INY NO, INC Index X-COORD | Apple II instruction

F820: C8	119		INY		; NO, INC INDEX (X-COORD)
F821: 20 0E F8	120		JSR	PLOT1	;PLOT NEXT SQUARE
F824: 90 F6	121		BCC	HLINE1	;ALWAYS TAKEN
F826: 69 01	122	VLINEZ	ADC	#$01	;NEXT Y-COORD
F828: 48	123	VLINE	PHA		; SAVE ON STACK
F829: 20 00 F8	124		JSR	PLOT	; PLOT SQUARE
F82C: 68	125		PLA
F82D: C5 2D	126		CMP	V2	;DONE?
F82F: 90 F5	127		BCC	VLINEZ	; NO, LOOP
F831: 60	128	RTS1	RTS
F832: A0 2F	129	CLRSCR	LDY	#$2F	;MAX Y, FULL SCRN CLR
F834: D0 02	130		BNE	CLRSC2	;ALWAYS TAKEN
F836: A0 27	131	CLRTOP	LDY	#$27	;MAX Y, TOP SCREEN CLR
F838: 84 2D	132	CLRSC2	STY	V2	;STORE AS BOTTOM COORD
	133				; FOR VLINE CALLS
F83A: A0 27	134		LDY	#$27	;RIGHTMOST X-COORD (COLUMN)
F83C: A9 00	135	CLRSC3	LDA	#$00	;TOP COORD FOR VLINE CALLS
F83E: 85 30	136		STA	COLOR	;CLEAR COLOR (BLACK)
F840: 20 28 F8	137		JSR	VLINE	;DRAW VLINE
F843: 88	138		DEY		;NEXT LEFTMOST X-COORD
F844: 10 F6	139		BPL	CLRSC3	;LOOP UNTIL DONE
F846: 60	140		RTS
F847: 48	141	GBASCALC PHA			;FOR INPUT 000DEFGH
F848: 4A	142		LSR
F849: 29 03	143		AND	#$03
F84B: 09 04	144		ORA	#$04	;	GENERATE GBASH=000001FG
F84D: 85 27	145		STA	GBASH
F84F: 68	146		PLA		;	AND GBASL=HDEDE000
F850: 29 18	147		AND	#$18
F852: 90 02	148		BCC	GBCALC
F854: 69 7F	149		ADC	#$7F
F856: 85 26	150	GBCALC	STA	GBASL
F858: 0A	151		ASL
F859: 0A	152		ASL
F85A: 05 26	153		ORA	GBASL
F85C: 85 26	154		STA	GBASL
F85E: 60	155		RTS
F85F: A5 30	156	NXTCOL	LDA	COLOR	;INCREMENT COLOR BY 3
F861: 18	157		CLC
F862: 69 03	158		ADC	#$03
F864: 29 0F	159	SETCOL	AND	#$0F	;SETS COLOR=17*A MOD 16
F866: 85 30	160		STA	COLOR
F868: 0A	161		ASL		;BOTH HALF BYTES OF COLOR EQUAL
F869: 0A	162		ASL
F86A: 0A	163		ASL
F86B: 0A	164		ASL
F86C: 05 30	165		ORA	COLOR
F86E: 85 30	166		STA	COLOR
F870: 60	167		RTS
F871: 4A	168	SCRN	LSR		;READ SCREEN Y-COORD/2
F872: 08	169		PHP		;SAVE LSB (CARRY)
F873: 20 47 F8	170		JSR	GBASCALC	;CALC BASE ADDRESS
F876: B1 26	171		LDA	(GBASL),Y	;GET BYTE
F878: 28	172		PLP		;RESTORE LSB FROM CARRY
F879: 90 04	173	SCRN2	BCC	RTMSKZ	;IF EVEN, USE LO H
F87B: 4A	174		LSR
F87C: 4A	175		LSR
F87D: 4A	176		LSR		;SHIFT HIGH HALF BYTE DOWN
F87E: 4A	177		LSR
F87F: 29 0F	178	RTMSKZ	AND	#$0F	;MASK 4-BITS
F881: 60	179		RTS
F882: A6 3A	180	INSDS1	LDX	PCL	;PRINT PCL,H

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 INY NO, INC Index X-COORD

Models: II

INY

; NO, INC INDEX (X-COORD)

II specifications