Slave Status Blocks - ProSoft Technology MVI56-PNPM User Manual

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5.2.7 Slave Status Blocks

Slave status blocks send status information of each slave device on a master
port. Slaves attached to the master port can have one of the following states:
0 The slave is inactive and not defined in the command list for the master port.
1 The slave is actively being polled or controlled by the master port and
communications is successful.
2 The master port has failed to communicate with the slave device. Communications
with the slave is suspended for a user defined period based on the scanning of the
command list.
Slaves are defined to the system when the module opens a channel to a slave.
Each slave defined will be set to a state of one in this initial step. If the master
port fails to communicate with a slave device (retry count expired on a
command), the master will set the state of the slave to a value of 2 in the status
table. This suspends communication with the slave device for a user specified
scan count (ErrorDelayCntr value in the PNPPort object for each port). Each
time a command in the list is scanned that has the address of a suspended
slave, the delay counter value will be decremented. When the value reaches
zero, the slave state will be set to one. This will enable polling of the slave.
Block ID
3000
3100
The format of these blocks is as shown in the following table:
Offset
0
1 to 247
The module will recognize the request by receiving the special write block code
and respond with a read block with the following format:
Offset
0
1
2 to 129
130 to 248
249
ProSoft Technology, Inc.
January 2, 2008
Phantom Network Protocol Master Communication Module
Description
Request for first 32 slave status values for Port 1
Request for first 32 slave status values for Port 2
Description
3000 or 3100
Spare
Description
Reserved
Write Block ID
Slave Poll Status Data
Spare
3000 or 3100
MVI56-PNPM ♦ ControlLogix Platform
Length
1
246
Length
1
1
128
119
1
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