Systran SCRAMNet+ VME3U, Hardware Reference Manual

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Copyright 1995, S
YS
I
RAN
Corp. 2-1 VME3U H/W REFERENCE
2. 0 INTRODUCTION
2.1 Overview
SCRAMNet
+
(Shared Common Random Access Memory Network) is a
communications network geared toward real-time applications, and based on a replicated,
shared-memory concept.
The SCRAMNet
+
VME3U host interface node board is backwards-compatible with the
original SCRAMNet Classic product with the exception of the GOLD Ring
communication protocol. The programmable byte-swapper is no longer available on
VMEbus-based products.
The SCRAMNet
+
VME3U board requires a single slot in the VMEbus chassis.
The SCRAMNet
+
VME3U board base address for Control/Status Registers (CSRs) is
switch selectable. The 128 KB on-board shared memory can be upgraded to 512 KB,
1 MB, 2 MB, 4 MB or 8 MB random access memory (RAM). Installing any memory
upgrade overrides the on-board 128 KB memory.
2.1.1 Network Features
A ring topology with 150 Mbit/s line transmission rate.
A “Data-Filter” that allows only data stored in shared memory that has changed to be
communicated to the other network nodes.
Field Upgrade Memory Options up to 8 MB of replicated, shared memory for each node
processor.
BURST Mode protocol (Error Correction Disabled) with fixed-length message packets of
82 bits.
BURST PLUS Mode communication based on variable length message packet size to a
maximum of either 256 bytes or 1024 bytes.
PLATINUM Mode protocol (Error Correction enabled) with fixed-length message
packets of 82 bits.
PLATINUM PLUS Mode communication based on variable length message packet size
to a maximum of either 256 bytes or 1024 bytes.
256 node capacity on each ring.
No operating or system software required to support network protocol.
No network-dependent application software required.