Rockwell Automation 57C329 Remote I/O Communications, AutoMax User Manual
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2Ć9
At power up, the onĆboard processor will run diagnostics on the
microprocessor, EPROM, RAM, serial I/O, memory management unit,
and dual port memory, as well as perform systemĆlevel diagnostics.
As each test is run, a number is written out to the sevenĆsegment
display. If there is a fault during the diagnostics, the microprocessor
will halt, the watchdog will time out, and the sevenĆsegment display
will show the code of the failed diagnostic.
2.2.2
Shark Interface Module (M/N 57C554)
The Shark Interface module contains a microprocessor that interfaces
to the Shark rack's backplane through timing and buffer circuitry.
Power for the module's logic circuitry is supplied by the rack's
+5 VDC power supply. Power for the module's remote I/O network
driver is supplied by the rack's +24 VDC power supply and is
regulated at +12 VDC.
2.2.3
Remote I/O Head (M/N 57C328)
The remote I/O Head has an onĆboard power supply that provides all
voltages necessary to power the Remote I/O Head and the I/O
system. The power supply has an input voltage of 120/240 VAC.
The Remote I/O Head contains a microprocessor that connects to the
four I/O ports via the I/O interface circuitry. At power up, the Head
polls the rail subĆsystem to determine how many rails are connected
to it. Each port on the Remote I/O Head is treated like a Multibus slot
and can contain from 0Ć4 rails. Each rail is mapped to one input
register and one output register in the dual port memory of the
M/N 57C416, which allows you to mix digital inputs and outputs in
the same rail. The location of the rail's registers is fixed in the dual
port memory of M/N 57C416. See Appendix I for more information
about the Remote I/O Head's memory map.
The Remote I/O Head connects to the Remote I/O network through
one channel of a serial I/O device. The second channel of the serial
I/O device provided a monitor port for the user. A block diagram is
shown in Appendix B.
The Remote I/O Head contains a watchdog timer that is enabled
when power is turned on to the Head. The microprocessor must reset
the watchdog timer within a specified time or the microprocessor will
shut down and the RUN and CPU READY LEDs on the faceplate will
turn off.
A set of normally open contacts from the Ready Relay are provided
on the terminal strip. The contacts open whenever a problem is
detected in the onĆboard microprocessor. These contacts should be
used in an EĆstop (emergency stop) circuit to remove power from the
outputs in case of emergency. See section 3.5.5 for more information.
At power up, the onĆboard microprocessor will run diagnostics on the
microprocessor, EPROM, RAM, serial I/O, and the I/O interface, as
well as perform systemĆlevel diagnostics. As each test is run, a
number is written out to the sevenĆsegment display. If there is a fault
during the diagnostics, the microprocessor will halt, the watchdog will
time out, and the sevenĆsegment display will show the code of the
failed diagnostics.