Global status registers – Rockwell Automation 56AMXN/B ControlLogix AutoMax Comm Module User Manual
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AutoMax DCSNet/RE RIO Module Page
21
Publication number 56AMXN-UM002A-EN-P November 2002
Bits Description
0-6
Input mapped drop offline
8-14
Output mapped drop offline
16-22
Monitored mapped drop offline (slave only)
Table 3 Input Fault Bits
Global Status Registers
The 56AMXN diagnostic/status registers can be mapped into one of the
input tags by writing a 0 to the entry in the Configuration tag. They may
provide useful information on the operation of the network.
Registers 4-7 contain the drop status table. The module sets bits to
indicate which drops are exchanging data on the network. Register 4 bit
0 corresponds to drop 0, register 4, bit 1, corresponds to drop 1, and so
on.
The table shows how bits in the drop status table are handled by the
56AMXN in each mode.
Master Slave
Bits for slave drops are set when
the drops are online, and cleared
if they are offline.
Bit 0, corresponding to the
master, is always set.
If you disconnect the network, bit
0 remains set, all others go to 0.
If the 56AMXN is being scanned by
a master, bits for its own active
drops are set. Bits for monitored
drops are set if the drops are online,
and cleared if they are offline.
Bit 0 is set if the 56AMXN is being
scanned by a master. and is cleared
otherwise.
If you disconnect the network, all
bits go to 0.
Table 4 Drop Status Table
Register 12 contains the 56AMXN drop number. In the DCS master,
register 12 always contains 0.
Register 20 contains the 56AMXN drop depth. In the DCS master,
register 20 always contains 0.
Register 14 contains a running count of messages received.
Register 15 contains receive timeouts. This counter increments when the
module is waiting to receive but no message arrives within a timeout
period.