Peer Cop Communications Health Status
The table containing Peer Cop status information
fills 12 contiguous registers indexed with the numbers 0 ... 11 in
an MBP_MSTR operation. Each individual bit in the
table words is used to present one aspect of communications health
for a specific node on the Modbus Plus network. To program an MBP_MSTR
block to get Peer Cop health status, use function code 9.
Network Implementation
A Peer Cop communications health status operation can be performed only on Modbus Plus networks.
Relation Bit Network Node
The bits of the words 0 to 3 represent the health at the global communications input of nodes 1 to 64. The bits of words 4 ... 7 represent the health of the output of a specific node.
The bits in words 8 to 11 represent the health of the input of a specific node.
Status type |
Word index |
Relation bit network node |
|---|---|---|
Global receive |
0 |
|
1 |
|
|
2 |
|
|
3 |
|
|
Send direct |
4 |
|
5 |
|
|
6 |
|
|
7 |
|
|
Receive direct |
8 |
|
9 |
|
|
10 |
|
|
11 |
|
Health Bit Status
The status of the Peer Cop health bit indicates the current communications status of its assigned node. A health bit is set when the associated node accepts input for its Peer Cop data block or when it receives a signal that another node has accepted specific output data from its Peer Cop output data block. A health bit is deleted if the associated data block does not accept any communication within the configured Peer Cop health timeout period.
All health bits are deleted when interface command is executed during PLC startup. The table values become valid when the token is completely bypassed, after the command has been carried out. The health bit of a specific node is always 0 when the assigned Peer Cop entry is 0.