RF08 disk controller
The RF08 disk controller was a disk device controller for RS08 disk drives on the OMNIBUS of PDP-8s and PDP-12s. One RF08 could handle up to four RS08 drives. It used the three cycle data break form of DMA to transfer data directly to main memory. Data transfers can range from 1 to 4,096 words, and 'spiral' read and write operations are supported.