82371AB Description
As a PCI-to-ISA bridge, PIIX4 integrates many mon I/O functions found in ISA-based PC systems two 82C37 DMA Controllers, two 82C59 Interrupt Controllers, an 82C54 Timer/Counter, and a Real Time Clock. In addition to patible transfers, each DMA channel supports Type F transfers. PIIX4 also contains full support for both PC/PCI and Distributed DMA protocols implementing PCI-based DMA.