Classic Computer Magazine Archive COMPUTE! ISSUE 23 / APRIL 1982 / PAGE 12

"I'm 14 years old and own a Commodore PET 2001 with an 8K memory. I once heard of a program in COMPUTE! that would enable my PET to locate programs on fast forward. I also am making a RADAR with D/A and A/D converters and any information would be greatly appreciated on these topics. Thank you."

Matthew Silveira

This program, originally written by David Wilcox in 1978, can be adapted to any Commodore machine and can add to the speed and usefulness of a cassette-based computer system. The program is to be the first program on each tape, and lines 40 on should be updated to reflect whatever is stored on the tape. The computer then controls, and times, the cassette motor to quickly find a program's location.

The cassette is a serial device (where a series of items must be gone through, from item one, before a particular item can be reached). This program, however, makes the cassette a random access device when SAVEing or LOADing programs. It behaves the way a disk drive does, moving quickly and directly to the desired location.

10 PRINT" PRESS THE FAST-FORWARD KEY ON THE CASSETTE DRIVE NOW.
20 PRINT" THEN TYPE THE NUMBER OF THE PROGRAM YOU WISH TO USE.
30 PRINT" THE PROGRAMS ON THIS TAPE ARE:
40 PRINT" 0. FIRST PROGRAM'S NAME
50 PRINT" 1. SECOND PROGRAM'S NAME
60 PRINT" 2. ETC…
70 PRINT" 3. ETC…
80 PRINT" 4. ETC…
90 PRINT" 5. ETC…
100 GET N$:IFN$<>"" THEN130
110 IF PEEK(519)=0THEN POKE 519,52: POKE 59411,61
120 GOTO 100
130 N=ASC(LEFT$(N$,1))-48: PRINT"SEARCHING FOR"; N
140 POKE59411,53:TS = TI+N*600
150 IF TI>TS THEN 150
160 POKE59411,61
170 PRINT"{CLEAR} PRESS THE STOP KEY ON THE CASSETTE DRIVE AND THEN
180 PRINT"LOAD THE SELECTED PROGRAM NORMALLY.
190 PRINT"OR:
200 PRINT" SAVE A NEW PROGRAM ON THIS TAPE AT THIS LOCATION