bdm@ciprico.mn.org (Bill D. Moren) (09/18/87)
RIMFIRE 3500 VMEbus SCSI HOST BUS ADAPTER WITH FLOPPY PORT The Rimfire 3500 VMEbus SCSI bus adapter from Ciprico Inc. was designed to be the highest performance and most cost effective adapter available. It accomplishes this goal with a software interface derived from Ciprico's high performance VMEbus disk controllers and an extremely fast though elegantly simple hardware architecture. * Command Queuing * 30 Mbyte/sec. VMEbus Software Interface Transfer Rate * Pass Through SCSI * 4.0 Mbyte/sec. Synchronous, Commands 1.5 Mbyte/sec. Asynchronous SCSI Transfer Rates * Complete UNIX Device Drivers Available * Single-ended or Differential SCSI Bus Transceivers * Floppy Port Providing complete control over SCSI bus operations, a software interface using pass through commands allows the system to select which commands are sent to the peripheral controllers. Rimfire 3500 parameter blocks have a SCSI command descriptor block embedded in them. The board will issue the command descriptor block directly to the SCSI bus upon reading it from system memory. This allows the use of any mandatory, optional, and vendor unique SCSI commands as well as commands defined in the Common Command Set (CCS) specification. A large circular command queue, designed for system software, links the operating system to the Rimfire 3500 adapter. The queue, with a command capacity exceeding practical limits, receives requests from the operating system driver as soon as they are ready, with no timing restrictions. With access to all pending SCSI requests, the Rimfire 3500 board can take advantage of the disconnect/reconnect capability of the SCSI bus and issue overlapped commands for different devices. With a transfer rate capability of 30 Megabytes/second, Ciprico's proprietary Short Burst FIFO gate array and VMEbus interface combination increase bus efficiency. By moving data across the bus at a rate limited by the capability of most memory boards, the Rimfire 3500 adapter uses only a small fraction of the available bus bandwidth for data transfers. Optional support for up to 4 single, dual, or quad density floppy drives provides users with an economical method of providing floppy capability in their system. By buffering all floppy data in on-board local memory, SCSI performance is never degraded during floppy activity. Supporting IBM PC XT/AT compatible drives, floppies continue to prove valuable as a method of loading software patches and updates, running diagnostics, transporting files, and even as a modest backup alternative. A 4.0 Megabyte/second synchronous SCSI bus transfer rate capability, as well as a 1.5 Megabyte/second asynchronous rate capability, eliminates the possibility of any transfer rate bottlenecks. With data rates of SCSI bus peripherals continually increasing, the Rimfire 3500 adapter has the ability to meet future needs. With single-ended or differential bus transceivers, system to peripheral interconnection choices are made by the systems designer, not the board supplier. Even if today's needs are met with everything in a single enclosure, where single-ended transceivers fit the need, tomorrows expansion may mean an external cabinet. The Rimfire 3500 adapter was designed with this in mind, providing differential capability as a standard option. The Rimfire 3500 SCSI host bus adapter is available today with a list price of $1395 for a single-ended transceiver and floppy version of the board. For more information on the Rimfire 3500 adapter, or any of Ciprico's VMEbus, Multibus I, or Multibus II compatible mass storage controllers, contact Bill Moren at Ciprico: Ciprico Inc. 2955 Xenium Lane Plymouth, MN 55441 (612) 559-2034 or at: rs !&L%!&L%!