Bufadh, Ddrdig, LOADT2 | Apple II manual

1729	8C78		BUFADH	=$FF
1730	8C78		;TAPDEL =$A630		;HI SPEED TAPE DELAY
1731	8C78		;KMBDRY =$A631		;KIM READ BDRY
1732	8C78		;HSBDRY =$A632		;HS READ BDRY
1733	8C78		;TAPET1 =$A635		;HS FIRST 1/2 BIT
1734	8C78		;TAPET2 =$A63C		;HS SECOND 1/2 BIT
1735	8C78		;SCR6	=$A636	;SCR6
1736	8C78		;SCR7	=$8637	;SCR7
1737	8C78		;SCR8	=$A638	;SCR8
1738	8C78		;SCR9	=$A639	;SCR9
1739	8C78
1740	A64A			*=$A64A
1741	A64A		EAL	.BLOCK 1	;P3L - END ADDR +1 (LO)
1742	A64B		EAH	.BLOCK 1	;P3H -	(HI)
1743	A64C		SAL	.BLOCK 1	;P2L - START ADDR (LO)
1744	A64D		SAH	.BLOCK 1	;P2H -	(HI)
1745	A64E		ID	.BLOCK 1	;P1L -	ID
1746	A64F
1747	A64F		EOT	= $04
1748	A64F		SYN	= $16
1749	A64F		TPBIT	=%1000	;BIT 3 IS ENABLE/DISABLE TO DECODER
1750	A64F		FRAME	=$FF	;ERROR MSG # FOR FRAME ERROR
1751	A64F		CHECK	=$CC	;ERROR # FOR CHECKSUM ERROR
1752	A64F		LSTCHR	=$2F	;LAST CHAR NOT '/'
1753	A64F		NONHEX =$FF		;NON HEX CHAR IN KIM REC
1754	A64F
1755	A64F		;ACCESS =$8BB6		;UNRITE PROTECT SYSTEM RAM
1756	A64F		;P2SCR	=$829C	;MOVE P2 TO $FF,$FE IN PAGE ZERO
1757	A64F		;ZERCK	=$832E	;MOVE ZERO TO CHECK SUM
1758	A64F		;CONFIG =$89A5		;CONFIGURE I/O
1759	A64F
1760	A64F		; I/O - TAPE ON/OFF IS CB2 ON VIA 1 (A000)
1761	A64F		;	TAPE IN IS PB6 ON VIA 1 (A000)
1762	A64F		;	TAPE OUT IS CODE 7 TO DISPLAY DECODER, THRU 6532,
1763	A64F		;	PB0-PB3 (A400)
1764	A64F
1765	A64F		VIAACR	=$A00B
1766	A64F		VIAPCR	=$A00C	;CONTROL CB2 TAPE ON/OFF, POR
1767	A64F		TPOUT	=$A402
1768	A64F		TAPOUT	=TPOUT
1769	A64F		DDROUT	=$A403
1770	A64F		TAPIN	=$A000
1771	A64F		DDRIN	=$A002
1772	A64F		TIMER	=$A406	;6532 TIMER READ
1773	A64F		TIM8	=$A415	;6532 TIMER SET (8US)
1774	A64F		DDRDIG	=$A401
1775	A64F		DIG	=$A400
1776	A64F
1777	A64F		; LOADT ENTER W/ID IN PARM 2, MODE IN [Y]
1778	A64F
1779	8C78			*=$8C78
1780	8C78	20 A9 8D	LOADT	JSR START	;INITIALIZE
1781	8C7B 20 52 8D		LOADT2	JSR SYNC	;GET IN SYNC
1782	8C7E 20 E1 8D		LOADT4 JSR RDCHTX
1783	8C81	C9 2A		CMP #'*'	;START OF DATA?
1784	8C83	F0 06		BEQ LOAD11
1785	8C85	C9 16		CMP #SYN	;NO - SYN?
1786	8C87	D0 F2		BNE LOADT2	;IF NOT, RESTART SYNC SEARCH
1787	8C89	F0 F3		BEQ LOADT4	;IF YES, KEEP LOOKING FOR *
1788	8C8B
1789	8C8B 06 FD		LOAD11 ASL MODE		;GET MODE IN A, CLEAR BIT6
1790	8C8D 6A			ROR A

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 Bufadh, Ddrdig, LOADT2

Models: II

BUFADH

DDRDIG

LOADT2

II specifications