ProSoft Technology MVI56-DFCMR - Manual (Page 77)

Reference MVI56-DFCMR ♦ ControlLogix Platform
DF1 Interface Module with Reduced Data Block
ProSoft Technology, Inc. Page 77 of 113
October 20, 2008
Register Range File Start File End Content Size
7600 to 7700 N45:0 N45:199 Misc. Status Data 200
7800 to 7999 N46:0 N46:199 Command Control 200
8000 to 9999 N47:0 N56:199 Reserved 2000
All the data in the module is available to a remote host. This permits the host
device to remotely configure the module and view the status data.
5.2.3 Master Driver
In Master Mode, the MVI56-DFCMR module is responsible for issuing read or
write commands to slave devices on the DF1 network. These commands are
user configured in the module via the Master Command List received from the
ControlLogix processor or issued directly from the ControlLogix processor (event
command control). Command status is returned to the processor for each
individual command in the command list status block. The location of this status
block in the module's internal database is user defined. The following flow chart
and associated table describe the flow of data into and out of the module.
Step Description
1 The Master driver obtains configuration data from the ControlLogix processor. The
configuration data obtained includes the number of commands and the Master
Command List. These values are used by the Master driver to determine the type of
commands to be issued to the other nodes on the DF1 network.
2 After configuration, the Master driver begins transmitting read and/or write commands to
the other nodes on the network. If writing data to another node, the data for the write
command is obtained from the module's internal database to build the command.
3 Presuming successful processing by the node specified in the command, a response
message is received into the Master driver for processing.