C H A P T E R 7

Routing and Communications

Transports can dynamically switch from one type of status slip to another without closing the status slip, and can easily update the contents of the status slip as well (for example, updating a progress indicator).

All transports that use the standard status slips have a similar user interface and match the use of other status slips throughout the system. For general information on status slips, see “Status Slips” on page 2-20.

A status slip’s Close box allows a user to hide the slip without halting the action that the slip is monitoring. If a user taps a status slip’s Close box, the transport closes the slip and registers the action with the system’s Notify service. The Notify service displays the flashing notify button at the top of the screen and adds the action to the Notify picker as described in “Notify Button and Picker” on page 8-2. The action continues in the background, and the user can perform another task. The user can also redisplay a status slip by choosing the corresponding action from the Notify picker. If a transport completes an action while its status slip is not displayed, the transport must unregister the action so the Notify service will remove it from the Notify picker.

A status slip’s Stop button allows a user to halt the action that the slip is monitoring, as described in the next section.

Stopping a Send or Receive in Progress

A transport should stop an ongoing send or receive operation as soon as possible under two conditions. One is when a user taps the Stop button in the transport’s status slip. The second is when the system notifies the transport that it wants to turn off power.

If the system is about to turn power off while a transport is engaged (not idle), the transport should handle the situation gracefully. Generally this means displaying a confirmation alert asking for the user to confirm that it is OK to break the connection. After the user consents, the system waits for the transport to become idle before turning off the power.

Stopping a Send or Receive in Progress

7-31

Page 236 Page 238
Page 237
Image 237
Apple 2 manual Stopping a Send or Receive in Progress
Page 236 Page 238

2 specifications

The Apple II is a defining product in the history of personal computing, first introduced in 1977 by Apple Computer, Inc. Designed by Steve Wozniak, the Apple II was one of the first highly successful mass-produced microcomputer products and played a significant role in bringing personal computers into homes and schools.

One of the Apple II's standout features was its color graphics capability. It was one of the first personal computers to provide color output, thanks to its built-in video interface. The initial model supported a resolution of 280x192 pixels with a palette of 6 colors, which allowed for vibrant visuals that set it apart from contemporaries like the monochrome Altair 8800.

The Apple II was notable for its open architecture. This design allowed users to expand the computer's capabilities easily through a series of expansion slots. Users could add floppy disk drives, additional memory, and various peripheral devices, making the system highly adaptable to individual needs. This encouraged a thriving ecosystem of third-party hardware and software, which contributed to its popularity.

Another significant feature was its use of the 6502 microprocessor. This 8-bit CPU was not only affordable but also powerful for its time, allowing the Apple II to run various applications efficiently. Along with a built-in keyboard and an innovative plastic case that housed its components, the design was user-friendly and appealing.

The Apple II also introduced the concept of “bootable software” through the use of floppy disks. The disk operating system (DOS) allowed users to store and run multiple programs without having to reload software manually, providing a level of convenience that had not been widely available before. Key software like VisiCalc, the first spreadsheet program, helped boost sales, showcasing the Apple II's utility in business and education environments.

The computer was also well-known for its early adoption of BASIC programming language. Apple provided an operating system that supported Applesoft BASIC, which enabled users, including students, to write their programs, further fostering a community of developers.

In summary, the Apple II's color graphics, open architecture, powerful 6502 processor, innovative use of floppy disks, and support for BASIC programming made it a revolutionary product in its time. Its legacy laid the groundwork for future personal computers and established Apple as a leader in the burgeoning tech industry. The Apple II remains an iconic symbol of the early personal computing era, reflecting a generation's transition into a digitally connected world.
Top Page Image Contents