Rockwell Automation 57C445 AutoMax PC Link Interface Module - Manual (Page 43)

D3Ć3
Link module will then clear the lower four bits of the RECONFIG byte.
The host may use this to indicate that it is all right to write the new
configuration. The host may also place any initial data in the
DATA_TABLE at this point. When the configuration information is
complete, and all data in the DATA_TABLE is in the desired state, the
host then clears the remaining bits of the RECONFIG byte. The PC
Link module will then go on line" and begin passive monitoring if
enabled. This process is demonstrated in the sample program
RIOCNF.C.
The VIR_ENA table is used to enable virtual drops. It consists of 7
bytes (2001H-2007H) corresponding to the 7 possible remote I/O
drops. Drop 1 is enabled by the host writing a nonĆzero value in
0x2001; drop 2 is enabled with 0x2002, etc. These locations are
checked only during a reĆconfigure. Any changes after a reĆconfigure
is complete will have no effect. If a virtual drop is enabled, the host
must also fill in appropriate configuration information in the
configuration buffer table (CNF_BUF) which corresponds to the drop
being enabled. See section 3.2 of this appendix for more information
on drop configuration.
The PASV_ENA table is used to enable passive monitoring of real
drops, and consists of 7 bytes (2008H-200FH) corresponding to the
7 possible remote I/O drops. Drop 1 monitoring is enabled by the
host writing a nonĆzero value in 2009H; drop 2 is enabled with
200AH, etc. These locations are checked only during a reĆconfigure.
Any changes after a reĆconfigure is complete will have no effect. If
passive monitoring for a given drop is enabled, the host must also fill
in appropriate configuration information in the CNF_BUF which
corresponds to the drop to be monitored. See section 3.2 of this
appendix for more information on drop configuration.
The VIR_ACT table is filled in by the RERIO software and is used to
indicate to the host that a given virtual drop is actively communicating
with the Master. A nonĆzero value in 2011H indicates that drop 1 is
virtual and active; 2012H indicates the status of drop 2, and so on.
ACT_MAS is a oneĆbyte flag is set by the RERIO software to indicate
to the host that the PC Link module is receiving from the Remote I/O
network Master. This will be nonĆzero as long as the PC Link module
is receiving from the Master, except during a reĆconfigure, when all
status indicators are cleared.
The DROP_ACT table is filled in by the RERIO software and is used
to indicate to the host that a given drop (virtual or real) is actively
communicating with the Master. A nonĆzero value in 2021H indicates
that drop 1 is active; 2022H indicates the status of drop 2, and so on.
Note that an active status for a real drop indicates only that the
Master is successfully communicating with the drop. It does not
necessarily indicate that the given drop is operating correctly.
The CNF_BUF table starts at 2100H and consists of 7 buffers, each
256 bytes long. The buffer at 2100H holds configuration information
for drop 1, 2200H contains information for drop 2, and so on. The
configuration information can be filled in by the host for virtual and
passively monitored drops. The PC Link module will receive
configuration information over the network for a given real drop any
time that drop goes inactive and becomes active again. The RERIO
software will automatically update the CNF_BUF for the given drop,
but will not reĆconfigure. If the Master goes inactive and then
becomes active again, the PC Link module will update the
configuration for all the real drops on the network. The PC Link
module will overwrite any configuration information in the