Window DAC Base Register (W_DAC)
Address: 87.6000.07C0
The Window DAC Base register provides the <7:0> address bits for comparison against PCI address <39:32> during a DAC cycle. PCI address <63:40> must be zero for a PCI window hit. The DAC BASE register is used in conjunction with the W_BASE register.

The DAC BASE register is only applicable to window 3 and only if enabled by the DAC enable bit in W_BASE[3]

The Target Window is a "Hit" when the following is satisfied:

  • The incoming PCI address bits <31:20> matches one of the four Window Base Registers (WBRs); the W_MASK register determines which bits are involved in the comparison.
  • PCI address <63:40> is zero
  • PCI address<39:32> match the DAC_BASE<7:0>
Reserved<31:8>
RO		 N/A
DAC_BASE <7:0><7:0>
RW		 DAC BASE specifies bits <39:32> of the PCI base address used to determine a hit in the target window for the DAC cycle.