BCC PACKT3 | Apple II manual

2039	8E3C C9 30			PACKT	CMP	#$30	;LT "0"?
2040	8E3E 90 1D				BCC	PACKT3
2041	8E40	C9	47		CMP	#$47	;GT "F" ?
2042	8E42	B0	19		BCS	PACKT3
2043	8E44	C9	40		CMP	#$40	;A-F?
2044	8E46	F0	15		BEQ	PACKT3	;40 NOT VALID
2045	8E48	90	03		BCC	PACKT1
2046	8E4A 18				CLC
2047	8E4B 69 09				ADC	#9
2048	8E4D 2A			PACKT1 ROL		A	;GET LSD INTO LEFT NIBBLE
2049	8E4E 2A				ROL	A
2050	8E4F 2A				ROL	A
2051	8E50	2A			ROL	A
2052	8E51	A0	04		LDY	#4
2053	8E53	2A		RACKT2 ROL		A	;ROTATE 1 BIT AT A TIME INTO CHAR
2054	8E54	26	FC		ROL	CHAR
2055	8E56	88			DEY
2056	8E57	D0	FA		BNE	RACKT2
2057	8E59	A5	FC		LDA	CHAR	;GET INTO ACCUM ALSO
2058	8E5B 18				CLC		;OK
2059	8E5C 60			RDRTN	RTS
2060	8E5D 38			PACKT3 SEC			;NOT HEX
2061	8E5E 60				RTS
2062	8E5F
2063	8E5F			; RDCHT - READ KIM CHAR
2064	8E5F			; PRESERVES X, RETURNS CHAR IN CHAR (W/PARITY)
2065	8E5F			; AND A (W/O PARITY)
2066	8E5F
2067	8E5F 8A			RDCHT	TXA		;SAVE X
2068	8E60	48			PHA
2069	8E61	A9	FF		LDA #$FF		;USE A TO COUNT BITS (BY SHIFTING)
2070	8E63	48		KBITS	PHA		;SAVE COUNTER
2071	8E64	20	0C 8E		JSR	RDBITK
2072	8E67	66	FC		ROR	CHAR
2073	8E69	68			PLA
2074	8E6A 0A				ASL	A
2075	8E6B D0 F6				BNE	KBITS	;DO 8 BITS
2076	8E6D 68				PLA		;RESTORE X
2077	8E6E AA				TAX
2078	8E6F A5 FC				LDA	CHAR
2079	8E71	2A			ROL	A
2080	8E72	4A			LSR A		;DROP PARITY
2081	8E73	60			RTS
2082	8E74
2083	8E74			; RDCHK - READ ONE BYT, INCLUDE IN CKSUM
2084	8E74
2085	8E74	20	26 8E	RDCHK	JSR RDBYTX		;FALL INTO CHKT
2086	8E77
2087	8E77			; CHKT - UPDATE CHECK SUM FROM BYTE IN A
2088	8E77			; DESTROYS		Y
2089	8E77
2090	8E77	A8		CHKT	TAY		;SAVE ACCUM
2091	8E78	18			CLC
2092	8E79	6D	36 A6		ADC	SCR6
2093	8E7C 8D 36 A6				STA	SCR6
2094	8E7F 90 03				BCC	CHKT10
2095	8E81	EE 37 A6			INC	SCR7	;BUMP HI BYTE
2096	8E84	98		CHKT10 TYA			;RESTORE A
2097	8E85	60			RTS
2098	8E86
2099	8E86	FF			.DB $FF		;NOT USED
2100	8E87				*=$8E87		;KEEP OLD ENTRY POINT

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 BCC PACKT3

Models: II

CMP

BCC

PACKT3

CMP

CMP

ADC

TXA

TAX

ADC

II specifications