System for supporting DMA I/O device using PCI bus and PCI-PCI bridge comprising programmable DMA controller for request arbitration and storing data transfer information

摘要

The present invention relates to a system and method for supporting DMA I/O devices. A PCI-PCI bridge is provided to support DMA I/O devices on the PCI bus. Through the use of two signal lines and a serial link, DMA transfers may be accomplished over the PCI bus. A PCI-ISA dock bridge is also provided to allow the system to support DMA I/O devices and ISA masters (i.e., any device including DMA I/O devices on the ISA bus that generates ISA cycles) on the ISA bus.