$301, $302, and $312 respectively). The SWEET 16 subroutine of course performs the move, and is entered at Hex locations $303 to $311 (see listing Number 3).

After the move, the screen will display three lines of data, each 8 bytes long, and await entry of a new set of parameters. The three lines of data displayed on the screen are as follows:

Line 1: The first 8 bytes of data starting at $800, which is the fixed source data to be moved (in this case, the string A$).

Line 2: The first 8 bytes of data starting at the hex address entered as the destination of the move (high order byte only).

Line 3: The first 8 bytes of data starting at $0000 (the first four SWEET 16 registers).

The display of 8 bytes of data was chosen to simplify the illustration of what goes on.

Integer Basic has its own way of recording the string A$. Because the name chosen for the string "A$" is stored in 2 bytes, a total of five housekeeping bytes precede the data entered as A$, leaving only three additional bytes available for display. Integer Basic also adds a housekeeping byte at the end of a string, known as the "string terminator".

Consequently, for convenience purposes of the display, and to see the string terminator as the 8th byte, the string data entered via the keyboard should be limited to two characters, and will appear as the 6th and 7th bytes. Additionally, parameters to be entered include the number of bytes to be moved. A useful range for this demonstration would be 1-8 inclusive, but of course 1-255 will work.

Finally, the starting address of the destination of the move must be entered. Again, for simplicity, only the high-order byte is entered, and the program allows a choice between Decimal 9 and high-order byte of program pointer 1, to avoid unnecessary problems (in this demonstration enter a decimal number between 9 and 144 for a 48K APPLE).

The 8 bytes of data displayed starting at $00 will enable one to observe the condition of the SWEET 16 registers after a move has been accomplished, and thereby understand how the SWEET 16 program works.

From the article "SWEET 16: A 6502 Dream Machine", remember that SWEET 16 can establish 16 double byte registers starting at $00. This means that SWEET 16 can use the first 32 addresses on zero page.

The "events" occurring in this demonstration program can be

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Apple II manual
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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.
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