779,INT(FINISH/256)
     86 REM POKE LSB/MSB OF SECTOR TO COPY TO
     90 A=USR(1536):REM WRITE IT
     100 GOTO 20

     See Antic magazine, December 1984, for more information about
     device control. Several magazines have published BASIC pro-
     grams to edit your disk by sectors, There are also good public
     domain programs of this sort on the Atari SIG on CompuServe.

769            301            DUNIT
     Current number of device being used.

771            303            DSTATS
     Status = 1 means good.

784,785        310,311        TIMER2
     Final baud rate timer value.