GE VMIVME-5576 Fiber-Optic Reflective Memory with Interrupts

VMIVME-5576

Fiber-Optic Reflective Memory with Interrupts

High-speed, easy-to-use fiber-optic network (170 Mbaud serially)

Data written to memory in one node is also written to memory in all nodes on

the network

Up to 2.000 m between nodes and up to 256 nodes

Data transferred at 6.2 Mbyte/s without redundant transfer

Data transferred at 3.2 Mbyte/s with redundant transfer

Any node on the network can generate an interrupt in any other node on the

network or in all network nodes with a single command

Error detection

Redundant transmission mode for suppressing errors

No processor overhead

No processor involvement in the operation of the network

Up to 1 Mbyte of Reflective Memory

A24:A32:D32:D16:D8 memory access

Single 6U VMEbus board

INTRODUCTION

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VMIVME-5576 is a

high-performance, multidrop VME-to-VME network. Data is

transferred by writing to on-board global RAM. The data is

automatically sent to the location in memory on all Reflective

Memory boards on the network.

PRODUCT OVERVIEW

The Reflective Memory

concept  provides a very fast and efficient way of sharing data

across distributed computer systems.

VMIC’s VMIVME-5576 Reflective Memory interface

allows data to be shared between up to 256 independent

systems (nodes) at rates up to 6.2 Mbyte/s. Each Reflective

Memory board may be configured with 256 Kbyte to 1 Mbyte

of on-board SRAM. The local SRAM provides fast Read

access times to stored data. Writes are stored in local SRAM

and broadcast over a high-speed fiber-optic data path to other

Reflective Memory nodes. The transfer of data between nodes

is software transparent, so no I/O overhead is required.

Transmit and Receive FIFOs buffer data during peak data

rates to optimize CPU and bus performance to maintain high

data throughput.

The Reflective Memory also allows interrupts to one or

more nodes by writing to a byte register. These interrupt (three

level, user definable) signals may be used to synchronize a

system process, or used to follow any data that may have

preceded it. The interrupt always follows the data to ensure the

reception of the data before the interrupt is acknowledged.

The VMIVME-5576 requires no initialization unless

interrupts are being used. If interrupts are used, vectors and

interrupt levels must be written to on-board registers and the

interrupts armed.