FDAD: A5 3C

829

MODSCHK

LDA

A1L

 

 

FDAF: 29 07

830

 

AND

#$07

 

 

FDB1: D0 03

831

 

BNE

DATAOUT

 

 

FDB3: 20 92 FD

832

XAM

JSR

PRA1

 

 

FDB6: A9 A0

833

DATAOUT

LDA

#$A0

 

 

FDB8: 20 ED FD

834

 

JSR

COUT

;OUTPUT BLANK

FDBB: B1 3C

835

 

LDA

(A1L),Y

 

 

FDBD: 20 DA FD

836

 

JSR

PRBYTE

;OUTPUT BYTE IN HEX

FDC0: 20 BA FC

837

 

JSR

NXTA1

 

 

FDC3: 90 E8

838

 

BCC

MODSCHK

;CHECK IF TIME TO,

FDC5: 60

839

RTS4C

RTS

 

;

PRINT ADDR

FDC6: 4A

840

XAMPM

LSR

 

;DETERMINE IF MON

FDC7: 90 EA

841

 

BCC

XAM

;

MODE IS XAM

FDC9: 4A

842

 

LSR

 

;

ADD, OR SUB

FDCA: 4A

843

 

LSR

 

 

 

FDCB: A5 3E

844

 

LDA

A2L

 

 

FDCD: 90 02

845

 

BCC

ADD

 

 

FDCF: 49 FF

846

 

EOR

#$FF

;SUB: FORM 2'S COMPLEMENT

FDD1: 65 3C

847

ADD

ADC

A1L

 

 

FDD3: 48

848

 

PHA

 

 

 

FDD4: A9 BD

849

 

LDA

#$BD

 

 

FDD6: 20 ED FD

850

 

JSR

COUT

;PRINT '=', THEN RESULT

FDD9: 68

851

 

PLA

 

 

 

FDDA: 48

852

PRBYTE

PHA

 

;PRINT BYTE AS 2 HEX

FDDB: 4A

853

 

LSR

 

;

DIGITS, DESTROYS A-REG

FDDC: 4A

854

 

LSR

 

 

 

FDDD: 4A

855

 

LSR

 

 

 

FDDE: 4A

856

 

LSR

 

 

 

FDDF: 20 E5 FD

857

 

JSR

PRHEXZ

 

 

FDE2: 68

858

 

PLA

 

 

 

FDE3: 29 0F

859

PRHEX

AND

#$0F

;PRINT HEX DIG IN A-REG

FDE5: 09 B0

860

PRHEXZ

ORA

#$B0

;

LSB'S

FDE7: C9 BA

861

 

CMP

#$BA

 

 

FDE9: 90 02

862

 

BCC

COUT

 

 

FDEB: 69 06

863

 

ADC

#$06

 

 

FDED: 6C 36 00

864

COUT

JMP

(CSWL)

;VECTOR TO USER OUTPUT ROUTINE

FDF0: C9 A0

865

COUT1

CMP

#$A0

 

 

FDF2: 90 02

866

 

BCC

COUTZ

;DON'T OUTPUT CTRL'S INVERSE

FDF4: 25 32

867

 

AND

INVFLG

;MASK WITH INVERSE FLAG

FDF6: 84 35

868

COUTZ

STY

YSAV1

;SAV Y-REG

FDF8: 48

869

 

PHA

 

;SAV A-REG

FDF9: 20 FD FB

870

 

JSR

VIDOUT

;OUTPUT A-REG AS ASCII

FDFC: 68

871

 

PLA

 

;RESTORE A-REG

FDFD: A4 35

872

 

LDY

YSAV1

;

AND Y-REG

FDFF: 60

873

 

RTS

 

;

THEN RETURN

FE00: C6 34

874

BL1

DEC

YSAV

 

 

FE02: F0 9F

875

 

BEQ

XAM8

 

 

FE04: CA

876

BLANK

DEX

 

;BLANK TO MON

FE05: D0 16

877

 

BNE

SETMDZ

;AFTER BLANK

FE07: C9 BA

878

 

CMP

#$BA

;DATA STORE MODE?

FE09: D0 BB

879

 

BNE

XAMPM

;

NO, XAM, ADD, OR SUB

FE0B: 85 31

880

STOR

STA

MODE

;KEEP IN STORE MODE

FE0D: A5 3E

881

 

LDA

A2L

 

 

FE0F: 91 40

882

 

STA

(A3L),Y

;STORE AS LOW BYTE AS (A3)

FE11: E6 40

883

 

INC

A3L

 

 

FE13: D0 02

884

 

BNE

RTS5

;INCR A3, RETURN

FE15: E6 41

885

 

INC

A3H

 

 

FE17: 60

886

RTS5

RTS

 

 

 

FE18: A4 34

887

SETMODE

LDY

YSAV

;SAVE CONVERTED ':', '+',

FE1A: B9 FF 01

888

 

LDA

IN-1,Y

;

'-', '.' AS MODE.

FE1D: 85 31

889

SETMDZ

STA

MODE

 

 

FE1F: 60

890

 

RTS

 

 

 

 

 

 

 

 

 

 

Page 32 Page 34
Page 33
Image 33
Apple II manual Fdad A5 3C
Page 32 Page 34

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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