Stat LDA R0L | Apple II instruction

F717: A5 00	119	STAT	LDA	R0L
F719: 81 00	120	STAT2	STA	(R0L,X)	;STORE BYTE INDIRECT
F71B: A0 00	121		LDY	#$0
F71D: 84 1D	122	STAT3	STY	R14H	;INDICATE R0 IS RESULT NEG
F71F: F6 00	123	INR	INC	R0L,X
F721: D0 02	124		BNE	INR2	;INCR RX
F723: F6 01	125		INC	R0H,X
F725: 60	126	INR2	RTS
F726: A1 00	127	LDAT	LDA	(R0L,X)	;LOAD INDIRECT (RX)
F728: 85 00	128		STA	R0L	;TO R0
F72A: A0 00	129		LDY	#$0
F72C: 84 01	130		STY	R0H	;ZERO HIGH-ORDER R0 BYTE
F72E: F0 ED	131		BEQ	STAT3	;ALWAYS TAKEN
F730: A0 00	132	POP	LDY	#$0	;HIGH ORDER BYTE = 0
F732: F0 06	133		BEQ	POP2	;ALWAYS TAKEN
F734: 20 66 F7	134	POPD	JSR	DCR	;DECR RX
F737: A1 00	135		LDA	(R0L,X)	;POP HIGH ORDER BYTE @RX
F739: A8	136		TAY		;SAVE IN Y-REG
F73A: 20 66 F7	137	POP2	JSR	DCR	;DECR RX
F73D: A1 00	138		LDA	(R0L,X)	;LOW-ORDER BYTE
F73F: 85 00	139		STA	R0L	;TO R0
F741: 84 01	140		STY	R0H
F743: A0 00	141	POP3	LDY	#$0	;INDICATE R0 AS LAST RESULT REG
F745: 84 1D	142		STY	R14H
F747: 60	143		RTS
F748: 20 26 F7	144	LDDAT	JSR	LDAT	;LOW-ORDER BYTE TO R0, INCR RX
F74B: A1 00	145		LDA	(R0L,X)	;HIGH-ORDER BYTE TO R0
F74D: 85 01	146		STA	R0H
F74F: 4C 1F F7	147		JMP	INR	;INCR RX
F752: 20 17 F7	148	STDAT	JSR	STAT	;STORE INDIRECT LOW-ORDER
F755: A5 01	149		LDA	R0H	;BYTE AND INCR RX. THEN
F757: 81 00	150		STA	(R0L,X)	;STORE HIGH-ORDER BYTE.
F759: 4C 1F F7	151		JMP	INR	;INCR RX AND RETURN
F75C: 20 66 F7	152	STPAT	JSR	DCR	;DECR RX
F75F: A5 00	153		LDA	R0L
F761: 81 00	154		STA	(R0L,X)	;STORE R0 LOW BYTE @RX
F763: 4C 43 F7	155		JMP	POP3	;INDICATE R0 AS LAST RSLT REG
F766: B5 00	156	DCR	LDA	R0L,X
F768: D0 02	157		BNE	DCR2	;DECR RX
F76A: D6 01	158		DEC	R0H,X
F76C: D6 00	159	DCR2	DEC	R0L,X
F76E: 60	160		RTS
F76F: A0 00	161	SUB	LDY	#$0	;RESULT TO R0
F771: 38	162	CPR	SEC		;NOTE Y-REG = 13*2 FOR CPR
F772: A5 00	163		LDA	R0L
F774: F5 00	164		SBC	R0L,X
F776: 99 00 00	165		STA	R0L,Y	;R0-RX TO RY
F779: A5 01	166		LDA	R0H
F77B: F5 01	167		SBC	R0H,X
F77D: 99 01 00	168	SUB2	STA	R0H,Y
F780: 98	169		TYA		;LAST RESULT REG*2
F781: 69 00	170		ADC	#$0	;CARRY TO LSB
F783: 85 1D	171		STA	R14H
F785: 60	172		RTS
F786: A5 00	173	ADD	LDA	R0L
F788: 75 00	174		ADC	R0L,X
F78A: 85 00	175		STA	R0L	;R0+RX TO R0
F78C: A5 01	176		LDA	R0H
F78E: 75 01	177		ADC	R0H,X
F790: A0 00	178		LDY	#$0	;R0 FOR RESULT
F792: F0 E9	179		BEQ	SUB2	;FINISH ADD
F794: A5 1E	180	BS	LDA	R15L	;NOTE X-REG IS 12*2!

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 Stat LDA R0L

Models: II

STAT

LDA

R0L

II specifications