0489

8308

60

 

 

 

RTS

 

 

0490

8309

29

0F

 

NIBASC AND #$0F

;NIBBLE IN A TO ASCII IN A

0491

830B

C9

0A

 

 

CMP #$0A

;LINE FEED

0492

830D

B0

04

 

 

BCS

NIBALF

 

0493

830F

69

30

 

 

ADC

#$30

 

0494

8311

90

02

 

 

BCC

EXITNB

 

0495

8313

69

36

 

NIBALF ADC

#$36

 

0496

8315

60

 

 

EXITNB RTS

 

 

0497

8316

20

4D

83

CRLFSZ JSR CRLF

;PRINT CRLF, FF, FE

0498

8319

A6

FF

 

 

LDX

$FF

 

0499

831B

A5

FE

 

 

LDA

$FE

 

0500

831D

4C

F4

82

 

JMP

OUTXAH

 

0501

8320

A9

3F

 

OUTQM

LDA

#'?'

 

0502

8322

4C

47

8A

 

JMP

OUTCHR

 

0503

8325

20

3A

83

OCMCK

JSR

COMMA

;OUT COMMA, CKSUM LO

0504

8328

AD 36 A6

 

LDA

SCR6

 

0505

832B

4C

FA 82

 

JMP

OUTBYT

 

0506

832E

A9

00

 

ZERCK

LDA

#0

;INIT CHECKSUM

0507

8330

8D

36

A6

 

STA

SCR6

 

0508

8333

8D

37

A6

 

STA

SCR7

 

0509

8336

60

 

 

 

RTS

 

 

0510

8337

20

EE 82

OPCCOM JSR OUTPC

;PC OUT, COMMA OUT

0511

833A

48

 

 

COMMA

PHA

 

;COMMA OUT

0512

833B

A9

2C

 

 

LDA

#','

 

0513

833D

D0

06

 

 

BNE

SPCP3

 

0514

833F

20

42

83

SPC2

JSR

SPACE

;2 SPACES OUT

0515

8342

48

 

 

SPACE

PHA

 

;1 SPACE OUT

0516

8343

A9

20

 

 

LDA

#$20

;SPACE

0517

8345

20

47

8A

SPCP3

JSR

OUTCHR

 

0518

8348

68

 

 

 

PLA

 

 

0519

8349

60

 

 

 

RTS

 

 

0520

834A

20

FA 82

OBCRLF JSR OUTBYT

;BYTE OUT, CRLF OUT

0521

834D

48

 

 

CRLF

PHA

 

 

0522

834E

A9

0D

 

 

LDA

#$0D

 

0523

8350

20

47

8A

 

JSR

OUTCHR

 

0524

8353

A9

0A

 

 

LDA

#$0A

;LINE FEED

0525

8355

20

47

8A

 

JSR

OUTCHR

 

0526

8358

68

 

 

 

PLA

 

 

0527

8359

60

 

 

 

RTS

 

 

0528

835A

AE 56 A6

DELAY

LDX

TV

;DELAY DEPENDS ON TV

0529

835D

20

88

81

DL1

JSR

SAVER

 

0530

8360

A9

FF

 

 

LDA

#$FF

 

0531

8362

8D

39

A6

 

STA

SCR9

 

0532

8365

8D

38

A6

 

STA

SCR8

 

0533

8368

0E

38

A6

DLY1

ASL

SCR8

;(SCR9,8)=FFFF-2**X

0534

836B

2E

39

A6

 

ROL

SCR9

 

0535

836E

CA

 

 

 

DEX

 

 

0536

836F

D0

F7

 

 

BNE

DLY1

 

0537

8371

20

03

89

DLY2

JSR

IJSCNV

;SCAN DISPLAY

0538

8374

20

86

83

 

JSR

INSTAT

;SEE IF KEY DOWN

0539

8377

B0

0A

 

 

BCS

DLY0

 

0540

8379

EE 38 A6

 

INC

SCR8

;SCAN 2**X+1 TIMES

0541

837C

D0

03

 

 

BNE

*+5

 

0542

837E

EE 39 A6

 

INC

SCR9

 

0543

8381

D0

EE

 

 

BNE

DLY2

 

0544

8383

4C

BE 81

DLY0

JMP

RESXF

 

0545

8386

 

 

 

; INSTAT -

SEE IF KEY DOWN, RESULT IN CARRY

0546

8386

 

 

 

; KEYSTAT,

TSTAT RETURN IMMEDIATELY W/STATUS

0547

8386

 

 

 

; INSTAT WAITS FOR RELEASE

0548

8386

20

92

83

INSTAT JSR

INJISV

 

0549

8389

90

06

 

 

BCC

INST2

 

0550

838B

20

92

83

INST1

JSR

INJISV

 

 

 

 

 

 

 

 

 

 

Page 110
Image 110
Apple II manual Nibasc and #$0F Nibble in a to Ascii in a

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.