0119

A416

CURPOS

.BLOCK

1

;PRINTER POINTER

0120

A417

CNTH30

.BLOCK

1

;BAUD RATE &...

0121

A418

CNTL30

.BLOCK

1

;DELAY FOR TTY

0122

A419

COUNT

.BLOCK

1

;# OF LINES (0-99)

0123

A41A

S1

.BLOCK

2

;START ADDRESS

0124

A41C

ADDR

.BLOCK

2

;END ADDRESS

0125

A41E

CKSUM

.BLOCK

2

;CHECKSUM

 

0126

A420

S2

=BKS+6

 

;VERTICAL COUNT (ONLY ON DUMP)

0127

A420

 

 

 

 

 

0128

A420

;MONITOR REGISTERS

 

0129

A420

SAVPS

.BLOCK

1

;STATUS

 

0130

A421

SAVA

.BLOCK

1

;ACCUM

 

0131

A422

SAVX

.BLOCK

1

;X REG

 

0132

A423

SAVY

.BLOCK

1

;Y REG

 

0133

A424

SAVS

.BLOCK

1

;STACK POINTER

0134

A425

SAVPC

.BLOCK

2

;PROGR COUNTER

0135

A427

 

 

 

 

 

0136

A427

;WORK AREAS FOR PAGE ZERO SIMULATION

0137

A427

;SIMULATE LDA

(NNNN),Y ,WHERE NNNN IS ABSOLUTE

0138

A427

STIY

.BLOCK

3

;STA NM,Y

 

0139

A42A

CPIY

.BLOCK

3

;CMP NM,Y

OR LDA NM,Y

0140

A42D

 

.BLOCK

1

;RTS

 

0141

A42E

LDIY

=CPIY

 

;LDA NM,Y

 

0142

A42E

 

 

 

 

 

0143

A42E

;VARIABLES FOR TAPE

 

0144

A42E

NAME

.BLOCK

6

;FILE NAME

0145

A434

TAPIN

.BLOCK

1

;IN FLG (TAPE 1 OR 2)

0146

A435

TAPOUT

.BLOCK

1

;OUT FLG (TAPE 1 OR 2)

0147

A436

TAPTR

.BLOCK

1

;TAPE BUFF POINTER

0148

A437

TAPTR2

.BLOCK

1

;TAPE OUTPUT BUFF PTR

0149

A438

HIST

=NAME

 

;FOUR LAST ADDR + NEXT (SINGL STEP)`

0150

A438

BLK

=$0115

 

;BLOCK COUNT

0151

A438

TABUFF

=$0116

 

;TAPE BUFFER (I/O)

0152

A438

BLKO

=$0168

 

;OUTPUT BLOCK COUNT

0153

A438

TABUF2

=$00AD

 

;OUTPUT BUFF WHEN ASSEMB (PAG0)

0154

A438

DIBUFF .BLOCK

40

;DISPLAY BUFFER

0155

A460

 

 

 

 

 

0156

A460

;VARIABLES USED

IN PRINTING

 

0157

A460

IBUFM

.BLOCK

20

;PRINTER BUFFER

0158

A474

IDIR

.BLOCK

1

;DIRECTION == 0=>+ , FF=>-

0159

A475

ICOL

.BLOCK

1

;COLUMN

LEFTMOST=0,RIGHTMOST=4

0160

A476

IOFFST

.BLOCK

1

;OFFSET

0=LEFT DGT,1=RIGHT DGT

0161

A477

IDOT

.BLOCK

1

;# OF LAST DOT ENCOUNTERED

0162

A478

IOUTL

.BLOCK

1

;LOWER 8 OUTPUTS(8 COLS ON RIGHT)

0163

A479

IOUTU

.BLOCK

1

;UPPER 2 DIGITS

0164

A47A

IBITL

.BLOCK

1

;1 BIT MSK FOR CURRENT OUTPUT

0165

A47B

IBITU

.BLOCK

1

 

 

0166

A47C

IMASK

.BLOCK

1

;MSK FOR CURRENT ROW

0167

A47D

JUMP

.BLOCK

2

;INDIR & ADDR OF TABL FOR CURR ROW

0168

A47F

 

 

 

 

 

0169

A47F

;VARIABLES FOR KEYBOARD

 

0170

A47F

ROLLFL .BLOCK

1

;SAVE LAST STROBE FOR ROLLOVER

0171

A480

KMASK

=CPIY

 

;TO MASK OFF CTRL OR SHIFT

0172

A480

STBKEY =CPIY+1

 

;STROBE KEY (1-8 COLUMNS)

0173

A480

 

 

 

 

 

0174

A480

;

 

 

I/O ASSIGNMENT

 

0175

A480

 

*=$A480

 

 

 

0176

A480

DRA2

.BLOCK

1

;DATA REG A

0177

A481

DDRA2

.BLOCK

1

;DATA DIR REG A

0178

A482

DRB2

.BLOCK

1

;DATA REG B

0179

A483

DDRB2

.BLOCK

1

;DATA DIR REG B

0180

A484

 

 

 

 

 

 

 

 

 

 

 

 

Page 141 Page 143
Page 142
Image 142
Apple II manual Curpos, Checksum, Tabuff, TABUF2
Page 141 Page 143

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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