Header Type 0

General

Figure 22-1 on page 771 illustrates the format of a function's Header region (for functions other than PCI-to-PCI bridges and CardBus bridges). The registers marked in black are always mandatory. Note that although many of the configuration registers in the figure are not marked mandatory, a register may be mandatory for a particular type of device. The subsequent sections define each register and any circumstances wherein it may be mandatory.

Figure 22-1. Header Type 0

As noted earlier, this format is defined as Header Type 0. The registers within the Header are used to identify the device, to control its functionality and ...

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