0181

A484

; WRITE EDGE

DETECT CONTROL (NOT USED BECAUSE KB)

 

0182

A484

 

 

*=$A484

 

 

 

 

0183

A484

DNPA7

 

.BLOCK

1

;DISABLE PA7 INT ,NEG EDGE DET

0184

A485

DPPA7

 

.BLOCK

1

;DIS PA7 INT ,POS EDGE DETE

 

0185

A486

ENPA7

 

.BLOCK

1

;ENA PA7 INT ,NEG EDG DET

 

0186

A487

EPPA7

 

.BLOCK

1

;ENA PA7 INT ,POS EDG DET

 

0187

A488

 

 

 

 

 

 

 

0188

A488

;

 

READ AND CLEAR INTERRUPT

 

 

0189

A485

 

 

*=$A485

 

 

 

 

0190

A485

RINT

 

.BLOCK

1

;BIT 7=TIMER FLG , BIT 6=PA7 FLG

0191

A486

 

 

 

 

 

 

 

0192

A486

;

 

 

TIMER INTERRUPT

 

 

0193

A494

 

 

*=$A494

 

 

 

 

0194

A494

;WRITE COUNT TO INTERVAL TIMER

 

 

0195

A494

;INTERRUPT DISABLE FOR THESE ADDRS

 

 

0196

A494

DIV1

 

.BLOCK

1

;DIV BY 1 (DISABLE);ADD 8 TO ENA

0197

A495

DIV8

 

.BLOCK

1

;DIV BY 8 (DIS) ; ADD 8 TO ENA

0198

A496

DIV64

 

.BLOCK

1

;DIV BY 64 (DIS) ; ADD 8 TO ENA

0199

A497

DI1024 .BLOCK

1

;DIV BY 1024 (DIS) ; ADD 8 TO ENA

0200

A498

 

 

 

 

 

 

 

0201

A498

;

*********************************************

0202

A498

;

*

6522

ADDRESSES (MONIT) (A800-ABFF)

*

0203

A498

;

*********************************************

0204

A800

 

 

*=$A800

 

 

 

 

0205

A800

DRB

 

.BLOCK

1

;DATA REG B

 

 

0206

A801

DRAH

 

.BLOCK

1

;DATA REG A

 

 

0207

A802

DDRB

 

.BLOCK

1

;DATA DIR REG B

 

 

0208

A803

DDRA

 

.BLOCK

1

;DATA DIR REG A

 

 

0209

A804

T1L

 

.BLOCK

1

;TIMER 1 COUNTER LOW

 

0210

A805

T1CH

 

.BLOCK

1

;TIMER 1 COUNTER HIGH

 

0211

A806

T1LL

 

.BLOCK

1

;TIMER 1 LATCH LOW

 

0212

A807

T1LH

 

.BLOCK

1

;TIMER 1 LATCH HIGH

 

0213

A808

T2L

 

.BLOCK

1

;TIMER 2 LATCH & COUNTER LOW

0214

A809

T2H

 

.BLOCK

1

;TIMER 2 COUNTER HIGH

 

0215

A80A

SR

 

.BLOCK

1

;SHIFT REGISTER

 

 

0216

A80B

ACR

 

.BLOCK

1

;AUX CONTROL REGISTER

 

0217

A80C

PCR

 

.BLOCK

1

;PERIPHERAL CONTROL REGISTER

0218

A80D

IFR

 

.BLOCK

1

;INTERRUPT FLAG REGISTER

 

0219

A80E

IER

 

.BLOCK

1

;INTERRUPT ENABLE REGISTER

 

0220

A80F

DRA

 

.BLOCK

1

;DATA REGISTER A

 

0221

A810

 

 

 

 

 

 

 

0222

A810

;DEFINE I/O CONTROL FOR PCR (CA1,CA2,CB1,CB2)

 

0223

A810

DATIN

 

=$0E

 

;DATA IN CA2=1

 

 

0224

A810

DATOUT

 

=$0C

 

;DATA OUT CA2=0

 

 

0225

A810

PRST

 

=$00

 

;PRINT START (CB1) ,NEG DETEC

0226

A810

SP12

 

=$01

 

;STROBE P1,P2

(CA1) ,POS DETEC

0227

A810

MON

 

=$C0

 

;MOTOR ON (CB2=0)

 

0228

A810

MOFF

 

=$E0

 

 

 

 

0229

A810

;MSKS TO OBTAIN EACH INTERRUPT

 

 

0230

A810

MPRST

 

=$10

 

;INT FLG FOR CB1

 

0231

A810

MSP12

 

=$02

 

;INT FLG FOR CA1

 

0232

A810

MT2

 

=$20

 

;INT FLG FOR T2

 

 

0233

A810

 

 

 

 

 

 

 

0234

A810

;DEFINE I/O CONTROL FOR ACR (TIMERS,SR)

 

0235

A810

PRTIME =1700

 

; PRINTING TIME =1.7M MSEC

 

0236

A810

DEBTIM =5000

 

; DEBOUNCE TIME (5 MSEC)

 

0237

A810

T2I

 

=$00

 

;T2 AS ONE SHOT (PRI,KB,TTY,TAPE)

0238

A810

T1I

 

=$00

 

;T1 AS ONE SHOT,PB7 DIS (TAPES)

0239

A810

T1FR

 

=$C0

 

;T1 IN FREE RUNNING (TAPE)

 

0240

A810

 

 

 

 

 

 

 

0241

A810

;

 

******************************

 

0242

A810

;

 

*

 

DISPLAY (AC00-AFFF)

*

 

 

 

 

 

 

 

 

 

 

Page 142 Page 144
Page 143
Image 143
Apple II manual Write Edge Detect Control not Used Because KB
Page 142 Page 144

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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