Contemporary Control Systems PCI20U Adapters - Manual

PCI20U
Universal Voltage PCI Bus ARCNET® Network Interface Modules
INSTALLATION GUIDE
INTRODUCTION
The PCI20U series of ARCNET network interface modules (NIMs) links
PCI and PCI-X bus compatible computers with the ARCNET local area
network (LAN). Since most PC motherboards have migrated from the +5 V
PCI Bus to the +3.3V PCI Bus, a universal voltage PCI NIM is required. In
addition, the PCI20U series supports the PCI Add-in card specification.
Both standard height and low-profile brackets are provided. The PCI Bus
allows for jumperless configuration and Plug and Play operation. The module
operates with either an NDIS driver or a null stack driver in a Windows
®
environment. DOS drivers will operate when used with our enabler software.
Since the PCI20U is a universal voltage PCI card it can be used in either a
PCI-X slot or a conventional PCI slot. PCI-X is an enhancement to the
original PCI Local Bus Specification enabling devices to operate at speeds up
to 133 MHz. If a PCI20U is installed into a bus capable of PCI-X operation,
the clock remains at the 33 MHz frequency and other devices on that bus are
restricted to using conventional PCI protocol.
The PCI20U incorporates the COM20022 ARCNET controller chip with
enhanced features over the earlier generation ARCNET chips. New features
include command chaining, sequential access to internal RAM, duplicate node
ID detection and variable data rates up to 10 Mbps. Bus contention problems
are minimized since the module’s interrupt level and I/O base address are
assigned through Plug and Play. There is no requirement for wait-state
arbitration.
The PCI20U exploits the new features of the COM20022. This includes
10 Mbps communications utilizing the various EIA-485 transceiver options.
Each PCI20U module has two LEDs on the board for monitoring network
operation and bus access to the module. It is equipped with an 8 position,
general purpose DIP switch typically used to assign the ARCNET node
address. Ultimately, the node address is
configured via software so the DIP
switch can also indicate user-defined
functions such as data rate, cable
interface, or master/slave status of the
system.