Disk Expander For Apple II

Boris Troyanovsky

Everyone can use more disk space. This program allows you to format DOS 3.3 disks with an extra track of space, giving you 16 more disk sectors for storage.

Here is a utility that gives you extra storage space on any DOS 3.3 disk. After formatting a disk with this program, you have 16 extra disk sectors for storing programs and other files. Type in the program and save it to disk.

When you run the program, it waits for you to press a key. Insert a blank disk into slot 6, drive 1 (this is the built-in drive on Apple IIc computers). Press any key to begin. When the drive stops spinning, the disk has been formatted with 16 extra sectors. Now you can save a HELLO program on the disk or use it as you would a normal DOS 3.3 disk. The FID program on the DOS 3.3 System Master disk can be used to verify that the disk really does contain the extra space.

Disk Expander for Apple II

For Instructions on entering this program, please refer to "COMPUTE!'s Guide to Typing In Programs" elsewhere in this Issue.

BA 10 D$ = CHR$ (4) : G0SUB 200
IA 20 TEXT : HOME : HTAB 17 : PRINT "D.M.E.S." : VTAB 1 : FOR X = 1 TO 16 : HTAB X : PRINT "-"; : NEXT X : FOR X = 25 TO 40 : HTAB X : PRINT "-" ; : NEXT X
BF 30 VTAB 13 : PRINT "INSERT DISK INTO SLOT 6, DRIVE l" : PRINT "AND PRESS ANY KEY" : GET A$
9B 40 PRINT
3D 50 REM *** EXPAND DISK CAP.***
39 60 POKE 48894, PEEK (48894) + 1
89 70 PRINT D$; "INIT HELL0, D1, S6" : PRINT D$; "DELETE HELLO"
3C 80 POKE 48894, PEEK (48894) - 1
2A 90 SS = 0 : SE = 0 : BU = 8192 : OP = 1 : TR = 17 : GOSUB 130
18 100 POKE 8192 + 196, 255 : POKE 8192 + 197; 255 : POKE 8192 + 52, 36
F6 110 SS = 0 : SE = 0 : BU = 8192 : OP = 2 : TR = 17 : GOSUB 130
AD 120 GOTO 20
5C 130 REM ***DISK ACCESS***
85 140 FOR SA = SS TO SE
F7 150 POKE 788, TR : POKE 789, SA : POKE 796, OP
C7 160 HB = INT (BU / 256) : LB = BU - (HB * 256)
6E 170 POKE 792, LB : POKE 793, HB
27 180 CALL 768 : BU = BU + 256 : NEXT SA
23 190 RETURN
37 200 FOR I = 768 TO 822 : READ A : POKE I, A : NEXT I : RETURN
9B 210 DATA 169, 3, 160, 16, 32, 217, 3, 96, 0, 0, 0
7C 220 DATA 0, 0, 0, 0, 0, 1, 96, 1, 0, 17, 13
C2 230 DATA 48, 3, 0, 32, 0, 0, 1, 0, 254, 96, 1
20 240 DATA 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
3C 250 DATA 0, 0, 0, 0, 0, 1, 239, 216, 0, 0, 0