PC/PCI Header (J6D1)

PC/PCI Header (J6D1) The PC/PCI header, J6D1, enables a PCI device to generate a legacy interrupt request (IRQ) to the IRQ controller (PIIX4E). This allows for legacy support of programs that expect IRQs 5, 7 or 9. The header also includes a REQ#GNT# signal pair that allows direct memory access (DMA) cycles to occur on the PCI bus.