is => the final value, then the first state-

 

ment following the FOR statement is

 

executed. Otherwise, the statement

 

following the NEXT statement is executed.

 

All FOR loops execute the statements

 

between the FOR and the NEXT at least

 

once, even in cases like FOR V=1 TO 0.

 

Note that expressions (formulas) may be

 

used for the initial, final and step values

 

in a FOR loop. The values of the expres-

 

sions are computed only once, before the

 

body of the FOR...NEXT loop is

 

executed.

 

When the statement after the NEXT is

 

executed, the loop variable is never equal

 

to the final value, but is equal to whatever

 

value caused the FOR...NEXT loop to

 

terminate. The statements between the

 

FOR and its corresponding NEXT in both

 

examples above (310 and 320) would be

 

executed nine times.

 

Error: do not use nested FOR...NEXT

 

loops with the same index variable.

 

FOR loop nesting is limited only by the

 

available memory. (See Appendix C.)

STATEMENT

SYNTAX/FUNCTION

GOSUB

GOSUB line number

 

Branches to the specified statement (910)

 

until a RETURN is encountered; when a

 

branch is then made to the statement after

 

the GOSUB. GOSUB nesting is limited

 

only by the available memory.

STATEMENT

SYNTAX/FUNCTION

GOTO

GOTO line number

 

Branches to the statement specified.

STATEMENT

SYNTAX/FUNCTION

IF...GOTO

IF expression GOTO line number ...

 

Equivalent to IF...THEN, except that

 

IF...GOTO must be followed by a line

 

number, while IF...THEN can be

 

followed by either a line number or

 

another statement.

STATEMENT

SYNTAX/FUNCTION

IF...THEN

IF expression THEN line number ...

 

Branches to specified statement if the

 

relation is True.

 

Executes all of the statements on the

 

remainder of the THEN if the relation

 

is True.

 

WARNING: The "Z=A" will never be

 

executed because if the relation is true,

 

BASIC will branch to line 50. If the

 

relation is false BASIC will proceed to

 

to the line following line 25.

315 FOR V=10*N TO 3.4/Q STEP SQR(R)

320 FOR V=9 TO 1 STEP -1

330 FOR W=1 TO 10: FOR W=1 TO 5:NEXT

W:NEXT W

EXAMPLE

10 GOSUB 910

EXAMPLE

50 GOTO 100

EXAMPLE

32 IF X<=Y+23.4 GOTO 92

EXAMPLE

IF X<10 THEN 5

20 IF X<0 THEN PRINT "X LESS THAN 0"

25 IF X=5 THEN 50:Z=A

Page 239 Page 241
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Apple II manual Statement SYNTAX/FUNCTION Gosub, Statement SYNTAX/FUNCTION Goto, Statement SYNTAX/FUNCTION IF...GOTO
Page 239 Page 241

II specifications

The Apple II, launched in April 1977, was one of the first highly successful mass-produced microcomputer products. It marked a significant leap in personal computing, setting standards for future developments in the industry. Created by Steve Wozniak and Steve Jobs, the Apple II differentiated itself with its user-friendly design, appealing aesthetics, and robust capabilities.

One of the standout features of the Apple II was its open architecture, which allowed users to expand and enhance the computer's functionality. This design enabled hundreds of third-party hardware and software developers to contribute to its ecosystem, resulting in an array of peripherals, including printers, modems, and storage devices. The Apple II utilized a MOS Technology 6502 microprocessor running at a clock speed of 1 MHz. Initially equipped with 4 KB of RAM, the machine could be expanded to 48 KB, accommodating more complex applications and programs.

The Apple II was also notable for its colorful graphics. It was one of the first computers to support color display, offering a 6-color palette with a resolution of 280x192 pixels in 16 colors when using its Color Graphics Card. This feature significantly enhanced the visual appeal of games and educational software developed for the platform, making computing more accessible and entertaining for various audiences.

Apple's commitment to user experience was evident in the design of the machine. It featured an integrated keyboard and a plastic case, which was both durable and visually appealing. The self-contained design included drive bays for floppy disk drives, allowing for quicker data access than traditional tape drives. It also supported audio output, enabling sound effects and music, a novelty at the time.

The introduction of the Apple DOS operating system further underscored the machine's capabilities. DOS streamlined file management and made it easier for users to navigate and manage their data. The combination of hardware and software positioned the Apple II as an educational tool and a gaming platform, fostering a vibrant software ecosystem.

The Apple II family continued to evolve, with variations like the Apple II+, IIe, and IIgs being introduced over the years. These iterations brought enhancements in memory, processing power, and graphics capabilities. The legacy of the Apple II endures, not only as a foundational product in personal computing but also as a symbol of innovation that paved the way for future advancements in technology. Its impact is still felt today, as it inspired countless developers and shaped the trajectory of the computer industry.
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