Technical information

CHAPTER 3
Devices and Ports
48 Infrared Communication Link
Infrared Communication Link 3
The computer has a directed infrared (IR) communication link connected
internally to serial port B. When the computer is placed within range of another
device with an IR interface, it can send and receive serial data using one of
several communications protocols. The other device may be another
IR-equipped PowerBook, a desktop computer with an IR communications link,
or some other device that complies with the Infrared Data Association (IrDA)
standard. The minimum range of the IR link is approximately 2 inches, and the
maximum range is 34 inches for IrDA compliant devices and 6 feet for
PowerBooks.
The IR link in the Macintosh PowerBook G3 Series computers supports IrDA at
up to 4.0 Mbps. The IrDA modulation method complies with the IrDA physical
layer standard, which can be found at ftp://irda.org.
Flat Panel Display 3
The PowerBook G3 Series 1999 computer has a built-in color flat panel display
that is 14.1 inches across, measured diagonally. The display contains 1024 by
768 pixels and can show up to millions of colors. The display is backlit by a cold
cathode fluorescent lamp (CCFL). The display uses TFT (thin-film transistor)
technology for high contrast and fast response.
The graphics controller IC includes a scaling function that expands smaller
images to fill the screen. By means of the scaling function, the computer can
show images at either 640 by 480 or 800 by 600 resolution using the full screen.
Scaling up of smaller displays also reduces the pixel resolution of the display, as
shown in Table 3-9.
The scaling function is available only when the internal flat panel is the only
active display. When the internal display and an external monitor are both
operating and mirror mode is selected, both displays show full-sized images
only when the display resolution for the external monitor is set to the standard
resolution: 1024 by 768. Both displays can operate with other resolution
settings, but in mirror mode, one of them will have a display that is smaller
than the full screen and has a black border around it. With the resolution for the