Apple II specs

truncated to contain the 24 most significant mantissa bits (including sign). The absolute value of the multiplier mantissa (M2) is left in FP2. E, SIGN, and SCR are altered. The A- and X-REGs are altered and the Y-REG contains $FF upon exit.

Cautions: An exit to location $3F5 is taken if the product is less than -2^128 or greater than +2^128-1.

Notes: FMUL will run faster if the absolute value of the multiplier mantissa contains fewer '1's than the absolute value of the multiplicand mantissa.

Example: Prior to calling FMUL, FP1 contains +12 and FP2 contains -5.

_____

FP1:

$83

$60

(+12)

_____

FP2:

$82

$B0

(- 5)

_____

X2 M2

After calling FMUL, FP1 contains -60 and FP2 contains +5.

	_____		_____		_____		_____

FP1:	$85	$88			0		0	(-60)
_____		_____		_____		_____
	X1		M1
	_____		_____		_____		_____

FP2:	$82	$50			0		0	(+ 5)
_____		_____		_____		_____
	X2		M2

FDIV subroutine (addr $F4B2)

Purpose: To perform division of floating point numbers.

Entry: The normalized dividend is in FP2 and the normalized divisor is in FP1.

Exit: The signed normalized floating point quotient is left in FP1. The mantissa (M1) is truncated to 24 bits. The 3-bit M1 extension (E) contains the absolute value of the divisor mantissa. MD2, SIGN, and SCR are

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

Models: II

II specifications