Power Controller

The PowerBook G4 computer can operate from a 15 volt power outlet on an airline, but for safety reasons, the computer will not allow battery charging. In order for the computer to detect the connection to airline power, the airline power cable should have a sense resistor of 24.3K ohms connected between the power plug's shell and ground. The PowerBook G4 computer has a new variable speed fan control circuit and a new thermal circuit that will force the unit to sleep if the processor temperature...

PowerPC G Microprocessor

The PowerPC G4 microprocessor used in the PowerBook G4 computer has many powerful features, including an efficient pipelined system bus called MaxBus. 32-bit PowerPC implementation Apple Computer, Inc. November 2002 Velocity Engine AltiVec technology 128-bit-wide vector execution unit dual 32 KB instruction and data caches an on-chip level 2 L2 cache consisting of 256 KB with a clock speed ratio of 1 1 high bandwidth MaxBus also compatible with 60x bus fully symmetric multiprocessing capability...

Fire Wire Controller

The Uni-N IC includes an IEEE 1394a FireWire controller with a maximum data rate of 400 Mbits 50 MB per second. The Uni-N IC provides DMA direct memory access support for the FireWire interface. The controller in the Uni-N IC implements the FireWire link layer. A physical layer IC, called a PHY, implements the electrical signaling protocol of the FireWire interface and provides the electrical signals to the port. For more information, see FireWire Connector page 35 .

Fire Wire Connector

The FireWire connector has six contacts, as shown in Figure 3-2. The connector pin assignments are shown in Table 3-2. Table 3-2 Pin assignments on the FireWire connector Ground return for power and inner cable shield Twisted-pair B, differential signals Twisted-pair B, differential signals Twisted-pair A, differential signals Twisted-pair A, differential signals When the computer is on or the power adapter is connected, the power pin provides a maximum voltage of 17 V no load and up to 6 W...

Using the Fn

Pressing the Fn key affects three sets of keys the function keys F1-F12, the embedded numeric keypad, and certain modifier keys. It toggles the function keys between their control-button operation and their F1-F12 functions, as shown in Table 3-9 page 56 and Figure 3-6 page 53 . In Mac OS 9, the user selects the default modes of operation of those keys as described in the section The Function-Keys Checkbox page 55 . It selects the embedded numeric keypad on the right portion of the alphanumeric...

Open Firmware

The software architecture implemented on current Macintosh computers follows the standard defined by the Open Firmware IEEE 1274-1994 specification. Three Technical Notes provide an introduction to Open Firmware on the Macintosh platform. They are TN1061 Open Firmware, Part I, available at TN1062 Open Firmware, Part II, available at TN1044 Open Firmware, Part III, available at Other Technical Notes provide additional information about Open Firmware on the Macintosh. TN2000 PCI Expansion ROMs...

Velocity Engine Alti Vec

Velocity Engine is Apple's name for the AltiVec vector processor in the PowerPC G4 microprocessor. Apple provides support for developers who are starting to use the Velocity Engine in their applications. Documentation, development tools, and sample code are available on the World Wide Web, at vDSP.html Apple Computer, Inc. November 2002 AltiVec Technology Programming Environments Manual AltiVec PEM is a reference guide for programmers. It contains a description for each instruction and...

Memory Controller and Bus Bridge

The Uni-N memory controller and bus bridge IC provides cost and performance benefits by combining several functions into a single IC. It contains the memory controller, the PCI bus bridge, the Ethernet and FireWire interfaces, and the AGP interface. Each of the separate communication channels in the Uni-N IC can operate at its full capacity without degrading the performance of the other channels. In addition to the four buses listed in Table 2-1, the Uni-N IC also has separate interfaces to the...

Appearance

Figure 1-1 is a front view of the PowerBook G4 computer. Figure 1-2 is a back view showing the I O ports. Figure 1-1 Front view of the computer Figure 1-1 Front view of the computer Apple Computer, Inc. November 2002 Figure 1-2 Back view showing I O ports Figure 1-2 Back view showing I O ports

Ethernet Port

The PowerBook G4 computer has a built-in Ethernet port that supports 10Base-T, 100Base-T, and 1000Base-T transfer rates. In operation, the actual speed of the link is auto-negotiated between the computer's PHY device and the network bridge or router to which it is connected. The connector for the Ethernet port is an RJ-45 connector on the back of the computer. Table 3-3 shows the signals and pin assignments for 10Base-T and 100Base-T operation. Table 3-4 shows the signals and pin assignments...

Keyboard Illustrations

Apple Powerbook Kebord Layout

Figure 3-5 shows the actual appearance of the keyboard. Figure 3-6 shows the alternate modes of operation of the function and control keys. Figure 3-7 shows the embedded numeric keypad. Figure 3-6 and Figure 3-7 include duplicate versions of some keys in order to show their alternate modes of operation. In some cases, the alternate key captions shown in the figures do not appear on the keyboard. For the actual appearance of the keyboard, refer to Figure 3-5. Figure 3-6 Alternate operations of...