ncrsc —
NCR 53c710 SCSI I/O Processor
The ncrsc driver provides an abstraction layer between
  the SCSI hardware fitted to Motorola MVME167 and MVME177 single board
  computers (NCR73C710), and the machine independent SCSI drivers described in
  scsibus(4).
In addition to sending the required SCSI commands to target
    devices on the SCSI bus, the ncrsc driver deals with
    DMA, device interrupts, sync/async negotiation and target
    disconnects/reconnects.
The current ncrsc driver should be obsoleted and
  replaced with a machine independent version.