BCS INST1 | Apple II instruction

0551	838E	B0	FB			BCS	INST1
0552	8390	38				SEC
0553	8391	60			INST2	RTS
0554	8392	6C	67	A6	INJISV JMP		(INSVEC+1)
0555	8395				;
0556	8395				;
0557	8395				; *** EXECUTE BLOCKS BEGIN HERE
0558	8395				;
0559	8395				BZPARM =*
0560	8395				; ZERO PARM COMMANDS
0561	8395				;
0562	8395	C9	52		REGZ	CMP #'R'		;DISP REGISTERS
0563	8397	D0	5A			BNE GOZ		;PC,S,F,A,X,Y
0564	8399	20	4D	83	RGBACK JSR		CRLF
0565	839C	A9	50			LDA	#'P'
0566	839E	20	47	8A		JSR	OUTCHR
0567	83A1	20	42	83		JSR	SPACE
0568	83A4	20	EE 82			JSR	OUTPC
0569	83A7	20	D6	81		JSR	COMINB
0570	83AA B0 13					BCS	NH3
0571	83AC 8D 34 A6					STA	SCR4
0572	83AF 20 D9 81					JSR	INBYTE
0573	83B2	B0	0B			BCS	NH3
0574	83B4	8D	59	A6		STA	PCLR
0575	83B7	AD 34 A6				LDA	SCR4
0576	83BA 8D 5A A6					STA	PCHR
0577	83BD 90 09					BCC	M34
0578	83BF D0 02				NH3	BNE	NOTCR
0579	83C1	18			EXITRG CLC
0580	83C2	60			EXRGP1 RTS
0581	83C3	20	CB 81		NOTCR	JSR	ADVCK
0582	83C6	D0	FA			BNE	EXRGP1
0583	83C8	A0	00		M34	LDY	#0
0584	83CA C8				M35	INY
0585	83CB C0 06					CPY	#6
0586	83CD F0 CA					BEQ	RGBACK
0587	83CF 20 4D 83					JSR	CRLF
0588	83D2	B9	99	8F		LDA	RGNAM-1,Y	;GET REG NAME
0589	83D5				; OUTPUT 3		SPACES TO LINE UP DISPLAY
0590	83D5	20	47	8A		JSR	OUTCHR
0591	83D8	20	42	83		JSR	SPACE
0592	83DB 20 3F 83					JSR	SPC2
0593	83DE B9 5A A6					LDA	PCHR,Y
0594	83E1	20	D3	81		JSR	OBCMIN
0595	83E4	B0	05			BCS	M36
0596	83E6	99	5A	A6		STA	PCHR,Y
0597	83E9	90	DF			BCC	M35
0598	83EB F0 D4				M36	BEQ	EXITRG
0599	83ED 20 CB 81					JSR	ADVCK
0600	83F0	F0	D8			BEQ	M35
0601	83F2	60				RTS
0602	83F3	C9	47		GOZ	CMP	#'G'
0603	83F5	D0	20			BNE	LPZB
0604	83F7	20	4D	83		JSR	CRLF
0605	83FA 20 9C 8B				GO1ENT JSR		NACCES	;WRITE PROT MONITOR RAM
0606	83FD AE 5B A6					LDX	SR	;RESTORE REGS
0607	8400	9A				TXS
0608	8401	AD 5A A6				LDA	PCHR
0609	8404	48				PHA
0610	8405	AD 59 A6				LDA	PCLR
0611	8408	48			NR10	PHA
0612	8409	AD 5C A6				LDA	FR

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.

BCS

INST1

CMP

II specifications