Runway bus

From Wikipedia, the free encyclopedia

In computing, the Runway bus is a front side bus used by several generations of PA-RISC processor family from the PA7200, through the PA8000, PA8200, PA8500, PA8600 and PA8700. It is a 64-bit bus running at 125MHz with transfer rates up to 960 MB/s, or 2 GB/s when working on DDR mode.

Most machines use the Runway bus to connect the CPUs directly to the IOMMU (Astro, U2/Uturn or Java) and memory. However, the N class and L3000 servers use an interface chip called Dew to bridge the Runway bus to the Merced bus that connects to the IOMMU and memory.

PA8800 and PA8900 use the same bus as the Itanium 2 processor.