Crb, Eqs | Apple II guide

0243	A810	;	******************************
0244	A810	; REGISTERS FOR DISPLAY (6520)
0245	AC00		*=$AC00
0246	AC00	RA	.BLOCK 1	;REGISTER A
0247	AC01	CRA	.BLOCK 1	;CONTROL REG A
0248	AC02	RB	.BLOCK 1	;REG B
0249	AC03	CRB	.BLOCK 1	;CONTROL REG B
0250	AC04
0251	AC04	;CHR 00-03 ENA BY $AC04-AC07
0252	AC04	;CHR 04-07 ENA BY $AC08-AC0B
0253	AC04	;CHR 08-11 ENA BY $AC10-AC13
0254	AC04	;CHR 12-15 ENA BY $AC20-AC23
0255	AC04	;CHR 16-19 ENA BY $AC40-AC43
0256	AC04
0257	AC04	NULLC =$FF
0258	AC04	CR	=$0D
0259	AC04	LF	=$0A
0260	AC04	ESCAPE =$1B
0261	AC04	RUB	=$08
0262	AC04	EQS	=$BD
0263	AC04	;.FILE A1
0264	AC04
0265	AC04	; E=ENTER EDITOR
0266	AC04	; T=RE-ENTER EDITOR TO RE-EDIT SOURCE
0267	AC04	; R=SHOW REGISTERS
0268	AC04	; M=DISPLAY MEMORY
0269	AC04	;	=SHOW NEXT 4 ADDRESSES
0270	AC04	; G=GO AT CURRENT P.C. (COUNT)
0271	AC04	; /=ALTER CURRENT MEMORY
0272	AC04	; L=LOAD OBJECT
0273	AC04	; D=DUMP OBJECT
0274	AC04	; N=ASSEMBLE
0275	AC04	; *=ALTER P.C.
0276	AC04	; A=ALTER ACCUMULATOR
0277	AC04	; X=ALTER X REGISTER
0278	AC04	; Y=ALTER Y REGISTER
0279	AC04	; P=ALTER PROCESSOR STATUS
0280	AC04	; S=ALTER STACK POINTER
0281	AC04	; B=SET BREAK ADDR
0282	AC04	; ?=SHOW BREAK ADDRESSES
0283	AC04	; #=CLEAR BREAK ADDRESSES
0284	AC04	; H=SHOW TRACE HISTORY STACK
0285	AC04	; V=TOGGLE REGISTER PRINT WITH DIS.
0286	AC04	; Z=TOGGLE DISASSEMBLER TRACE
0287	AC04	; \=TURN ON/OFF PRINTER
0288	AC04	;	=ADV PAPER
0289	AC04	; I=MNEMONIC ENTRY
0290	AC04	; K=DISASSEMBLE MEMORY
0291	AC04	; 1=TOGGLE TAPE 1 CONTRL (ON OR OFF)
0292	AC04	; 2=TOGGLE TAPE 2 CONTRL
0293	AC04	; 3=VERIFY CKSUM FOR TAPES
0294	AC04	; 4=ENABLE BREAKS
0295	AC04	; 5=BASIC ENTRY (COLD)
0296	AC04	; 6=BASIC REENTRY (WARM)
0297	AC04
0298	AC04	;FOLLOWING KEYS ARE UNUSED BUT 'HOOKS'
0299	AC04	;ARE PROVIDED IN LOCATIONS 010C-0114
0300	AC04	;
0301	AC04	; KEYF1,KEYF2,KEYF3
0302	AC04
0303	E000		*=$E000
0304	E000	;ALL MSGS HAVE MSB=1 OF LAST CHAR TO END IT

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.

Apple II manual Crb, Eqs

Models: II

CRB

.BLOCK 1

;CONTROL REG B

EQS

II specifications