SBC PCL Form ADDR-PC-2 | Apple II specification

F50D: 8A	57		TXA
F50E: 18	58		CLC
F50F: E5 3A	59		SBC	PCL	;FORM ADDR-PC-2
F511: 85 3E	60		STA	A2L
F513: 10 01	61		BPL	REL3
F515: C8	62		INY
F516: 98	63	REL3	TYA
F517: E5 3B	64		SBC	PCH
F519: D0 6B	65	ERR3	BNE	ERR	;ERROR IF >1-BYTE BRANCH
F51B: A4 2F	66	FINDOP	LDY	LENGTH
F51D: B9 3D 00	67	FNDOP2	LDA	A1H,Y	;MOVE INST TO (PC)
F520: 91 3A	68		STA	(PCL),Y
F522: 88	69		DEY
F523: 10 F8	70		BPL	FNDOP2
F525: 20 1A FC	71		JSR	CURSUP
F528: 20 1A FC	72		JSR	CURSUP	;RESTORE CURSOR
F52B: 20 D0 F8	73		JSR	INSTDSP	;TYPE FORMATTED LINE
F52E: 20 53 F9	74		JSR	PCADJ	;UPDATE PC
F531: 84 3B	75		STY	PCH
F533: 85 3A	76		STA	PCL
F535: 4C 95 F5	77		JMP	NXTLINE	;GET NEXT LINE
F538: 20 BE FF	78	FAKEMON3 JSR		TOSUB	;GO TO DELIM HANDLER
F53B: A4 34	79		LDY	YSAV	;RESTORE Y-INDEX
F53D: 20 A7 FF	80	FAKEMON	JSR	GETNUM	;READ PARAM
F540: 84 34	81		STY	YSAV	;SAVE Y-INDEX
F542: A0 17	82		LDY	#$17	;INIT DELIMITER INDEX
F544: 88	83	FAKEMON2 DEY			;CHECK NEXT DELIM
F545: 30 4B	84		BMI	RESETZ	;ERR IF UNRECOGNIZED DELIM
F547: D9 CC FF	85		CMP	CHRTBL,Y	;COMPARE WITH DELIM TABLE
F54A: D0 F8	86		BNE	FAKEMON2	;NO MATCH
F54C: C0 15	87		CPY	#$15	;MATCH, IS IT CR?
F54E: D0 E8	88		BNE	FAKEMON3	;NO, HANDLE IT IN MONITOR
F550: A5 31	89		LDA	MODE
F552: A0 00	90		LDY	#$0
F554: C6 34	91		DEC	YSAV
F556: 20 00 FE	92		JSR	BL1	;HANDLE CR OUTSIDE MONITOR
F559: 4C 95 F5	93		JMP	NXTLINE
F55C: A5 3D	94	TRYNEXT	LDA	A1H	;GET TRIAL OPCODE
F55E: 20 8E F8	95		JSR	INSDS2	;GET FMT+LENGTH FOR OPCODE
F561: AA	96		TAX
F562: BD 00 FA	97		LDA	MNEMR,X	;GET LOWER MNEMONIC BYTE
F565: C5 42	98		CMP	A4L	;MATCH?
F567: D0 13	99		BNE	NEXTOP	;NO, TRY NEXT OPCODE.
F569: BD C0 F9	100		LDA	MNEML,X	;GET UPPER MNEMONIC BYTE
F56C: C5 43	101		CMP	A4H	;MATCH?
F56E: D0 0C	102		BNE	NEXTOP	;NO, TRY NEXT OPCODE
F570: A5 44	103		LDA	FMT
F572: A4 2E	104		LDY	FORMAT	;GET TRIAL FORMAT
F574: C0 9D	105		CPY	#$9D	;TRIAL FORMAT RELATIVE?
F576: F0 88	106		BEQ	REL	;YES.
F578: C5 2E	107	NREL	CMP	FORMAT	;SAME FORMAT?
F57A: F0 9F	108		BEQ	FINDOP	;YES.
F57C: C6 3D	109	NEXTOP	DEC	A1H	;NO, TRY NEXT OPCODE
F57E: D0 DC	110		BNE	TRYNEXT
F580: E6 44	111		INC	FMT	;NO MORE, TRY WITH LEN=2
F582: C6 35	112		DEC	L	;WAS L=2 ALREADY?
F584: F0 D6	113		BEQ	TRYNEXT	;NO.
F586: A4 34	114	ERR	LDY	YSAV	;YES, UNRECOGNIZED INST.
F588: 98	115	ERR2	TYA
F589: AA	116		TAX
F58A: 20 4A F9	117		JSR	PRBL2	;PRINT ^ UNDER LAST READ
F58D: A9 DE	118		LDA	#$DE	;CHAR TO INDICATE ERROR

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 SBC PCL Form ADDR-PC-2

Models: II

SBC

PCL

;FORM ADDR-PC-2

II specifications